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The magmatic history of the Vetas-California mining district; Santander massif,eastern Cordillera, Colombia
Luis C. Mantilla Figueroa, Thomas Bissig, Víctor Valencia, Craig J.R. Hart
PII: S0895-9811(13)00043-6
DOI: 10.1016/j.jsames.2013.03.006
Reference: SAMES 1160
To appear in: Journal of South American Earth Sciences
Received Date: 1 August 2012
Accepted Date: 15 March 2013
Please cite this article as: Mantilla Figueroa, L.C., Bissig, T., Valencia, V., Hart, C.J.R., The magmatichistory of the Vetas-California mining district; Santander massif, eastern Cordillera, Colombia, Journal ofSouth American Earth Sciences (2013), doi: 10.1016/j.jsames.2013.03.006.
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Highlights
We studied the magmatic history of the Vetas-California mining district (Santander
Massif, Eastern Cordillera, Colombia
We present new U-Pb ages on intrusive Mesozoic rocks; and on detrital zircons.
The Mesozoic magmatism is related to an oblique subduction of the Panthalassa
plate beneath Pangea.
*Highlights (for review)
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THE MAGMATIC HISTORY OF THE VETAS-CALIFORNIA MINING
DISTRICT; SANTANDER MASSIF, EASTERN CORDILLERA,
COLOMBIA
Mantilla Figueroa, Luis C.1; Bissig, Thomas
2; Valencia, Víctor
3; Hart, Craig
J.R.
2
1Universidad Industrial de Santander, UIS. AA. 678. Bucaramanga (Santander, Colombia).
lcmantil@uis.edu.co 2
Mineral Deposit Research Unit (MDRU), Department of Earth and Ocean Sciences, The
University of British Columbia. Vancouver, Canada. 3School of Earth and Environmental Science, Washington State University, Pullman, WA, USA.
ABSTRACT
The Vetas-California Mining District (VCMD), located in the central part of The Santander
Massif (Colombian Eastern Cordillera), based on U-Pb dating of zircons, records the
following principal tectono-magmatic events: (1) the Grenville Orogenic event and high
grade metamorphism and migmatitization between ~1240 and 957 Ma; (2) early Ordovician
calc-alkalic magmatism, which was synchronous with the Caparonensis-Famatinian
Orogeny (~477 Ma); (3) middle to late Ordovician post collisional calc-alkalic magmatism
(~466 to 436 Ma); (4) late Triassic to early Jurassic magmatism between ~204 and 196Ma,
characterized by both S and I type calc-alkalic intrusions and; (5) a late Miocene shallowly
emplaced intermediate calc-alkaline intrusions (10.9 ± 0.2 and 8.4 ± 0.2 Ma). The presence
of even younger igneous rocks is possible, given the widespread magmatic-hydrothermal
alteration affecting all rock units in the area.
The igneous rocks from the late Triassic-early Jurassic magmatic episodes are the
volumetrically most important igneous rocks in the study area and in the Colombian Eastern
Cordillera. They can be divided into three groups based on their field relationships, whole
rock geochemistry and geochronology. These are early leucogranites herein termed
Alaskites-I (204-199 Ma), Intermediate rocks (199-198 Ma), and late leucogranites, herein
referred to as Alaskites-II (198-196 Ma). This Mesozoic magmatism is reflecting subtle
changes in the crustal stress in a setting above an oblique subduction of the Panthalassa plate
beneath Pangea.
The lower Cretaceous siliciclastic Tambor Formation has detrital zircons of the same age
populations as the metamorphic and igneous rocks present in the study area, suggesting that
the provenance is related to the erosion of these local rocks during the late Jurassic or early
Cretaceous, implying a local supply of sediments to the local depositional basins.
Keywords: Colombia, Santander Massif, Vetas-California Mining District, Magmatic
history, U-Pb Geochronology, detrital zircons.
*ManuscriptClick here to view linked References
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1. Introduction
The northeastern Cordillera of Colombia is a key area to understand the tectonic interactions
between the South American, Caribbean and North American plates, and the accreted
terranes in northwestern Colombia, in the context of multiple subduction and orogenic events
since the Proterozoic (e.g., Cediel et al. 2003; Restrepo et al., 2011). The igneous rocks that
are hosted in these tectonic blocks are records of these plate interactions, and unravelling the
timing and chemistry of these igneous bodies are crucial in interpreting the nature of such
interactions.
In this paper we provide new information on the igneous evolution of the Santander Massif
(Fig. 1), with an emphasis on the Mesozoic intrusive evolution. In particular, we evaluate the
rocks of the Vetas-California area, which is ~40 km NE of the City of Bucaramanga in the
Santander Department, Colombia. The area hosts important porphyry and epithermal style
Au and base metal mineralization, which is to a large part, hosted in the Mesozoic igneous
rocks. Therefore, an improved understanding of the intrusive history will potentially benefit
mineral exploration in the district.
We present nine new U-Pb ages on intrusive rocks and comprehensively discuss these in the
context of the previously published age constraints (Goldsmith et al., 1971; Ward et al.,
1973; Boinet et al., 1985; Dörr et al., 1995; Royero and Clavijo, 2001; Cordani et al., 2005;
Mantilla et al., 2009; Restrepo-Pace and Cediel, 2010; Leal-Mejia et al., 2011; Mantilla et al.,
2011 and 2012). In addition, we also obtained ages on detrital zircon grains extracted from
Cretaceous sandstone deposited unconformably on the pre-Cretaceous igneous and
metamorphic basement and discuss the paleogeographic implications.
2. Background and Geological Context
Basement evolution
The Colombian Andean Orogenic System is the result of Paleozoic to the middle Miocene
accretion of a series of allochthonous terranes (e.g., Restrepo et al., 2011). Cediel et al.,
(2003) subdivided the Andean region of Colombia into tectonic realms composed of the
Central Continental Subplate Realm, Maracaibo Subplate Realm, Western Tectonic Realm
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and the Guajira-Falcon Composite Terrane. The study area is located in the Maracaibo
Subplate Realm, in the sense of Cediel et al., (2003) and in the Chibcha Terrane, in the sense
of Restrepo et al., (2011; Fig.1). The Maracaibo Subplate Realm comprises the triangular
tectonic Maracaibo block between the major NNW striking Santa-Marta Bucaramanga fault
(SMBF) and the NE striking Boconó fault (Taboada et al., 1999, 2000). The study area,
located in the Vetas-California Mining District (VCMD, Fig. 1 and 2), coincides with the
southern tip of the Maracaibo Block in a cornerback position (Tschanz et al., 1974, Van der
Hilst and Mann, 1994).
The oldest rocks in the VCMD belong to the Santander Massif (Clavijo, 1994) and comprise
at least three principal metamorphic units. The main unit is the Bucaramanga Gneiss (Ward
et al., 1973; a.k.a. as Bucaramanga Complex: Clavijo, 1994), which consists of high grade
migmatitic paragneisses of early Proterozoic age (García and Ríos, 1999; Ordóñez-Cardona
et al., 2006). Peak metamorphism has been dated at 1057 ± 28 by U-Pb SHRIMP
geochronology on zircons, which emphasizes an association with the Grenvillian Orogeny
(Cordani et al. 2005). Pressures between 5.5 and 7.2 kbar and temperatures from 660 to
750°C, have been estimated for the peak metamorphism (Urueña and Zuluaga, 2011). The
Bucaramanga Gneiss is overlain by the Silgará Formation; composed mainly of late
Proterozoic to early Paleozoic ortho-amphibolites, schists, phyllites, metasiltstones,
meta-sandstone, meta-greywackes and minor amounts of marble; and is also part of the
metamorphic basement of the Santander Massif (Ward et al., 1973, Schaefer et al., 1998;
García and Ríos, 1999; Ríos et al., 2003). This unit is not outcropping in the VCMD but
present in the surrounding areas (Ward et al., 1973). Upper amphibolite facies metamorphic
conditions (Schäfer et al., 1998) and early-middle Ordovician peak metamorphic ages; likely
related to the Caledonian or more specifically to the Caparonensis-Famantinian orogeny;
have also been reported (Forero, 1990, Rios et al., 2003; Ordóñez-Cardona et al., 2006,
Clavijo et al., 2008; Restrepo-Pace and Cediel, 2010).
Meta-diorites, dated at 477 Ma by zircon U-Pb LA-ICPMS, have been documented for the
Angostura project area within the VCMD (Mantilla et al. 2012) and represent the youngest
rocks affected by the high grade metamorphism. These rocks are related to an episode of
mantle-derived magmatism in a subduction setting, possibly emplaced during the
Caparonensis-Famantinian orogeny (Mantilla et al., 2012).
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Late Paleozoic to Recent evolution
All metamorphic rocks in the study area are older than 471 Ma (Restrepo-Pace and Cediel,
2010). Non or weakly metamorphosed igneous rocks coincident with or post-dating the
Caledonian orogeny, have been reported in the eastern Cordillera (Goldsmith et al. 1971,
Ward et al., 1973), and are recorded in detrital zircons (see below). However, igneous or
sedimentary rocks of ages between 470 and 210 Ma have not been mapped in the VCMD.
Magmatism here resumed in the late Triassic and early Jurassic. Previous workers
(Goldsmith et al. 1971, Ward et al., 1973) documented tonalites and granodiorites at Páramo
Rico in the southeastern part of the study area, whereas leucogranites and quartz monzonites
are recognized in the central part of the VCMD (Fig. 2). These felsic rocks have generally
been considered to be younger than the more mafic rock varieties. Limited K-Ar
geochronology on muscovite places the leucogranites at 195±7 Ma (Goldsmith et al., 1971;
Ward et al., 1973), somewhat younger than the age reported for intermediate composition
rocks from Páramo Rico which was dated by conventional U-Pb on zircons at 205 to 210 Ma
(Dörr et al. 1995). The latter are considered I-type granitoids by Dörr et al. (1995) as they
contain hornblende and titanite (cf., Chappel and White, 1974).
Sedimentary rocks unconformably cover the igneous and metamorphic rocks in the western
part of the study area. Directly overlying the basement are the sandstones and conglomeratic
sandstones of the lower Cretaceous Tambor Formation (Mendoza and Jaramillo, 1979). The
siliciclastic rocks are interpreted to have been deposited in an alluvial environment in local
depocenters such as half-grabens (Ward et al. 1973, Mendoza and Jaramillo, 1979; Royero
and Clavijo, 2001; Sarmiento, 2001), while most of the Santander Massif remained emergent
throughout the Mesozoic (Etayo-Serna et al., 1983; Fabre, 1985,1987; Sarmiento, 1989;
Cooper et al., 1995, Sarmiento, 2001).
Magmatism younger than mid Jurassic is scarce. Some published Cretaceous K-Ar ages for
granitic rocks are probably unreliable as these rocks have likely been affected by partial
resetting or alteration (e.g, Hargraves et al., 1984; Dörr et al 1995) and these rocks are
considered part of the late Triassic to early Jurassic intrusive episodes. However, narrow
dikes and, locally, up to 1 km diameter intrusions of porphyritic granodiorites, have been
observed and are post-Cretaceous in age because they intrude the Cretaceous sedimentary
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rocks (Ward et al., 1973; Polania, 1980, 1983; Galvis, 1998, Cooperación Técnica
Colombo-Alemana, 1998, Felder et al. 2005). Recently reported geochronological data
(Mantilla et al., 2009 and 2011; Leal-Mejia et al. 2011), indicate that these lithologies overall
span the interval between 10.9 ± 0.2 and 8.4 ± 0.2 Ma. Magmatic hydrothermal alteration and
mineralization overprints these late Miocene igneous rocks indicating that gold
mineralization is, contrary to previously published Re/Os age constraints (Mathur et al.
2003), not Paleocene but 10.9 Ma or less in age. This Miocene magmatism in the VCMD,
temporally coincides with reactivation and sinistral transpressional movement of the
Bucaramanga-Santa Marta fault (BSMF), likely related to the accretion of the Chocó block,
and rapid uplift of this part of the Eastern Cordillera (Dengo and Covey, 1993; Kellogg and
Vega, 1995; Taboada et al., 1999; Villamil, 1999; Taboada et al. 2000; Pindell and Kennan,
2001, Villagómez et al. 2011).
Uplift and exhumation history of the Eastern Cordillera
A positive tendency (i.e., tendency of the earth surface to stay emergent) of the Santander
Massif (SM), during the continental and marine Mesozoic sedimentation in Colombia, was
proposed by Juliver (1963b), on the basis of thinner continental siliciclastic Upper Jurassic
Girón Formation toward the massif and the presence of lower Cretaceous evaporitic rocks
surrounding it. This positive tendency continued during the Early Cretaceous as documented
by Etayo-Serna et al. (1983) and Fabre (1985). There is no evidence that the SM was
emergent during the late Cretaceous (at least since the Turonian-Coniacian), as is supported
by the preservation of the marine sedimentary record on some areas of the SM for this time
period. However, the positive tendency of the SM resumed in the Tertiary (Juliver, 1963b).
On the basis of zircon and apatite fission track ages, uplift and exhumation initiated in the
southern corner of the triangular Maracaibo block, where the study area is located, in the late
Cretaceous to Paleogene, and a major and final uplift pulse occurred in the Plio-Pleistocene
(Shagan et al., 1984; Horton et al. 2010; Nie et al. 2010; Villagómez et al. 2011).
Paleobotanical data indicate that rapid uplift of the Colombian Eastern Cordillera took place
between 5 and 2 Ma (Gregory-Wodzicki, 2000). The collision of the Panama-Chocó island
arc with the northwestern margin of the South American plate between 12 and 6 Ma (Dengo
and Covey, 1993; Kellogg and Vega, 1995) has been related to the deformation in the Eastern
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Cordillera. There is a general consensus that uplift of the Western and Central Cordilleras
took place mostly in the late Cretaceous–Paleocene, while the uplift of the Eastern Cordillera
mostly occurred in the Pliocene–Pleistocene (Gregory-Wodzicki, 2000; Villagómez et al.
2011). At 4 Ma the Eastern Cordillera probably had no more than 40% of its current elevation
(Gregory-Wodzicki, 2000).
3. Analytical techniques
U-Pb (LA) ICP-MS in Zircons
Heavy mineral concentrates of the <350 µm fraction were separated using traditional
techniques at ZirChron LLC at Washington State University. Zircons from the non-magnetic
fraction were mounted in epoxy and slightly ground and polished to expose the surface and
keep as much material as possible for laser ablation analyses.
LA-ICP-MS U-Pb analyses were conducted at Washington State University after CL
imaging using a New Wave Nd:YAG UV 213-nm laser coupled to a ThermoFinnigan
Element 2 single collector, double-focusing, magnetic sector ICP-MS. Operating procedures
and parameters are a modification of Chang et al. (2006). Laser spot size and repetition rate
were 30 nm and 10 Hz, respectively. He and Ar carrier gases delivered the sample aerosol to
the plasma. Each analysis consisted of a short blank analysis followed by 250 sweeps
through masses 204, 206, 207, 208, 232, 235, and 238, taking approximately 30 seconds.
Time-independent fractionation was corrected by normalizing U-Pb and Pb/Pb ratios of the
unknowns to the zircon standards (Chang et al., 2006). For this study we used two zircon
standards: Peixe, with an age of 564 Ma (Dickinson and Gehrels, 2003), and FC-1, with an
age of 1099 Ma (Paces and Miller, 1993). Uranium-lead ages were calculated using Isoplot
(Ludwig, 2003) and includes the systematic and analytic errors (2).
U-Pb TIMS in zircons
One sample was dated by Thermal Ionization Mass Spectrometry (TIMS) procedures
following a procedure modified from Mundil et al., (2004), Mattinson, (2005) and Scoates
and Friedman, (2008). This analysis has been performed at the Pacific Center for Isotope and
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Geochemical Research (PCIGR), University of British Columbia, Canada. After rock
samples have undergone standard mineral separation procedure, zircon grains were
handpicked in alcohol, and then annealed in quartz glass crucibles at 900° C for 60 hours.
Grains were chemically abraded (leached) in ultrapure HF and HNO3 at 175°C for 12 hours.
Single grains were then dissolved in HF and nitric acids in a 10:1 ratio at 240°C for 40 hours.
Each sample was spiked with a 233‐ 235U‐205Pb tracer. The resulting solutions were dried
at 130°C and the fluoride precipitate was dissolved in 6N HCl in high pressure Parr devices
for 12 hours at 210°C. The resulting HCl solutions were mixed with 2 μL of 0.5 NH3PO4 and
dried. Samples were finally loaded onto degassed, zone‐refined Re filaments in 2 μL of
silicic acid emitter (Gerstenberger and Haase, 1997). Isotopic ratios were measured using a
modified single collector VG‐54R or VG‐354S (the latter with Sector 54 electronics) thermal
ionization mass spectrometer (TIMS) equipped with an analogue Daly detector. Analytical
blanks are 0.2 pg for U and for Pb in the range of 1‐10 pg. U fractionation was determined
directly on individual runs using the 233‐235U tracer, and Pb isotopic ratios were corrected
for fractionation of 0.23%/amu, based on replicate analyses for the NBS‐982 Pb reference
material and the values recommended by Thirwhall (2000). Data reduction employed the
Microsoft Excel based program of Schmitz and Schoene (2007). Standard concordia
diagrams were constructed and regression intercepts weighted averages calculated with
Isoplot (Ludwig, 2003). All errors are quoted at the 2σ or 95% level of confidence.
U-Pb (LA) ICP-MS in detrital zircons
Detrital zircons from sample TB-CV-008 (Fig. 2), collected at latitude 7°20'58,0"and
longitude 72°56'51,1" (or local coordinates X=1.304.631; Y=1.124.764; Z= ~2020 mosl;
Bogotá as origin of the reference system; Plane Gauss Krüger projected coordinates), were
analyzed at PCIGR at the University of British Columbia, Vancouver, Canada; using a laser
ablation (LA) ICP-MS technique, as described by Tafti et al. (2009). Instrumentation
employed for LA-ICP-MS dating of zircons at the PCIGR, comprises a New Wave UP-213
laser ablation system and a ThermoFinnigan Element2 single collector, double-focusing,
magnetic sector ICP-MS. Zircons were randomly separated from a concentrate comprising
the entire recovered populations and then were mounted in an epoxy puck along with several
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grains of the Plešovice zircon standard (Sláma et al., 2007), together with zircon standard
FC-1, and brought to a very high polish. The surface of the mount was washed for 10 minutes
with dilute nitric acid and rinsed in ultraclean water prior to analysis. Portions of each grain,
free of alteration, inclusions, or possible inherited cores, were selected for analysis. Line
scans rather than spot analyses were employed in order to minimize elemental fractionation
during the analyses. A 25 micrometer spot size was used for all analyses. Backgrounds were
measured with the laser shutter closed for ten seconds, followed by data collection with the
laser firing for approximately 35 seconds. The time-integrated signals were analysed using
GLITTER software (Van Achterberghet et al. 2001; Griffin et al. 2008), which automatically
subtracts background measurements, propagates all analytical errors, and calculates isotopic
ratios and ages. Corrections for mass and elemental fractionation were made by bracketing
analyses of unknown grains with replicate analyses of the Plešovice zircon standard. Final
interpretation and plotting of the analytical results was done using ISOPLOT software of
Ludwig (2003). Data are listed at the 2 sigma confidence level and plotted on standard
concordia diagrams. The best estimate for the age of these detrital zircons is given by the
207Pb/
206Pb age if 1500 Ma and older or the
206Pb/
238Pb age if younger than 1500 Ma; these
age picks are used to construct a probability density plot. All data on this latter plot are less
than ± 5% discordant. Only one analyzed grain was more than 5% discordant and not used.
Whole rock geochemistry
Sixteen rocks samples of Mesozoic rocks were analyzed by whole rock geochemistry at the
‗Acme Analytical Laboratories Ltd‘, Vancouver, British Columbia, Canada. Out of these a
subset of 11 samples containing rocks unaffected or only minimally affected by
hydrothermal alteration were selected for further data analysis (Appendix B). The samples
were analyzed by the analytical package 4A-4B by ICP-emission mass spectrometry
following a lithium metaborate/tetraborate fusion and dilute nitric acid digestion. A separate
sample split was digested in Aqua Regia and analyzed by ICP mass spectrometry for
precious and base metals. The analytical data are presented in digital appendix B. Two
additional analyses of Tonalite (sample 7-1-1-89) and granodiorite (10-1-5-89) were
compiled from Dörr et al., (1995).
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4. Results
4.1. Field relationships of igneous rocks
The oldest Phanerozoic igneous rocks recognized in the study area include meta-gabbros to
meta-granodiorites that were affected by regional deformation but locally cut an older
foliation of the Bucaramanga Gneiss (Mantilla et al. 2012). These rocks have generally been
assigned a pre-Devonian age (Boinet et al., 1985) and were emplaced synchronously with the
early Ordovician Caparonensis–Famatinian orogenic event (Restrepo-Pace and Cediel,
2010).
The most prominent and volumetrically most important intrusive units observed in the study
area are multiphase plutons and dikes ranging in composition from tonalite and diorite to
granodiorite, quartz-monzonite and granite (Fig. 2). These are all unaffected by regional
metamorphism. These intrusive rocks can be classified into three groups on the basis of the
observed cross-cutting relationships and geochronology.
The oldest is an igneous muscovite-biotite leucogranite, herein referred to as Alaskite-I,
following earlier nomenclature (Evans, 1977). Leucogranites of the Alaskite-I unit are
usually medium-grained and form dikes and intrusive bodies of modest size. The dikes range
in average thickness from about 30 cm to about 20 m and their strike is dominantly WNW,
dipping 80° SW (Fig. 3A), but shallowly-dipping dikes have been recognized locally at Veta
de Barro Angostura Project (ENE, dipping 30° NW). Larger igneous bodies assigned to this
rock group can reach up to 2.5 km2 in map view (Fig. 2).
The intermediate group of rocks are tonalite, diorite and granodiorite and form large plutons
up to 9 km2 (Fig. 2). Intermediate intrusive rocks locally contain centimetre-scale mafic
subrounded and rounded blocks that may be enclaves, restites or xenoliths (Fig. 3B). The
intermediate group of rocks cut Alaskite-I, as observed at about 1.2 km to the east of the town
of California. At La Chorrera (Fig. 2), Alaskite-I forms centimetre-scale xenoliths and
meter-scale rafts within the more mafic lithologies (Fig. 3C). The latter locally displays a
weak tectonic foliation (Fig. 3D) and in other places a magmatic flow alignment of mafic
minerals.
Fine-grained, equigranular igneous muscovite-bearing quartz-monzogranites that are
petrographically very similar to those described above, intrude and contain xenoliths of the
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intrusions of intermediate composition (Fig. 3E), indicating that there are at least two
separate episodes of muscovite-bearing granitoid emplacement separated by the intrusion of
intermediate magmas. These younger granites are herein referred to as Alaskite-II. These
rocks occur as dykes and igneous bodies (Fig. 3F) similar to those of Alaskite-I and the two
alaskite units can only be distinguished with confidence in outcrop if direct cross-cutting
relationships with the intermediate rocks are exposed.
4.2. U-Pb Geochronology
Nine samples from late Triassic to early Jurassic igneous rocks were collected from Alaskites
(I and II) and intermediate igneous rocks (Fig. 2) and dated, following the methodologies
described above (see Table 1; Fig. 4-7; Appendix A).
Alaskites-I
Four Alaskite-I samples were collected from dikes and stocks from El Cuatro (along the La
Baja Creek, Sample ALR035); Violetal Hill (in the central part of the study area; sample
GI-47-M1) and along the California-Vetas road (samples GE-20-M1 and TQB-002; Fig. 2,
Table 1).
Sample ALR035 is an illite/sericite-altered fine-grained equigranular granite dike containing
primary muscovite. Samples GI-47-M1, GE-20-M1 and TQB-002 are from alkali-feldspar
granite but are affected by moderate quartz-sericite hydrothermal alteration and cut by
quartz-pyrite veins. Sample GE-20-M1, is an alkali-feldspar granite with biotite and
muscovite from a fractured dike of about 20 meters thickness with a west north westerly
strike and 80° dip to the Southwest. This dyke cuts the Bucaramanga Gneiss and has not been
affected by macroscopically recognizable hydrothermal alteration. The other two samples
(GI-47-M1 and TQB-002) were collected from stocks of alkali-feldspar granites (Fig. 2).
Sample TQB-002 has been affected by macroscopically recognizable hydrothermal
alteration.
Zircons from all samples are euhedral and display concentric oscillatory zoning, indicating a
magmatic origin.
Sample ALR035, the only one dated by the U-Pb TIMS method on zircon, presents
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significant inherited zircons. Three of five analyzed zircons are discordant. The two youngest
grains define a 206
Pb/207
Pb age of 210.6±3.5 Ma. A lower Concordia intercept at ~201Ma
defines a minimum age (Fig. 4).
Samples GE-20-M1, GI-47-M1 and TQB-002 were all dated by zircon
U-Pb-LA-MCICP-MS (Fig. 5A, B, C; Appendix A). The U-Pb juvenile ages for these
samples are: 204.3+2.7/-3.3 Ma for sample GE-20-M1; 202.2+5.3/-3.0 Ma for sample
GI-47-M1 and; 199.1+2.5/-2.6 Ma for sample TQB-002. All of these samples contain
significant inherited zircon populations (Fig. 8). Out of 103 analyzed points, 20 are
considered inherited or mixed ages because they yield apparent ages ranging from
Proterozoic to Carboniferous, whereas the remaining 83 point analyses yield ages between
245.7 and 187.2 (Appendix A).
Intermediate rocks
Three samples of intermediate rocks were dated. One was taken just outside the town of
California on the road to Bucaramanga (sample TQB-005, Fig. 6B), and two additional
samples were collected along the California-Vetas road (TPD-71 and TQB-003, Table 1;
Fig. 6A, 6C; Appendix A). These samples are unaltered diorite-granodiorite rocks with
quartz, plagioclase, orthoclase, biotite and hornblende and no muscovite (the total estimated
content of mafic mineral is ≥ 30%).
Zircons are euhedral and display concentric oscillatory zoning, indicating a magmatic origin.
The obtained U-Pb juvenile ages for these samples are: 199.2+2.8/-2.7 Ma for sample
TPD-71; 199.0+2.5/-2.6 Ma for sample TQB-005 and; 198.4+2.4/-2.4 Ma for sample
TQB-003 (Table 1). All of these samples also contain significant inherited zircon
populations (Fig. 8). Out of 118 analyzed points, 14 are considered inherited (or mixed ages)
with ages ranging from Proterozoic to Carboniferous, whereas the remaining 104 point
analyses yield ages between 253.0 and 119.7 Ma (Appendix A).
Alaskites-II
Two samples from Alaskite-II rocks were dated in this study (samples TQB-004, TQB-001
Table 1, Fig. 3E and 3F). These rocks are quartz-plagioclase-K-feldspar granite with biotite
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and muscovite, very similar to Alaskite I but distinguished from those in that they contain
xenoliths of intermediate rocks. These samples were collected along the California-Vetas
road (Fig. 2).
Zircons are euhedral and display concentric oscillatory zoning, indicating again their
magmatic origin. The U-Pb juvenile ages obtained from these samples are 198.7+2.6/-2.9Ma
for sample TQB-004 and 196.7+2.9/-2.8 Ma for sample TQB-001 (Table 1; Fig. 7A, 7B).
Both of these samples also contain inherited zircon populations, but significantly less
Grenvillian and older zircons, comparing with the Alaskite-I and Intermediate rocks (Fig. 8).
Out of 84 analyzed points, 16 are considered inherited (or mixed ages) with ages ranging
from Proterozoic to Permian, whereas the remaining 68 point analyses yield ages between
245.6 and 130.7 Ma (Appendix A).
4.3. Detrital zircons U-Pb Geochronology
A sample of quartz-rich sandstone of lower Cretaceous Tambor Formation was taken from
west of the town of California. This sedimentary unit unconformably overlies the
Bucaramanga Gneiss and the igneous Mesozoic rocks. Sixty-three detrital zircons grains
were analyzed (sample TB-CV-008, Fig. 2), out of these only a single analysis was
discordant and is not further considered. The following age populations are recognized (Fig.
9A-D; Appendix A): 1) nine analysis define a early to middle Proterozoic age group from
1810 to 1338 Ma; 2) twenty six points yielded middle Proterozoic ages of 1298 to 939 Ma; 3)
one zircon was dated at 756.6 Ma; 4) six zircons have ages between 494 and 473 Ma; 5)
twelve analyses fall between 466 and 436 Ma and; 6) nine analyses represent ages from 209
to 195 Ma (Appendix A). The most important groups of ages are represented in the
probabilistic age peaks shown in Fig. 9B.
4.4. Geochemistry
Given that rocks in the Vetas-California district are commonly affected by hydrothermal
alteration due to proximal hydrothermal mineral deposits, the geochemical data were
evaluated using a number of standard alteration evaluation diagrams (e.g. Davies and
Whitehead, 2006; not shown here) to check for the degree of mobility of the large ion
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lithophile elements (LILE) which include mainly K, Na and Ca. The geochemical data and
petrographic observations in 5 out of 16 analyzed samples indicate hydrothermal alteration,
mainly the destruction of plagioclase and replacement by muscovite ± quartz assemblages,
silicification and the addition of iron from pyrite. Elevated P2O5 and TiO2 in one specimen
was also an indication that these elements may not have been immobile during alteration in
some samples. The altered samples are not further discussed below. Widely used
classification plots readily identify the Mesozoic igneous rocks of the Santander Massif as
subalkaline (Fig. 10A) and as high-K calc-alkaline rocks. The intermediate late Triassic to
early Jurassic rocks have dioritic compositions with SiO2 contents of 54.9 to 60.4 wt.%. The
Alaskites all plot as alkali granites and granites but no distinction between Alaskite I and II
can be made. The immobile trace element diagrams Zr/TiO2 vs Nb/Y and SiO2 vs Zr/TiO2
(Winchester and Floyd, 1977; Fig. 10C and 10D) also identify the intermediate rocks as
subalkaline diorite whereas the alaskites plot in the monzonite/quartz-monzonite fields.
In the Aluminum saturation index diagram by Maniar and Piccoli (1989), all Alaskite rocks (I
and II) plot in the peraluminous field, whereas the five intermediate rock samples (Appendix
B) are metaluminous (Fig. 10B).
Chondrite normalized patterns for rare earth elements (REE) for the Alaskite I and II units
(Fig. 10E), display relatively flat HREE patterns although some scatter in the degree of
HREE enrichment relative to chondrite is evident, especially in Alaskite II samples.
However all Alaskites show a pronounced negative Eu anomaly which is indicative for
plagioclase fractionation. The late Triassic to early Jurassic diorites are more enriched in
heavy REE relative to chondrite and their negative Eu anomaly is less pronounced when
compared to the Alaskites (Fig. 10E). The Ta vs. Yb diagram (Pearce et al. 1984) reveals that
all rocks plot as a tight cluster within the volcanic arc field, although the granites have
slightly higher Ta contents and straddle the border to the syn-collisional granite field (Fig.
10F).
5. Discussion
Juvenile U-Pb zircons ages from late Triassic-early Jurassic Igneous rocks
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The U-Pb LA-MCICP-MS zircon geochronology shows that Triassic to Jurassic magmatism
occurred over a relatively restricted time interval between ~210 and 196 Ma. The three
intrusive units Alaskite-I, Intermediate and Alaskite II can be distinguished
geochronologically, although some age overlap exists between them. Besides the significant
inherited age component, crystallization ages of Alaskite I are between 204.3+2.7/-3.3 Ma to
199.1+2.5/-2.6 Ma. The 2103.5 Ma 206
Pb/207
Pb TIMS age of sample ALR035 is possibly
an inhereted component but the minimum age estimate of 201 Ma for this sample is
consistent with the age range for alaskite-I established by LA-MCICP-MS geochronology.
The intermediate igneous rocks are slightly younger and have U-Pb zircon ages from
199.2+2.8/-2.7 Ma to 198.4+2.4/-2.4 Ma although the errors overlap with the Alaskite I and
II units. The latter has ages of 198.7+2.6/-2.9Ma and 196.7+2.9/-2.8Ma. The late
Triassic-early Jurassic magmatism reported here for the VCMD is the volumetrically most
important igneous episode recognized in the Colombian eastern Cordillera. Rocks of this age
are present across the entire Santander Massif (SM) as batholiths, stocks and dykes (Ward et
al., 1973; Clavijo, 1994; Fig. 1). Limited age equivalent stocks, dikes, lava flows and
volcanoclastic materials have also been reported west of the BSMF in the Magdalena River
Valley domain.
The late Triassic to early Jurassic magmatism in the SM includes both, peraluminous rocks
with a large crustal component and metaluminous intermediate-mantle derived intrusions in
temporal and spatial proximity.
Detrital and Inhered U-Pb zircons ages
The detrital zircons of the Tambor Formation record all previous known igneous and major
metamorphic events in the Santander massif previously documented by mapping and igneous
geochronology (Goldsmith et al., 1971; Ward et al., 1973; Dörr et al., 1995; Cordani et al.,
2005; Mantilla et al., 2012). These include Proterozoic zircons, most importantly dated at
~1300 to 940 Ma, but also some older grains between ~1810 and ~1340 Ma. The younger of
these two episodes can readily be related to the Grenvillian orogeny and includes the age of
the peak metamorphism of the Bucaramanga Gneiss (Cordani et al., 2005), whereas the
oldest group of ages are probably inherited from the protolith of the Bucaramanga Gneiss
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which, on the basis of Sm-Nd model ages, has been estimated at 1760 to 1710 Ma
(Ordoñez-Cardona et al., 2006). An alternate explanation for this Paleoproterozoic age
population would be that these zircons may have been derived from upper Paleozoic
sedimentary rocks, shedding off the Amazonian craton, after the Chibcha Terrane accretion
(Restrepo et al., 2011). However, given the absence of documented upper Paleozoic
sedimentary rocks in the study area, we interpret the oldest zircon population as derived from
the Bucaramanga Gneiss. The single 756.6 Ma zircon recorded in the Tambor Formation
cannot be related to a specific mapped geologic unit in the district but is here interpreted as
derived from the post Grenvillian Silgará formation. An early Ordovician age population of
494 to 472 Ma can readily be matched to the metamorphosed meta-diorites documented by
Restrepo-Pace and Cediel (2010) and Mantilla et al. (2012). Magmatism of late Caledonian
age (Restrepo-Pace and Cediel, 2010) can be matched to detrital zircon ages of 466 to 436
Ma, whereas the detrital age population of 209 to 195 Ma matches the late Triassic to early
Jurassic magmatic episode documented above well. Overall, the detrital zircon data indicate
that all igneous and metamorphic units presently exposed in the study area were already
subject to erosion in the lower Cretaceous, as previously suggested by Juliver, (1963a,b);
Fabre and Delaloye, 1983), and Sarmiento, (2001).
Inherited zircon grains from Mesozoic igneous rocks record, in broad terms, the same
pre-Mesozoic age populations as the detrital zircons of the Tambor Formation. The oldest
zircon ages from 1740 to 1334 Ma (8 analyses) recorded by studied Mesozoic igneous rocks,
are interpreted as inherited from the host Bucaramanga Gneiss and likely correspond to its
protolith age; as was interpreted in previous studies (Cordani et al., 2005; Ordóñez-Cardona
et al., 2006; Mantilla et al., 2012). Inherited zircon ages of 1240 to 958 Ma (5 analyses) are
also interpreted as derived from the host Bucaramanga Gneiss, and likely corresponding to
the Grenvillian metamorphic peak (Cordani et al., 2005; Mantilla et al., 2012). The older ages
within the age group from 920 to 500 Ma (8 analyses), may correspond to late metamorphic
events of the Grenvillian orogeny as documented by Cordani et al., (2005) and Restrepo-Pace
(1995), the latter using 40
Ar/39
Ar hornblende from amphibolite. The younger ages in the
range, may also be related to post Grenvillian metamorphic events, mixing ages or
alternatively (?) may be related to undated diabase (dolerite) dikes outcropping in the SM,
which have been interpreted to have intruded during the opening of the western Iapetus
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Ocean (Pisarevsky et al., 2008).
The age groups from 475 to 302 Ma (27 analyses) may be interpreted as inhered from the
early Ordovician meta-igneous rocks (ages >470 Ma) present in the study area (Mantilla et
al., 2012) and also from igneous rocks without regional metamorphism (470-370 Ma in age)
that were emplaced in different areas of the SM, as has been documented by Restrepo-Pace
and Cediel, (2010). The latter magmatic event has not been documented but may be
represented by scarce granitic pegmatite dykes observed in the study area. Younger ages
(<370 Ma), likely represent mixed ages, but in cannot be excluded that they represent
presently unknown rocks units.
The two Permian ages of 287 and 270 Ma reported for zircons in Alaskite-II rocks, are also
interpreted as mixed ages although they may also represent inhered zircons from unknown
Permian igneous rocks, which, however, have not been reported from the Santander Massif.
Paleotectonic Implications
The existence of a proto-Andean Orogenic system during the Grenvillian (1.0 Ga) and
Famatinian (0.47 Ga), have been reported for the SM (Restrepo-Pace et al.1997; Cordani et
al., 2005; Chew et al., 2007; Restrepo-Pace and Cediel, 2010). The granitoids emplaced
during the Caparonensis-Famatinian Orogeny (Restrepo-Pace and Cediel, 2010), are related
to mantle-derived magmas emplaced in a supra-subduction paleotectonic setting, are affected
by a regional metamorphic foliation and have been dated at 477±2 Ma in the study area
(Mantilla et al., 2012). The Mesozoic leucogranites of the Alaskite I and Alaskite II units are
geochemically similar to each other despite the fact that they can be distinguished by
cross-cutting relationships and are separated in time by the intrusion of intermediate rocks.
The Alaskites are peraluminous as they contain magmatic muscovite and their subduction
signature in the trace elements is subdued. The Alaskite I unit is interpreted to have been
emplaced in a relatively continent-ward position during late Triassic eastward subduction of
the Panthalassa oceanic plate (or Paleo-Pacific; Farallon Plate) beneath Pangea (Fig. 11). A
slight tectonic change, potentially related to the initial rifting of the central Atlantic Ocean
may have provided a locally more extensional setting for the emplacement of the
intermediate rocks. The latter are not peraluminous and exhibit no geochemical evidence for
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major crustal assimilation although some inherited zircons indicate that limited crustal
contamination must have occurred. The early Jurassic intermediate rocks are followed by
peraluminous granitic rocks (Alaskite II) with similar characteristics to those which pre-date
the intermediate rocks indicating a return to a similar tectonic configuration as prior to the
emplacement of the intermediate rocks. Magmatism probably ceased in the region after ~190
Ma, potentially due to initiation of rifting related to the opening of the Proto-Caribbean
Ocean and westward retreat of the subduction zone, as also suggested by by Bayona et al.,
(2006).
The reported geochemical data from late Triassic-early Jurassic Magmatic rocks support
continental margin magmatism, but the sedimentary succession from this time interval
indicates deposition in an extensional setting (Bayona et al., 2006). Restrepo et al., (2011),
supported by zircon U-Pb SHRIMP ages, obtained from Nechí Gneiss (Tahami Terrane, core
of the Colombian Central Cordillera), pointed out that the metamorphism of this terrane has
likely taken place in an Andean-type orogenesis (about 226 Ma age in the late Triassic), on
the western side of Pangea (not by the collision of Laurentia and Gondwana to form Pangea).
The late Triassic-early Jurassic magmatism in the SM is consistent with an oblique supra
subduction setting, as proposed by Aspden et al., (1987) and documented by Bayona et al.,
(2006) on the basis of paleomagnetic data. The tectonic changes required for the shift from
peraluminous to metaluminous and then again to peraluminous magmatism, reported also for
other areas affected by oblique subduction (e.g., Collins and Hobbs, 2001) is here interpreted
as a function of crustal residency time during ongoing subduction. In this scenario,
peraluminous magmatism would be the result of a more extensive interaction between the
mantle derived magma and the metasedimentary material of the crust during episodes of
contractional tectonics and crustal thickening in the upper plate. Metaluminous granite
magmatism, in contrast, may be explained by some degree of relaxation of the crust and the
subsequent ascent of mantle-derived magmas. These tectonic shifts are interpreted to have
taken place in the context of an oblique subduction of the Farallon Plate and episodic
reactivations of the Paleo-BSMF which controlled the basin evolution to the west of the
Santander Massif. Deformation during the emplacement of the metaluminous intermediate
rocks is also evidenced by the weak foliation and alignment of mafic minerals of some of
these igneous bodies.
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Magmatic activity in the Santander Massif resumed in the late Miocene (Mantilla et al., 2009,
2011). The late Miocene intrusions in the study area are narrow granodiorite porphyry dikes
and, locally, up to 1 km diameter intrusions. The generation of these melts was probably
related to the subduction of the Caribbean plate beneath this part of the northern Andes and
coincided with the collision of the Baudó-Panama terrane (Dengo and Covey, 1993; Kellogg
and Vega, 1995). The presence of even younger igneous rocks cannot be ruled out, since
magmatic-hydrothermal alteration, presumably related to intrusions at depth, post-dating the
late Miocene granodiorite porphyries has affected the area. Late Pliocene volcanism has been
documented locally at the Paipa volcano some 180 km south of VCMD in the eastern
Cordillera (Pardo et al. 2005).
6. Conclusions
The Vetas-California Mining District (VCMD) records a series of tectono-magmatic events
that took place during Proterozoic and lower Paleozoic. All pre Devonian rocks have a
regional metamorphic foliation related to the Grenvillian and Famatinian-Caparonensis
orogenies. A limited number of age determinations on inherited zircons in the late Triassic
and early Jurassic igneous rocks, and on detrital zircons from the lower Cretaceous Tambor
Formation sandstone fall in the interval between 470 and 360 Ma. These dates suggest the
presence of subordinate igneous rocks of this age range although only limited field evidence
for such rocks has been reported. Volumetrically important igneous activity took place in the
late Triassic to early Jurassic interval (204.3-196.7 Ma, Retiense-Pliensbachiense).
Leucogranite emplacement was separated by intrusion of dioritic to granodioritic rocks
reflecting subtle changes in the crustal stress in a setting above an oblique subduction of the
Panthalassa plate beneath Pangea.
The detrital zircons in the lower Cretaceous Tambor Formation, suggest that their
provenance is related to the erosion of the igneous and metamorphic rocks of the Santander
Massif recognized locally in the study area. This implies that the Santander Massif was
subject to erosion and localized deposition of the siliciclastic detritus which gave rise to the
Tambor Formation during the Berriasian-Valanginian time interval. The tectonic foliation
that locally affects the intermediate rocks from late Triassic and early Jurassic igneous rocks
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is considered the result of deformation along the proto-SMBF and other crustal scale faults
that affected the study area during the middle-late Jurassic and early Cretaceous. These
structures were re-activated later in the Neogene, leading to the most recent uplift pulses in
the northeastern Cordillera Oriental of Colombia.
Acknowledgments
We express our thanks to the Industrial University of Santander (UIS), for giving the
opportunity to pursue geological fieldwork aimed at creating new geologic knowledge on the
Colombian Geology. We would like to thank Sara Jenkins, Arne Toma, Karie Smith,
students and colleagues at the Mineral Deposit Research Unit (MDRU), at the Earth and
Ocean Sciences Department (University of British Columbia), for all their support and help.
To Hernando Mendoza and Humberto León Amaya, for their support and help during the
field works. To the community of California, Vetas and surrounding areas, for their
permanent kindness and cooperation. A special thanks to all those students from the School
of Geology at the UIS, who have done their geological fieldwork practices in the VCMD. We
gratefully acknowledge our colleagues and staff from Eco-Oro Minerals Corp., CVS
Explorations Ltd., AUX Colombia Ltda and other sponsors, for their financial contribution to
the MDRU Colombia gold and porphyry project which enabled the senior author to take a
sabbatical leave to work on the project, but also for their continuing support to the School of
Geology (UIS), especially during its geological fieldworks activities.
Figure captions
Fig. 1. Location of Vetas-California Mining District (Santander Massif, Colombian Eastern
Cordillera) with respect to Chibcha Terrane (Ch; in the sense of Restrepo et al. 2011) and the
triangular Maracaibo tectonic block (Maracaibo Subplate Realm, in the sense of Cediel et al.,
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2003), bordered by the major NNW striking Santa-Marta Bucaramanga fault and the NE
striking Boconó fault.
Fig. 2. Simplified geological map of the Vetas-California Mining District (Santander Massif,
Colombia). Geology from Ward et al., (1973), Evans (1977), Polania (1980), and this study.
Fig. 3. Outcrop photographs of Mesozoic igneous rocks of the VCMD. A. Alaskite-I dyke
cutting the Bucaramanga Gneiss (sample GE-20-M1); B. Diorite rocks containing centimetre
scale mafic subrounded and rounded mafic enclaves, C. Centimetre scale xenoliths and meter
scale rafts (composed of Alaskite-I leucogranite) within the more mafic litologies
(diorite-granodiorite rocks); D. Diorite-granodiorite rocks affected by tectonic foliation
(Sample TQB-005, close to California town); E. Leucogranite of the alaskite-II unit (dyke
covered by and Fe-Mn oxides on fracture planes) with granodiorite xenoliths; F. Road cut
along the California-Vetas road of Alaskites II leucogranite (sample TQB-004).
Fig. 4. Zircon U-Pb TIMS age from sample ALR035 (Alaskite-I from a dyke cutting La
Bodega). The two youngest grains define a 206
Pb/207
Pb age of 210.6±3.5 Ma. A lower
Concordia intercept at ~201Ma defines a minimum age for this sample.
Fig. 5. Zircon U-Pb LA-MC-ICPMS ages for Alaskite-I rocks. Concordia and distribution
diagrams, respectively, for the samples: A. GE20M1; B. GI-47-M1 and; C. TQB-002.
Fig. 6. Zircon U-Pb LA-MC-ICPMS ages from Mesozoic intermediate igneous rocks.
Concordia and distribution diagrams, respectively, for the samples: A. TPD-71; B. TQB-005;
C. TQB-003.
Fig. 7. Zircon U-Pb LA-MC-ICPMS ages from Alaskite-II rocks. Concordia and distribution
diagrams, respectively, for the samples: A. TQB-004 and B. TQB-001.
Fig. 8. Zircon U-Pb LA-MCICP-MS age distribution in Alaskites-I, Intermediate and
Alaskites-II rocks, from a total of 305 analyzed points (103 in Alaskites-I; 118 in
intermediate rocks and; 84 in Alaskites-II rocks). Inherited Grenvillian and older zircons are
significantly less abundant in Alaskite-II rocks, than in Alaskite-I and Intermediate rocks.
Fig. 9. Ages of detrital zircons from the lower Cretaceous siliciclastic Tambor formation. A.
Concordia diagram. B. Probability density plot of U-Pb ages. C. Close-up of Concordia
diagram showing early Ordovician U-Pb ages of detrital zircons derived from early
Ordovician orthogneisses. D. Late Triassic-early Jurassic U-Pb age population, derived from
detrital zircons from Mesozoic igneous rocks.
Fig. 10. Geochemical Classification diagrams for Mesozoic igneous rocks of the VCMD. A.
Irvine and Baragar (1971) discrimination diagram; B. Al/(Ca+Na+K) vs. Al/(Na+K) diagram
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from Maniar and Piccoli (1989) which readily identifies the Alaskites-I and -II as
peraluminous, whereas the intermediate rocks fall into the metaluminous field; C and D.
Zr/TiO2 vs. Nb/Y and SiO2 vs. Zr/TiO2 classification diagram after Winchester and Floyd
(1977); E. Chondrite normalized REE spider diagram. Chondrite normalization values from
Sun and McDonough (1989). F. Ta vs. Yb tectonic discrimination diagrams for granitoid
rocks, after Pearce et al., (1984). Empty squares: Intermediate igneous Mesozoic rocks;
filled squares: Mesozoic Alaskite-I rocks; Filled triangles: Mesozoic Alaskite-II rocks.
Fig. 11. A. Simplified Map of late Triassic-early Jurassic Pangea showing the approximate
location of the Colombia Territory (Modified from Lucas and Tunner, 2007). B. Simplified
geotectonic reconstruction of the study area, in which the oblique late Triassic-early Jurassic
subduction margin is shown (Modified from Bayona et al., 2006).
Table 1. Summary of zircons U-Pb geochronology results (see Appendix A).
APPENDIX A. U-Pb analytical results from igneous and detrital zircons separated and dated by
TIMS and LA-MC-ICPMS methods, from Mesozoic igneous rocks and sedimentary Lower
Cretaceous Tambor Formation. Vetas-California Mining District (VCMD). Santander Massif,
Colombia Eastern Cordillera.
APPENDIX B. Whole rock geochemical data of late Triassic-early Jurassic Igneous rocks.
Vetas-California Mining District (VCMD). Santander Massif. Colombia Eastern Cordillera.
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Santander Massif
Figure 1
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&
&
((((
((
((
((((
((
((((
((((
((
((((
((
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((((
((((
((((
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((
1125000 1130000 1135000
1300
000
1305
000
1310
000
72°52'0"W72°54'0"W72°56'0"W
7°24
'0"N
7°22
'0"N
7°20
'0"N
7°18
'0"N
Data SourcesFaults, Veins & ContactsGeologic Unit
Alaskite 1
Alaskite 2
Breccia
Bucaramanga Gneiss
Diorite to Granodiorite
Porphyry
Rosablanca Formation
Tambor Formation
TuffNormal fault
(( Thrust fault
Normal fault, inferred
& Strike-slip, dextral
Non conformity
Mineralized veins
Samples
1
2
3
This study and...1: Polania, 19802: Ward et al. 19733: Evans, 1976
California
Vetas
TQB-004TQB-003
TQB-005TQB-002 GF-47MI
TQB-001
TQB-71
GE-20-MI
ALR035
TBCV-008
U-Pb sample (igneous rock)U-Pb sample (detrital zircons)Whole rock geochemistry sample
Angostura
Violetal Mongora
Figure 2
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Fig. 3. Outcrop photographs of Mesozoic igneous rocks of the VCMD. A. Alaskite-I dyke
cutting the Bucaramanga Gneiss (sample GE-20-M1); B. Diorite rocks containing
centimetre scale mafic subrounded and rounded mafic enclaves, C. Centimetre scale
xenoliths and meter scale rafts (composed of Alaskite-I leucogranite) within the more mafic
litologies (diorite-granodiorite rocks); D. Diorite-granodiorite rocks affected by tectonic
foliation (Sample TQB-005, close to California town); E. Leucogranite of the alaskite-II
unit (dyke covered by and Fe-Mn oxides on fracture planes) with granodiorite xenoliths; F.
Road cut along the California-Vetas road of Alaskites II leucogranite (sample TQB-004).
Alaskite-I
Figure 3
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Fig. 4. Zircon U-Pb TIMS age from sample ALR035 (Alaskite-I from a dyke cutting La
Bodega). The two youngest grains define a 206
Pb/207
Pb age of 210.6±3.5 Ma. A lower
Concordia intercept at ~201Ma defines a minimum age for this sample.
Figure 4
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Fig. 5. Zircon U-Pb LA-MC-ICPMS ages for Alaskite-I rocks. Concordia and distribution
diagrams, respectively, for the samples: A. GE20M1; B. GI-47-M1 and; C. TQB-002.
A
B
C
Figure 5
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Fig. 6. Zircon U-Pb LA-MC-ICPMS ages from Mesozoic intermediate igneous rocks.
Concordia and distribution diagrams, respectively, for the samples: A. TPD-71; B. TQB-
005; C. TQB-003.
A
B
C
Figure 6
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Fig. 7. Zircon U-Pb LA-MC-ICPMS ages from Alaskite-II rocks. Concordia and
distribution diagrams, respectively, for the samples: A. TQB-004 and B. TQB-001.
A
B
Figure 7
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Fig. 8. Zircon U-Pb LA-MCICP-MS age distribution in Alaskites-I, Intermediate and
Alaskites-II rocks, from a total of 305 analyzed points (103 in Alaskites-I; 118 in
intermediate rocks and; 84 in Alaskites-II rocks). Inherited Grenvillian and older zircons
are significantly less abundant in Alaskite-II rocks, than in Alaskite-I and Intermediate
rocks.
Figure 8
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Fig. 9. Ages of detrital zircons from the lower Cretaceous siliciclastic Tambor formation.
A. Concordia diagram. B. Probability density plot of U-Pb ages. C. Close-up of Concordia
diagram showing early Ordovician U-Pb ages of detrital zircons derived from early
Ordovician orthogneisses. D. Late Triassic-early Jurassic U-Pb age population, derived
from detrital zircons from Mesozoic igneous rocks.
C D
A B
Figure 9
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Fig. 10. Geochemical Classification diagrams for Mesozoic igneous rocks of the VCMD.
A. Irvine and Baragar (1971) discrimination diagram; B. Al/(Ca+Na+K) vs. Al/(Na+K)
diagram from Maniar and Piccoli (1989) which readily identifies the Alaskites-I and -II as
peraluminous, whereas the intermediate rocks fall into the metaluminous field; C and D.
Zr/TiO2 vs. Nb/Y and SiO2 vs. Zr/TiO2 classification diagram after Winchester and Floyd
(1977); E. Chondrite normalized REE spider diagram. Chondrite normalization values from
Sun and McDonough (1989). F. Ta vs. Yb tectonic discrimination diagrams for granitoid
rocks, after Pearce et al., (1984). Empty squares: Intermediate igneous Mesozoic rocks;
filled squares: Mesozoic Alaskite-I rocks; Filled triangles: Mesozoic Alaskite-II rocks.
Figure 10
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Fig. 11. A. Simplified Map of late Triassic-early Jurassic Pangea showing the approximate
location of the Colombia Territory (Modified from Lucas and Tunner, 2007). B. Simplified
geotectonic reconstruction of the study area, in which the oblique late Triassic-early
Jurassic subduction margin is shown (Modified from Bayona et al., 2006).
FA
RA
LL
ON
PL
AT
E
MEXICAN BLOCKS
Study area
A
B
Magmatic Arc
Subduction margin
Bucaramanga Fault
Volcano-plutonic arc of the Santander Massif.Upper Triassic-Lower Jurassic
Figure 11
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Table 1. Table 1. Summary of zircons U-Pb geochronology results (see Appendix A).
Sample Coordinates Local Coordinates** Geographic
location
Rock Type Age
Latitude Longitude X Y Z (mosl)
ALR035* 7° 22' 38,7" 72° 54' 21,1 1307735 1129357 ~2496 El Cuatro
(along the ‘La
Baja’ Creek)
Alaskite-I 210.6±3.5 Ma
minimum lower
intercept age of
~201 Ma
GE-20-M1 7° 19' 00,3" 72° 53' 56,4" 1.301.027 1.130.134 ~2704 California-
Vetas road
Alaskite-I 204.3+2.7/-3.3Ma
GI-47-M1 7° 21' 21,1" 72° 54' 25,8" 1.305.351 1.129.222 ~3113 Violetal Hill Alaskite-I 202.2+5.3/-3.0Ma
TQB-002 7° 20' 55,6" 72° 56' 04,6" 1.304.559 1.126.193 ~2171 California-
Vetas road
Alaskite-I 199.1+2.5/-2.6Ma
TPD-71 7° 19' 18,6" 72° 54' 10,9" 1.301.589 1.129.689 ~2622 California-
Vetas road
Diorite-
Granodiorite 199.2+2.8/-2.7Ma
TQB-005 7° 20' 57,1" 72° 56' 49,2" 1.304.604
1.124.824
~2037 Just outside
the town of
California on
the road to
Bucaramanga
Diorite-
Granodiorite 199.0+2.5/-2.6Ma
TQB-003 7° 20' 55,6" 72° 56' 04,6" 1.304.559 1.126.193 ~2171 California-
Vetas road
Diorite-
Granodiorite 198.4+2.5/-2.6Ma
TQB-004 7° 21' 01,7" 72° 56' 16,0" 1.304.746 1.125.843 ~2182 California-
Vetas road
Alaskite-II 198.7+2.6/-2.9Ma
TQB-001 7° 19' 55,1" 72° 54' 56,8" 1.302.707 1.128.275 ~2393 California-
Vetas road
Alaskite-II 196.7+2.9/-2.8Ma
*sample dated by TIMS. All other samples were dated by LA-ICPMS.
** Bogotá as origin of the reference system; Plane Gauss Krüger projected coordinates.
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APPENDIX A.
U-Pb analytical results from igneous and detrital zircons separated and dated by TIMS and LA-MC-ICPMS methods, from Mesozoic igneous rocks and
sedimentary Lower Cretaceous Tambor Formation. Vetas-California Mining District (VCMD). Santander Massif, Colombia Eastern Cordillera.
Sample ALR035.
(Analyzed by CA-TIMS)
Wt. U Th Pb 206Pb*
mol
% Pb* Pbc 206Pb 208Pb 207Pb
207Pb
206Pb
corr. 207Pb
207Pb
206Pb
Sample mg ppm
U ppm x10-13
mol 206Pb* Pbc
(pg) 204Pb 206Pb 206Pb % err 235U % err 238U % err coef. 206Pb ± 235U ± 238U ± %
disc
(a) (b) (c) (d) (c) (e) (e) (e) (e) (f) (g) (g) (h) (g) (h) (g) (h) (i) (h) (i) (h) (i) (h)
A 0,004 1106 0,181 34,0 5,1142 99,47% 52 2,24 3485 0,058 0,050334 0,223 0,219985 0,302 0,031698 0,129 0,747 210,44 5,17 201,90 0,55 201,17 0,26 4,41
B 0,005 821 0,102 30,3 6,0173 99,68% 85 1,59 5761 0,034 0,053961 0,260 0,290734 0,331 0,039076 0,160 0,638 369,43 5,84 259,14 0,76 247,10 0,39 33,11
C 0,003 1272 0,014 37,9 5,3008 99,47% 50 2,30 3520 0,004 0,050342 0,219 0,223795 0,308 0,032242 0,146 0,757 210,82 5,08 205,06 0,57 204,56 0,29 2,97
D 0,002 442 0,287 21,0 1,7169 98,99% 28 1,44 1833 0,093 0,053899 0,394 0,346042 0,468 0,046564 0,153 0,607 366,83 8,88 301,74 1,22 293,39 0,44 20,02
E 0,004 755 0,391 40,7 6,0717 99,44% 53 2,82 3298 0,127 0,054671 0,215 0,392961 0,295 0,052130 0,126 0,759 398,81 4,82 336,53 0,84 327,59 0,40 17,86
Sample GE-20-M1
(Analyzed by (LA)ICP-MS). Points of analysis
U ppm
Th U
238U/ 206Pb
1 sigma (% error)
207Pb/ 206Pb
1 sigma (% error)
Pb206/238U (age)
1 sigma (abs err)
207Pb/206Pb (age)
1 sigma (abs err)
Best age Ma
1 sigma abs err Ma
GE20MI_44 227 0,78 28,8684 1,17% 0,0530 1,34% 219,5 2,5 330,2 30,1 219,5 2,5
GE20MI_43 2.218 0,14 25,7376 0,89% 0,0522 0,76% 245,7 2,1 292,6 17,3 245,7 2,1
GE20MI_42 462 0,92 32,5115 0,97% 0,0511 1,11% 195,3 1,9 247,2 25,4 195,3 1,9
GE20MI_41 275 0,76 30,9690 1,02% 0,0563 1,40% 204,9 2,1 465,6 30,7 204,9 2,1
GE20MI_40 462 0,92 32,5115 0,97% 0,0511 1,11% 195,3 1,9 247,2 25,4 195,3 1,9
GE20MI_39 2.812 0,20 30,9834 0,87% 0,0506 0,75% 204,8 1,7 224,4 17,2 204,8 1,7
GE20MI_38 171 1,24 3,9003 0,86% 0,0952 0,78% 1471,4 11,2 1531,5 14,5 1531,5 14,5
GE20MI_37 151 1,24 3,7640 0,89% 0,0957 0,77% 1518,8 12,0 1541,3 14,5 1541,3 14,5
GE20MI_36 1.309 0,25 31,3105 0,98% 0,0525 0,80% 202,7 2,0 307,2 18,2 202,7 2,0
GE20MI_35 345 0,14 12,3908 1,24% 0,0646 0,89% 500,3 6,0 762,1 18,6 500,3 6,0
GE20MI_34 1.059 0,22 31,0202 0,91% 0,0505 0,81% 204,5 1,8 217,4 18,7 204,5 1,8
GE20MI_33 627 0,36 27,7050 1,27% 0,0516 0,96% 228,6 2,8 268,9 21,9 228,6 2,8
GE20MI_32 1.131 0,23 28,6539 0,99% 0,0521 0,81% 221,1 2,2 288,0 18,4 221,1 2,2
GE20MI_31 348 0,91 31,0504 1,03% 0,0543 1,20% 204,3 2,1 382,8 26,8 204,3 2,1
GE20MI_30 838 0,47 31,0372 1,13% 0,0509 0,88% 204,4 2,3 235,6 20,1 204,4 2,3
GE20MI_29 1.031 0,19 31,2512 0,86% 0,0514 0,88% 203,0 1,7 260,3 20,1 203,0 1,7
GE20MI_28 1.568 0,54 14,9662 0,99% 0,0564 0,76% 417,0 4,0 466,5 16,8 417,0 4,0
GE20MI_27 730 0,91 4,0023 0,87% 0,0956 0,69% 1437,7 11,2 1540,8 13,0 1540,8 13,0
GE20MI_26 1.389 0,11 16,9530 1,11% 0,0609 0,82% 369,5 4,0 635,7 17,6 369,5 4,0
GE20MI_25 170 1,01 31,2438 1,13% 0,0584 1,66% 203,1 2,3 543,6 35,8 203,1 2,3
GE20MI_24 174 0,71 29,7955 1,12% 0,0504 1,57% 212,8 2,3 213,8 36,0 212,8 2,3
GE20MI_23 605 0,38 3,6988 1,48% 0,1142 1,05% 1542,6 20,3 1867,2 18,9 1867,2 18,9
GE20MI_22 186 0,61 30,9825 1,53% 0,0508 1,66% 204,8 3,1 233,7 37,9 204,8 3,1
GE20MI_20 472 0,89 31,7966 1,32% 0,0498 1,38% 199,6 2,6 187,9 31,9 199,6 2,6
GE20MI_19 1.454 0,19 30,2848 1,31% 0,0503 1,10% 209,4 2,7 208,1 25,4 209,4 2,7
GE20MI_18 302 1,45 14,3464 1,34% 0,0562 1,27% 434,4 5,6 461,4 27,8 434,4 5,6
GE20MI_17 1.189 0,05 31,3729 1,31% 0,0499 1,16% 202,3 2,6 188,3 26,7 202,3 2,6
GE20MI_16 92 0,55 31,0972 1,62% 0,0501 2,31% 204,0 3,2 201,5 52,7 204,0 3,2
GE20MI_15 275 1,09 30,4732 1,45% 0,0506 1,51% 208,1 3,0 223,5 34,5 208,1 3,0
GE20MI_14 791 0,36 32,0530 1,29% 0,0507 1,21% 198,0 2,5 227,6 27,6 198,0 2,5
GE20MI_13 1.122 0,28 31,3509 1,30% 0,0506 1,15% 202,4 2,6 220,4 26,5 202,4 2,6
GE20MI_12 216 0,54 30,5404 1,49% 0,0490 1,69% 207,7 3,0 145,8 39,2 207,7 3,0
GE20MI_11 301 0,16 16,6896 1,51% 0,0580 1,28% 375,1 5,5 529,9 27,9 375,1 5,5
GE20MI_10 1.365 0,06 30,9734 1,31% 0,0502 1,13% 204,8 2,6 204,4 26,0 204,8 2,6
APPENDIX A
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GE20MI_9 507 0,45 31,5584 1,33% 0,0492 1,33% 201,1 2,6 159,6 30,8 201,1 2,6
GE20MI_8 3.269 0,07 31,8438 1,27% 0,0506 1,07% 199,3 2,5 223,3 24,6 199,3 2,5
GE20MI_6 65 1,14 30,8025 1,85% 0,0511 2,43% 206,0 3,7 245,5 55,0 206,0 3,7
GE20MI_4 104 0,76 29,9328 1,69% 0,0496 2,04% 211,8 3,5 174,1 46,9 211,8 3,5
GE20MI_3 1.794 0,12 31,6835 1,27% 0,0507 1,13% 200,3 2,5 227,3 25,9 200,3 2,5
GE20MI_2 1.475 0,07 33,9445 1,75% 0,0514 1,43% 187,2 3,2 259,4 32,5 187,2 3,2
GE20MI_1 916 0,44 31,7145 1,31% 0,0504 1,18% 200,1 2,6 215,5 27,1 200,1 2,6
Sample GI-47-M1
(Analyzed by (LA)ICP-MS). Points of analysis
U ppm
Th U
238U/ 206Pb
1 sigma (% error)
207Pb/ 206Pb
1 sigma (% error)
Pb206/238U (age)
1 sigma (abs err)
207Pb/206Pb (age)
1 sigma (abs err)
Best age Ma
1 sigma abs err Ma
GI47MI_20 907 0,38 4,4569 1,07% 0,0851 0,49% 1304,9 12,7 1317,6 9,4 1317,6 9,4 GI47MI_19 431 0,68 28,4115 1,19% 0,0503 1,08% 223,0 2,6 208,4 24,9 223,0 2,6 GI47MI_18 658 0,55 18,0462 1,12% 0,0571 0,65% 347,7 3,8 495,8 14,2 347,7 3,8 GI47MI_17 655 0,51 30,3425 1,08% 0,0522 0,76% 209,0 2,2 293,5 17,2 209,0 2,2 GI47MI_16 1.226 0,28 29,7991 1,07% 0,0515 0,67% 212,8 2,2 262,1 15,4 212,8 2,2 GI47MI_15 607 1,47 31,4269 1,01% 0,0532 0,92% 201,9 2,0 337,6 20,6 201,9 2,0 GI47MI_14 852 1,75 33,7930 1,07% 0,0513 0,80% 188,0 2,0 254,1 18,3 188,0 2,0 GI47MI_13 393 0,57 13,6653 1,04% 0,0578 0,80% 455,3 4,6 523,1 17,5 455,3 4,6 GI47MI_12 344 0,54 31,3909 1,44% 0,0498 1,48% 202,2 2,9 184,6 34,2 202,2 2,9 GI47MI_11 959 0,18 31,9884 1,02% 0,0510 0,77% 198,4 2,0 241,9 17,6 198,4 2,0 GI47MI_10 1.911 0,19 30,6855 1,28% 0,0509 0,64% 206,7 2,6 235,4 14,6 206,7 2,6 GI47MI_9 783 0,08 31,6322 0,99% 0,0506 0,86% 200,6 2,0 222,6 19,8 200,6 2,0 GI47MI_8 641 0,01 29,1951 1,19% 0,0519 0,96% 217,1 2,5 278,9 21,8 217,1 2,5 GI47MI_7 222 1,09 31,1282 1,21% 0,0547 1,23% 203,8 2,4 399,9 27,4 203,8 2,4 GI47MI_6 377 0,78 16,1792 1,20% 0,0553 0,76% 386,6 4,5 426,1 16,9 386,6 4,5 GI47MI_5 800 0,30 31,2325 0,94% 0,0503 0,80% 203,2 1,9 209,1 18,4 203,2 1,9 GI47MI_4 418 0,86 33,0898 1,09% 0,0497 1,07% 191,9 2,1 182,6 24,8 191,9 2,1 GI47MI_3 699 0,33 13,1661 1,04% 0,0617 0,64% 471,9 4,7 665,1 13,7 471,9 4,7 GI47MI_2 446 0,49 16,0384 1,01% 0,0553 0,74% 389,9 3,8 425,9 16,5 389,9 3,8 GI47MI_1 255 0,73 31,5711 1,16% 0,0509 1,28% 201,0 2,3 238,0 29,2 201,0 2,3
Sample TQB-002
(Analyzed by (LA)ICP-MS). Points of analysis
U ppm
Th U
238U/ 206Pb
1 sigma (% error)
207Pb/ 206Pb
1 sigma (% error)
Pb206/238U (age)
1 sigma (abs err)
207Pb/206Pb (age)
1 sigma (abs err)
Best age Ma
1 sigma abs err Ma
TQB-002_40 2.303 0,63 32,0733 1,65% 0,0497 1,06% 197,9 3,2 180,9 24,4 197,9 3,2 TQB-002_39 1.475 0,30 27,8694 1,90% 0,0589 1,10% 227,3 4,2 564,0 23,9 227,3 4,2 TQB-002_38 3.410 0,36 31,8821 1,57% 0,0495 1,00% 199,1 3,1 170,3 23,2 199,1 3,1 TQB-002_37 7.576 0,67 31,7272 1,74% 0,0501 1,03% 200,0 3,4 201,5 23,8 200,0 3,4 TQB-002_36 3.453 0,39 32,2529 2,31% 0,0514 1,02% 196,8 4,5 260,4 23,2 196,8 4,5 TQB-002_35 1.442 0,22 37,2292 5,75% 0,0518 1,13% 170,9 9,7 277,6 25,7 170,9 9,7 TQB-002_34 219 0,64 31,7931 1,64% 0,0498 1,52% 199,6 3,2 186,3 35,1 199,6 3,2 TQB-002_33 2.580 0,26 31,5751 1,63% 0,0495 1,10% 201,0 3,2 171,8 25,6 201,0 3,2 TQB-002_32 306 1,20 14,3515 1,59% 0,0566 1,12% 434,2 6,7 476,0 24,5 434,2 6,7 TQB-002_31 739 0,22 20,8617 1,61% 0,0545 1,06% 301,8 4,8 389,8 23,7 301,8 4,8 TQB-002_30 366 0,88 32,1327 1,53% 0,0501 1,45% 197,6 3,0 198,3 33,2 197,6 3,0 TQB-002_29 879 0,32 31,9945 1,79% 0,0499 1,14% 198,4 3,5 189,6 26,4 198,4 3,5 TQB-002_28 237 2,29 31,4274 1,82% 0,0502 1,52% 201,9 3,6 202,4 34,8 201,9 3,6 TQB-002_27 1.188 0,35 31,6226 1,81% 0,0504 1,13% 200,7 3,6 212,7 26,0 200,7 3,6 TQB-002_26 6.168 0,29 31,7486 1,58% 0,0495 0,99% 199,9 3,1 171,9 22,9 199,9 3,1 TQB-002_25 566 0,53 32,0605 1,76% 0,0502 1,34% 198,0 3,4 203,3 30,9 198,0 3,4 TQB-002_24 1.234 0,17 41,5696 5,80% 0,0505 1,09% 153,2 8,8 216,1 25,1 153,2 8,8 TQB-002_23 380 0,67 32,1663 1,69% 0,0500 1,32% 197,4 3,3 196,0 30,4 197,4 3,3 TQB-002_22 6.531 0,45 31,9367 1,67% 0,0494 0,99% 198,8 3,3 167,8 22,9 198,8 3,3 TQB-002_21 2.666 0,10 31,5229 1,64% 0,0495 1,16% 201,3 3,3 170,9 26,9 201,3 3,3 TQB-002_20 52 0,28 10,8297 1,96% 0,0596 1,81% 569,4 10,7 587,5 38,7 569,4 10,7 TQB-002_19 61 0,31 11,0592 1,77% 0,0597 1,66% 558,0 9,5 592,2 35,6 558,0 9,5
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TQB-002_18 173 0,43 6,0559 1,65% 0,0732 1,20% 985,2 15,1 1020,4 24,1 1020,4 24,1 TQB-002_17 817 0,63 32,2061 1,68% 0,0508 1,26% 197,1 3,3 233,7 28,7 197,1 3,3 TQB-002_16 1.222 0,39 34,5472 5,15% 0,0500 1,22% 183,9 9,3 196,7 28,1 183,9 9,3 TQB-002_15 319 0,86 31,4801 1,77% 0,0501 1,59% 201,6 3,5 201,0 36,4 201,6 3,5 TQB-002_14 435 0,66 32,2207 1,65% 0,0499 1,39% 197,0 3,2 190,5 32,0 197,0 3,2 TQB-002_13 642 0,54 53,3340 12,41% 0,0535 1,45% 119,7 14,7 348,6 32,4 119,7 14,7 TQB-002_12 407 0,51 32,1979 2,09% 0,0542 1,51% 197,2 4,1 379,7 33,5 197,2 4,1 TQB-002_11 194 0,47 31,8504 1,88% 0,0506 1,66% 199,3 3,7 221,4 38,0 199,3 3,7 TQB-002_10 343 0,32 5,8585 1,84% 0,0858 1,18% 1015,9 17,3 1334,4 22,6 1334,4 22,6 TQB-002_9 1.037 0,17 31,8580 1,76% 0,0508 1,27% 199,2 3,5 231,3 29,0 199,2 3,5 TQB-002_8 6.510 0,20 31,7870 1,69% 0,0494 1,15% 199,7 3,3 166,2 26,6 199,7 3,3 TQB-002_7 7.519 0,14 31,6183 1,80% 0,0517 1,16% 200,7 3,5 272,0 26,3 200,7 3,5 TQB-002_6 423 0,86 32,0081 1,86% 0,0508 1,34% 198,3 3,6 234,0 30,5 198,3 3,6 TQB-002_5 476 0,84 36,0588 8,87% 0,0523 1,35% 176,3 15,4 298,2 30,4 176,3 15,4 TQB-002_4 1.746 0,27 31,6839 1,73% 0,0500 1,20% 200,3 3,4 195,2 27,7 200,3 3,4 TQB-002_3 1.565 0,34 32,3566 1,58% 0,0525 1,22% 196,2 3,0 307,7 27,6 196,2 3,0 TQB-002_2 1.534 0,37 32,3543 1,99% 0,0513 1,29% 196,2 3,8 255,4 29,4 196,2 3,8 TQB-002_1 1.358 0,50 31,3672 1,69% 0,0496 1,25% 202,3 3,4 174,7 29,0 202,3 3,4 TQB-002_0 1.231 0,83 31,1756 1,60% 0,0501 1,25% 203,5 3,2 197,9 28,8 203,5 3,2 TQB-002_1 3.232 0,38 31,9289 1,61% 0,0497 1,17% 198,8 3,2 182,2 27,0 198,8 3,2
Sample TPD71
(Analyzed by (LA)ICP-MS). Points of analysis
U ppm
Th U
238U/ 206Pb
1 sigma (% error)
207Pb/ 206Pb
1 sigma (% error)
Pb206/238U (age)
1 sigma (abs err)
207Pb/206Pb (age)
1 sigma (abs err)
Best age Ma
1 sigma abs err Ma
TPD71_45 185 1,44 32,0301 2,36% 0,0625 1,71% 198,2 4,6 691,4 36,0 198,2 4,6 TPD71_41 191 0,93 31,2527 2,16% 0,0521 1,57% 203,0 4,3 288,6 35,5 203,0 4,3 TPD71_40 381 0,65 3,4383 2,13% 0,1065 1,08% 1645,8 30,9 1740,0 19,7 1740,0 19,7 TPD71_39 142 0,77 32,2836 1,43% 0,0500 1,87% 196,7 2,8 195,4 42,9 196,7 2,8 TPD71_38 121 1,07 31,6329 1,44% 0,0501 1,88% 200,6 2,8 201,3 43,1 200,6 2,8 TPD71_37 162 0,93 32,4919 1,35% 0,0499 1,84% 195,4 2,6 189,8 42,2 195,4 2,6 TPD71_36 163 0,93 31,6985 1,29% 0,0505 1,70% 200,2 2,5 217,1 38,9 200,2 2,5 TPD71_35 193 0,71 31,9629 1,31% 0,0521 1,65% 198,6 2,6 288,7 37,2 198,6 2,6 TPD71_34 127 1,06 32,3588 1,55% 0,0502 1,94% 196,2 3,0 206,1 44,5 196,2 3,0 TPD71_33 150 1,32 31,4281 1,57% 0,0499 2,06% 201,9 3,1 189,9 47,3 201,9 3,1 TPD71_32 197 0,82 31,8868 1,43% 0,0515 1,73% 199,1 2,8 262,1 39,4 199,1 2,8 TPD71_31 93 0,86 32,6091 1,90% 0,0502 2,47% 194,7 3,7 203,5 56,3 194,7 3,7 TPD71_30 169 1,29 31,6776 1,31% 0,0511 1,82% 200,4 2,6 244,8 41,4 200,4 2,6 TPD71_29 219 0,69 31,8258 1,37% 0,0498 1,81% 199,4 2,7 183,6 41,7 199,4 2,7 TPD71_28 104 1,14 32,3979 1,54% 0,0506 2,29% 196,0 3,0 221,7 52,1 196,0 3,0 TPD71_27 200 0,88 32,6764 1,38% 0,0503 1,69% 194,3 2,6 206,6 38,7 194,3 2,6 TPD71_26 168 1,15 32,2339 1,48% 0,0509 1,78% 196,9 2,9 236,2 40,6 196,9 2,9 TPD71_25 236 0,87 31,8650 1,45% 0,0492 1,74% 199,2 2,9 155,9 40,2 199,2 2,9 TPD71_24 138 1,18 31,9894 1,35% 0,0501 2,02% 198,4 2,6 199,1 46,2 198,4 2,6 TPD71_23 165 0,92 32,1465 1,40% 0,0509 2,01% 197,5 2,7 234,7 45,6 197,5 2,7 TPD71_22 174 0,72 31,7294 1,38% 0,0499 1,81% 200,0 2,7 191,9 41,6 200,0 2,7 TPD71_21 107 0,91 32,3444 1,61% 0,0513 2,12% 196,3 3,1 254,7 48,0 196,3 3,1 TPD71_20 180 0,84 30,9928 1,32% 0,0512 1,82% 204,7 2,7 251,6 41,2 204,7 2,7 TPD71_19 127 0,87 31,8855 1,31% 0,0503 2,16% 199,1 2,6 207,1 49,3 199,1 2,6 TPD71_18 134 1,01 31,4202 1,42% 0,0503 1,97% 202,0 2,8 206,9 45,0 202,0 2,8 TPD71_17 144 1,28 31,4126 1,18% 0,0494 1,99% 202,0 2,4 165,0 45,8 202,0 2,4 TPD71_16 105 1,03 32,1221 1,29% 0,0483 2,35% 197,6 2,5 114,9 54,6 197,6 2,5 TPD71_15 194 0,79 31,1441 1,16% 0,0492 1,78% 203,7 2,3 158,8 41,2 203,7 2,3 TPD71_14 139 0,94 31,2615 1,34% 0,0505 2,00% 203,0 2,7 215,9 45,7 203,0 2,7 TPD71_13 83 0,92 31,3700 1,41% 0,0502 2,31% 202,3 2,8 203,7 52,7 202,3 2,8 TPD71_12 105 1,05 31,8467 1,42% 0,0514 2,20% 199,3 2,8 260,6 49,8 199,3 2,8 TPD71_10 92 0,96 31,8680 1,72% 0,0502 2,22% 199,2 3,4 203,5 50,8 199,2 3,4 TPD71_9 122 0,97 31,7366 1,55% 0,0515 2,01% 200,0 3,0 262,7 45,5 200,0 3,0 TPD71_8 102 0,94 32,0022 1,45% 0,0513 2,18% 198,4 2,8 256,1 49,3 198,4 2,8 TPD71_6 139 0,81 32,0958 1,60% 0,0515 1,98% 197,8 3,1 264,8 44,9 197,8 3,1 TPD71_5 192 0,87 31,9257 1,57% 0,0499 1,62% 198,8 3,1 190,0 37,3 198,8 3,1 TPD71_3 129 0,91 31,3759 1,46% 0,0521 1,88% 202,3 2,9 290,1 42,4 202,3 2,9 TPD71_2 110 0,98 31,3744 1,55% 0,0503 2,06% 202,3 3,1 209,0 47,0 202,3 3,1
MANUSCRIP
T
ACCEPTED
ACCEPTED MANUSCRIPT
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
TPD71_1 144 0,90 31,2614 1,47% 0,0502 1,85% 203,0 2,9 206,6 42,3 203,0 2,9
Sample TQB-005
(Analyzed by (LA)ICP-MS). Points of analysis
U ppm
Th U
238U/ 206Pb
1 sigma (% error)
207Pb/ 206Pb
1 sigma (% error)
Pb206/238U (age)
1 sigma (abs err)
207Pb/206Pb (age)
1 sigma (abs err)
Best age Ma
1 sigma abs err Ma
TQB-005_39 571 0,49 9,2648 2,10% 0,0707 0,81% 660,7 13,1 948,8 16,4 660,7 13,1 TQB-005_38 194 1,15 32,5596 1,79% 0,0507 1,50% 195,0 3,4 226,0 34,2 195,0 3,4 TQB-005_37 127 1,05 32,5067 1,73% 0,0513 1,75% 195,3 3,3 253,4 39,7 195,3 3,3 TQB-005_36 52 2,53 13,1858 1,94% 0,0567 1,51% 471,2 8,8 480,6 33,1 471,2 8,8 TQB-005_35 291 0,43 5,9112 1,57% 0,0806 0,75% 1007,5 14,7 1211,6 14,7 1007,5 14,7 TQB-005_34 264 0,60 31,8288 1,94% 0,0507 1,64% 199,4 3,8 226,0 37,5 199,4 3,8 TQB-005_33 115 1,16 31,9007 1,73% 0,0520 2,05% 199,0 3,4 285,4 46,2 199,0 3,4 TQB-005_32 114 0,78 31,6127 1,76% 0,0511 1,97% 200,8 3,5 246,1 44,8 200,8 3,5 TQB-005_31 639 0,42 6,9924 1,54% 0,0727 0,78% 861,7 12,4 1006,4 15,7 861,7 12,4 TQB-005_30 370 1,43 31,4799 1,68% 0,0500 1,23% 201,6 3,3 195,6 28,4 201,6 3,3 TQB-005_29 72 0,67 32,0739 2,25% 0,0493 2,33% 197,9 4,4 164,1 53,5 197,9 4,4 TQB-005_28 102 0,79 31,7847 1,82% 0,0491 1,91% 199,7 3,6 153,8 44,2 199,7 3,6 TQB-005_27 117 0,61 31,7872 1,84% 0,0504 1,81% 199,7 3,6 214,7 41,4 199,7 3,6 TQB-005_26 1.106 0,34 5,1316 1,47% 0,0767 0,67% 1147,7 15,5 1113,3 13,3 1113,3 13,3 TQB-005_25 486 0,72 14,6929 1,57% 0,0561 0,82% 424,5 6,4 458,0 18,0 424,5 6,4 TQB-005_24 247 0,67 4,2266 1,90% 0,0931 0,73% 1369,0 23,3 1489,2 13,8 1489,2 13,8 TQB-005_23 88 1,04 32,3173 1,83% 0,0505 2,07% 196,4 3,5 219,3 47,3 196,4 3,5 TQB-005_22 79 0,95 31,8911 1,85% 0,0528 2,46% 199,0 3,6 322,1 54,8 199,0 3,6 TQB-005_21 168 1,14 31,9780 1,75% 0,0502 1,65% 198,5 3,4 203,4 37,9 198,5 3,4 TQB-005_20 114 0,76 32,2175 1,90% 0,0505 1,95% 197,0 3,7 218,9 44,6 197,0 3,7 TQB-005_19 300 1,76 31,5987 1,53% 0,0499 1,29% 200,8 3,0 192,1 29,7 200,8 3,0 TQB-005_18 67 0,34 4,6091 1,71% 0,0818 0,97% 1265,8 19,6 1239,6 18,8 1239,6 18,8 TQB-005_17 994 0,55 14,1582 1,54% 0,0559 0,71% 440,0 6,5 449,7 15,7 440,0 6,5 TQB-005_16 112 1,49 32,1922 1,86% 0,0522 1,79% 197,2 3,6 296,3 40,3 197,2 3,6 TQB-005_15 376 1,24 31,7214 2,21% 0,0582 1,46% 200,1 4,4 539,1 31,6 200,1 4,4 TQB-005_14 133 1,13 32,1801 1,76% 0,0507 1,64% 197,3 3,4 226,4 37,4 197,3 3,4 TQB-005_13 347 2,14 32,0827 1,45% 0,0637 2,56% 197,9 2,8 730,3 53,4 197,9 2,8 TQB-005_12 169 1,16 31,7902 1,65% 0,0520 1,61% 199,7 3,2 287,3 36,3 199,7 3,2 TQB-005_11 78 0,95 32,3344 1,79% 0,0549 2,63% 196,3 3,5 408,9 57,7 196,3 3,5 TQB-005_10 121 0,93 31,8235 1,89% 0,0522 1,85% 199,4 3,7 293,1 41,7 199,4 3,7 TQB-005_9 269 0,59 32,1454 1,78% 0,0498 1,40% 197,5 3,5 186,5 32,3 197,5 3,5 TQB-005_8 435 2,05 32,0847 2,03% 0,0519 1,34% 197,9 4,0 279,3 30,3 197,9 4,0 TQB-005_7 139 1,34 30,4592 1,80% 0,0767 1,65% 208,2 3,7 1113,2 32,6 208,2 3,7 TQB-005_6 123 0,76 31,8655 1,80% 0,0517 1,59% 199,2 3,5 272,9 36,1 199,2 3,5 TQB-005_5 108 0,74 32,0077 1,75% 0,0498 1,93% 198,3 3,4 184,3 44,3 198,3 3,4 TQB-005_4 680 0,12 6,9974 1,48% 0,0716 0,72% 861,1 11,9 973,9 14,5 861,1 11,9 TQB-005_3 133 0,86 26,1444 6,70% 0,0622 1,26% 242,0 15,9 681,3 26,8 242,0 15,9 TQB-005_2 318 0,53 6,2427 1,55% 0,0718 0,75% 957,8 13,7 981,7 15,2 957,8 13,7 TQB-005_1 175 1,12 31,6772 1,78% 0,0499 1,64% 200,4 3,5 190,2 37,6 200,4 3,5
Sample TQB-003
(Analyzed by (LA)ICP-MS). Points of analysis
U Ppm
Th U
238U/ 206Pb
1 sigma (% error)
207Pb/ 206Pb
1 sigma (% error)
Pb206/238U (age)
1 sigma (abs err)
207Pb/206Pb (age)
1 sigma (abs err)
Best age Ma
1 sigma abs err Ma
TQB-003_40 250 0,90 32,0018 1,52% 0,0508 1,76% 198,4 3,0 229,8 40,1 198,4 3,0 TQB-003_39 406 0,86 31,9801 1,72% 0,0503 1,76% 198,5 3,4 208,9 40,2 198,5 3,4 TQB-003_38 303 1,00 32,1552 1,48% 0,0560 1,71% 197,4 2,9 451,6 37,5 197,4 2,9 TQB-003_37 675 0,85 32,1155 1,66% 0,0495 1,49% 197,7 3,2 173,3 34,4 197,7 3,2 TQB-003_36 260 0,82 31,1086 1,58% 0,0519 1,69% 204,0 3,2 280,0 38,2 204,0 3,2 TQB-003_35 333 0,89 31,4336 1,46% 0,0502 1,66% 201,9 2,9 202,3 38,0 201,9 2,9 TQB-003_34 278 0,84 32,1900 1,60% 0,0508 1,70% 197,2 3,1 230,9 38,8 197,2 3,1 TQB-003_33 169 1,00 31,8821 1,58% 0,0521 1,90% 199,1 3,1 289,8 42,8 199,1 3,1 TQB-003_32 243 1,02 31,2673 1,71% 0,0505 1,76% 202,9 3,4 216,9 40,3 202,9 3,4
MANUSCRIP
T
ACCEPTED
ACCEPTED MANUSCRIPT
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
TQB-003_31 426 0,80 31,9955 1,43% 0,0502 1,59% 198,4 2,8 205,4 36,5 198,4 2,8 TQB-003_30 339 0,80 31,7434 1,59% 0,0510 1,62% 199,9 3,1 239,6 36,9 199,9 3,1 TQB-003_29 287 1,16 32,0627 1,80% 0,0503 1,67% 198,0 3,5 209,9 38,3 198,0 3,5 TQB-003_28 244 1,10 32,2600 1,63% 0,0522 1,77% 196,8 3,2 295,9 39,9 196,8 3,2 TQB-003_27 301 0,87 32,3226 1,44% 0,0509 1,65% 196,4 2,8 235,8 37,6 196,4 2,8 TQB-003_26 1.023 0,52 18,7768 1,42% 0,0571 1,60% 334,5 4,6 494,4 34,8 334,5 4,6 TQB-003_25 763 0,43 24,9518 1,61% 0,0611 1,42% 253,3 4,0 642,9 30,1 253,3 4,0 TQB-003_24 163 0,87 32,3199 1,74% 0,0503 1,94% 196,4 3,4 210,5 44,4 196,4 3,4 TQB-003_23 507 1,09 31,9258 1,70% 0,0502 1,70% 198,8 3,3 205,1 39,1 198,8 3,3 TQB-003_22 285 0,79 31,9925 1,57% 0,0500 1,69% 198,4 3,1 193,9 38,9 198,4 3,1 TQB-003_21 326 0,90 32,0626 1,66% 0,0563 1,79% 198,0 3,2 462,7 39,1 198,0 3,2 TQB-003_20 432 0,62 14,8564 2,28% 0,0604 1,47% 419,9 9,3 617,7 31,4 419,9 9,3 TQB-003_19 220 1,27 32,0617 1,13% 0,0494 1,12% 198,0 2,2 168,4 26,1 198,0 2,2 TQB-003_18 559 0,90 32,0628 0,92% 0,0498 0,87% 198,0 1,8 185,5 20,2 198,0 1,8 TQB-003_17 176 1,05 32,2018 1,25% 0,0488 1,22% 197,1 2,4 137,0 28,4 197,1 2,4 TQB-003_16 397 0,78 32,2941 1,18% 0,0531 1,33% 196,6 2,3 333,6 29,9 196,6 2,3 TQB-003_15 229 0,49 31,8841 1,32% 0,0525 1,59% 199,1 2,6 309,1 35,8 199,1 2,6 TQB-003_14 184 0,94 32,0952 1,41% 0,0495 1,47% 197,8 2,8 173,2 33,9 197,8 2,8 TQB-003_13 148 1,06 32,6154 4,52% 0,0485 1,53% 194,7 8,7 123,3 35,7 194,7 8,7 TQB-003_12 345 0,78 32,0892 1,43% 0,0486 1,01% 197,8 2,8 129,7 23,6 197,8 2,8 TQB-003_11 229 0,80 31,9912 1,35% 0,0515 1,18% 198,4 2,6 263,1 26,9 198,4 2,6 TQB-003_10 379 0,87 31,6825 1,34% 0,0514 0,94% 200,3 2,6 258,2 21,4 200,3 2,6 TQB-003_9 291 0,88 31,7111 1,16% 0,0499 1,07% 200,1 2,3 192,0 24,7 200,1 2,3 TQB-003_8 297 0,81 31,9275 1,03% 0,0490 1,15% 198,8 2,0 145,7 26,8 198,8 2,0 TQB-003_7 257 0,75 31,7602 1,31% 0,0583 1,76% 199,8 2,6 539,4 38,0 199,8 2,6 TQB-003_6 493 0,88 32,1299 1,22% 0,0498 0,91% 197,6 2,4 187,0 21,0 197,6 2,4 TQB-003_5 262 0,83 32,2117 1,39% 0,0510 1,17% 197,1 2,7 241,7 26,7 197,1 2,7 TQB-003_4 247 0,76 31,8603 1,11% 0,0546 1,11% 199,2 2,2 395,1 24,6 199,2 2,2 TQB-003_3 165 0,97 31,7842 1,31% 0,0491 1,52% 199,7 2,6 153,2 35,2 199,7 2,6 TQB-003_2 217 0,85 31,8251 1,13% 0,0507 1,24% 199,4 2,2 227,4 28,4 199,4 2,2 TQB-003_1 281 0,79 32,1064 1,32% 0,0495 1,00% 197,7 2,6 172,9 23,2 197,7 2,6
Sample TQB-004
(Analyzed by (LA)ICP-MS). Points of analysis
U Ppm
Th U
238U/ 206Pb
1 sigma (% error)
207Pb/ 206Pb
1 sigma (% error)
Pb206/238U (age)
1 sigma (abs err)
207Pb/206Pb (age)
1 sigma (abs err)
Best age Ma
1 sigma abs err Ma
TQB-004_44 2.405 0,62 31,6619 1,41% 0,0495 1,10% 200,5 2,8 170,5 25,5 200,5 2,8 TQB-004_43 1.892 0,56 31,6942 1,48% 0,0493 1,12% 200,3 2,9 164,0 25,9 200,3 2,9 TQB-004_42 389 0,53 31,5890 1,44% 0,0508 1,33% 200,9 2,8 233,6 30,3 200,9 2,8 TQB-004_41 1.260 0,19 28,8174 2,23% 0,0533 1,20% 219,9 4,8 342,5 27,0 219,9 4,8 TQB-004_40 2.422 0,45 31,8873 1,35% 0,0496 1,10% 199,1 2,6 176,8 25,5 199,1 2,6 TQB-004_39 1.153 0,46 13,0911 1,72% 0,0556 1,13% 474,5 7,9 436,1 25,0 474,5 7,9 TQB-004_38 238 1,43 31,9773 1,49% 0,0511 1,51% 198,5 2,9 243,6 34,3 198,5 2,9 TQB-004_37 405 1,11 30,8330 1,61% 0,0501 1,32% 205,8 3,3 197,6 30,5 205,8 3,3 TQB-004_36 632 0,43 58,4176 18,91% 0,0518 1,44% 109,4 20,5 278,0 32,7 109,4 20,5 TQB-004_35 667 2,19 31,6083 1,36% 0,0500 1,26% 200,8 2,7 193,0 29,1 200,8 2,7 TQB-004_34 858 0,18 13,6677 1,52% 0,0556 1,11% 455,2 6,7 437,2 24,6 455,2 6,7 TQB-004_33 1.409 0,13 31,6108 1,37% 0,0497 1,14% 200,8 2,7 180,5 26,3 200,8 2,7 TQB-004_32 353 0,62 32,0492 1,47% 0,0488 1,38% 198,1 2,9 138,0 32,2 198,1 2,9 TQB-004_31 1.084 0,19 25,7499 1,63% 0,0532 1,13% 245,6 3,9 339,3 25,4 245,6 3,9 TQB-004_30 634 0,80 29,4855 1,41% 0,0503 1,34% 215,0 3,0 208,1 30,9 215,0 3,0 TQB-004_29 848 0,30 31,6185 1,47% 0,0500 1,24% 200,7 2,9 197,2 28,6 200,7 2,9 TQB-004_28 383 0,69 31,9074 1,49% 0,0515 1,43% 198,9 2,9 264,9 32,5 198,9 2,9 TQB-004_27 1.111 0,28 31,7166 1,47% 0,0495 1,21% 200,1 2,9 173,0 28,0 200,1 2,9 TQB-004_26 355 0,86 13,7077 1,51% 0,0562 1,28% 453,9 6,6 461,9 28,1 453,9 6,6 TQB-004_25 1.039 0,23 31,5694 1,38% 0,0504 1,21% 201,0 2,7 211,9 27,8 201,0 2,7 TQB-004_24 644 0,81 30,7097 1,44% 0,0547 1,34% 206,6 2,9 400,1 29,8 206,6 2,9 TQB-004_23 830 0,75 30,9873 1,45% 0,0496 1,21% 204,7 2,9 176,9 28,1 204,7 2,9 TQB-004_22 486 0,22 32,0469 1,52% 0,0521 1,06% 198,1 3,0 288,9 24,0 198,1 3,0 TQB-004_21 475 0,77 13,9494 1,25% 0,0592 0,77% 446,3 5,4 576,0 16,6 446,3 5,4 TQB-004_20 331 1,41 27,5479 4,24% 0,0531 1,46% 229,9 9,6 333,4 32,7 229,9 9,6 TQB-004_19 712 0,84 16,6307 1,42% 0,0558 0,77% 376,4 5,2 443,5 17,1 376,4 5,2 TQB-004_18 604 1,29 32,6065 1,26% 0,0503 0,95% 194,7 2,4 210,0 21,9 194,7 2,4
MANUSCRIP
T
ACCEPTED
ACCEPTED MANUSCRIPT
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
TQB-004_17 604 1,29 32,6065 1,26% 0,0503 0,95% 194,7 2,4 210,0 21,9 194,7 2,4 TQB-004_16 1.405 1,05 32,1855 1,34% 0,0518 0,78% 197,2 2,6 278,0 17,8 197,2 2,6 TQB-004_15 1.179 0,26 32,0068 1,18% 0,0497 0,81% 198,3 2,3 179,2 18,7 198,3 2,3 TQB-004_14 287 0,59 7,0891 1,31% 0,0685 0,75% 850,7 10,4 883,0 15,4 850,7 10,4 TQB-004_13 3.259 0,32 32,1185 1,26% 0,0497 0,73% 197,6 2,4 181,3 16,8 197,6 2,4 TQB-004_12 352 0,38 23,4500 2,08% 0,0544 0,86% 269,2 5,5 386,7 19,1 269,2 5,5 TQB-004_11 530 0,42 14,8879 1,45% 0,0557 0,82% 419,1 5,9 441,7 18,2 419,1 5,9 TQB-004_10 242 0,79 32,1944 1,41% 0,0505 1,27% 197,2 2,7 217,8 29,1 197,2 2,7 TQB-004_9 3.058 0,09 30,5526 1,24% 0,0498 0,70% 207,6 2,5 186,1 16,2 207,6 2,5 TQB-004_8 695 0,38 48,8333 11,09% 0,0527 1,26% 130,7 14,3 314,0 28,5 130,7 14,3 TQB-004_7 5.972 0,24 32,3636 1,21% 0,0498 0,70% 196,2 2,3 185,3 16,1 196,2 2,3 TQB-004_6 314 0,38 15,5783 1,32% 0,0642 1,61% 401,1 5,1 747,3 33,7 401,1 5,1 TQB-004_5 2.317 0,20 32,1336 1,30% 0,0502 0,70% 197,6 2,5 205,3 16,3 197,6 2,5 TQB-004_4 470 1,32 30,6635 1,28% 0,0497 0,95% 206,9 2,6 179,6 21,9 206,9 2,6 TQB-004_3 332 0,45 14,5925 1,32% 0,0565 0,88% 427,3 5,4 470,3 19,5 427,3 5,4 TQB-004_2 182 0,95 32,7982 1,36% 0,0503 1,46% 193,6 2,6 208,9 33,5 193,6 2,6 TQB-004_1 1.223 0,16 32,8843 1,21% 0,0495 0,81% 193,1 2,3 170,4 18,9 193,1 2,3
Sample TQB-001
(Analyzed by (LA)ICP-MS). Points of analysis
U Ppm
Th U
238U/ 206Pb
1 sigma (% error)
207Pb/ 206Pb
1 sigma (% error)
Pb206/238U (age)
1 sigma (abs err)
207Pb/206Pb (age)
1 sigma (abs err)
Best age Ma
1 sigma abs err Ma
TQB-001_40 689 0,20 13,0959 1,95% 0,0655 0,57% 474,4 8,9 790,6 11,9 474,4 8,9 TQB-001_39 473 0,45 54,1581 18,11% 0,0502 1,17% 117,9 21,1 204,1 26,9 117,9 21,1 TQB-001_38 2.088 0,49 31,9291 1,84% 0,0497 0,79% 198,8 3,6 181,8 18,4 198,8 3,6 TQB-001_37 2.013 0,28 32,0928 1,42% 0,0502 0,55% 197,8 2,8 204,1 12,6 197,8 2,8 TQB-001_36 1.144 0,29 32,2917 1,42% 0,0502 0,63% 196,6 2,8 202,5 14,6 196,6 2,8 TQB-001_35 3.554 0,14 32,7041 2,10% 0,0507 0,48% 194,2 4,0 227,3 11,1 194,2 4,0 TQB-001_34 584 0,51 32,2716 1,58% 0,0508 0,79% 196,7 3,1 230,0 18,0 196,7 3,1 TQB-001_33 976 0,38 28,5101 3,34% 0,0524 1,03% 222,2 7,3 302,1 23,3 222,2 7,3 TQB-001_32 2.096 0,30 32,3580 1,46% 0,0499 0,57% 196,2 2,8 191,7 13,1 196,2 2,8 TQB-001_31 1.182 0,50 31,4534 1,46% 0,0512 0,69% 201,8 2,9 248,0 15,9 201,8 2,9 TQB-001_30 256 1,34 31,3338 5,28% 0,0489 1,08% 202,5 10,5 141,4 25,1 202,5 10,5 TQB-001_29 2.293 0,18 32,2994 1,43% 0,0504 0,53% 196,6 2,8 214,2 12,2 196,6 2,8 TQB-001_28 753 0,30 18,5778 2,39% 0,0555 0,59% 338,0 7,9 434,4 13,1 338,0 7,9 TQB-001_27 743 0,40 30,7838 1,44% 0,0509 0,74% 206,1 2,9 235,9 17,1 206,1 2,9 TQB-001_26 233 0,90 31,9675 1,48% 0,0495 1,19% 198,6 2,9 172,4 27,6 198,6 2,9 TQB-001_25 1.097 0,35 32,1382 1,60% 0,0515 0,74% 197,5 3,1 262,0 16,9 197,5 3,1 TQB-001_24 640 0,52 32,2790 1,74% 0,0515 0,88% 196,7 3,4 263,3 20,0 196,7 3,4 TQB-001_23 369 0,75 32,6875 1,47% 0,0504 0,86% 194,3 2,8 211,2 19,8 194,3 2,8 TQB-001_22 1.353 0,44 32,2927 1,49% 0,0501 0,58% 196,6 2,9 200,9 13,4 196,6 2,9 TQB-001_21 597 0,30 32,2529 1,61% 0,0501 1,24% 196,8 3,1 200,2 28,6 196,8 3,1 TQB-001_20 4.784 0,20 31,3978 1,56% 0,0496 1,10% 202,1 3,1 178,5 25,4 202,1 3,1 TQB-001_19 1.210 0,29 32,7818 1,69% 0,0501 1,17% 193,7 3,2 201,5 26,9 193,7 3,2 TQB-001_18 891 0,71 32,4213 1,59% 0,0514 1,22% 195,8 3,1 260,2 27,7 195,8 3,1 TQB-001_17 598 0,55 32,8593 1,68% 0,0502 1,27% 193,3 3,2 205,6 29,2 193,3 3,2 TQB-001_16 2.499 0,21 32,0452 1,62% 0,0501 1,12% 198,1 3,2 201,4 25,9 198,1 3,2 TQB-001_15 2.611 0,19 31,8824 1,64% 0,0500 1,14% 199,1 3,2 194,0 26,3 199,1 3,2 TQB-001_14 635 0,28 21,9491 2,29% 0,0539 1,37% 287,2 6,4 366,3 30,6 287,2 6,4 TQB-001_13 329 0,98 32,4122 1,71% 0,0505 1,62% 195,9 3,3 217,1 37,1 195,9 3,3 TQB-001_12 1.440 0,16 32,0348 1,64% 0,0502 1,27% 198,2 3,2 204,0 29,1 198,2 3,2 TQB-001_11 792 0,25 39,8528 9,50% 0,0529 1,27% 159,8 15,0 324,6 28,6 159,8 15,0 TQB-001_10 877 0,66 32,1081 1,61% 0,0501 1,29% 197,7 3,1 201,2 29,7 197,7 3,1 TQB-001_9 904 0,08 32,3569 1,56% 0,0508 1,25% 196,2 3,0 229,8 28,7 196,2 3,0 TQB-001_8 741 0,29 6,5927 1,90% 0,0725 1,08% 910,4 16,1 1000,0 21,9 910,4 16,1 TQB-001_7 625 0,33 14,3813 1,71% 0,0565 1,16% 433,4 7,2 470,3 25,4 433,4 7,2 TQB-001_6 608 0,76 32,4403 1,83% 0,0502 1,32% 195,7 3,5 202,6 30,4 195,7 3,5 TQB-001_5 954 0,47 32,3285 1,87% 0,0503 1,35% 196,4 3,6 210,0 31,1 196,4 3,6 TQB-001_4 1.746 0,73 32,7904 1,72% 0,0503 1,16% 193,7 3,3 207,5 26,7 193,7 3,3 TQB-001_3 408 0,51 33,0500 1,61% 0,0514 1,43% 192,2 3,1 258,1 32,6 192,2 3,1 TQB-001_2 570 0,33 14,4095 1,94% 0,0555 1,15% 432,5 8,1 431,5 25,3 432,5 8,1 TQB-001_1 7.729 0,31 32,1956 1,67% 0,0502 1,12% 197,2 3,2 205,8 25,7 197,2 3,2
MANUSCRIP
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ACCEPTED
ACCEPTED MANUSCRIPT
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
Sample TB-CV-008 (Detrital zircons)
(Analyzed by (LA)ICP-MS)
Pb207 /U235
2 sigma
Pb206/ U238
2 sigma rho
Pb207 /Pb206
2 sigma
Pb207 /U235
2 sigma
Pb206/ U238
2 sigma
Pb207/ Pb206
2 sigma Disc Ma 2 Th/U
202
Hg
204
Pb 206Pb
207
Pb
208
Pb 232Th 235U 238U
1 0,22192 0,0283
6 0,03164 0,0012 0,296780245 0,0474 0,0059 203,5 23,58 200,8 7,5 68,8 284,56 1,3 200,8 3,75 0,395253 0 0 3854 183 1276 50228 760 126318
2 0,59123 0,0416
6 0,0761 0,00178 0,3319499 0,05566 0,00342 471,7 26,58 472,8 10,62 438,4 133,5 -0,2 472,8 5,31 0,198837 0 0 6250 349 1057 17064 544 85275
3 1,75074 0,0501 0,173 0,00202 0,408027275 0,07226 0,00148 1027,4 18,5 1028,6 11,08 993,3 41,44 -0,1 1028,6 5,54 0,105732 76 0 26386 1917 2315 16874 1008 158584
4 3,37799 0,3318 0,27353 0,00774 0,288083227 0,0952 0,0052 1499,3 76,96 1558,7 39,18 1532 100,98 -1,7 1532 100,98 0,43212 47 37 5274 504 1735 8734 137 20075
5 0,5574 0,0167
4 0,07461 0,00096 0,428435751 0,05587 0,00146 449,8 10,92 463,9 5,72 446,7 57,12 -3,1 463,9 2,86 0,190138 0 0 37333 2097 5635 99857 3476 521705
6 2,07827 0,0429
4 0,19499 0,00198 0,491465209 0,07781 0,00118 1141,7 14,16 1148,3 10,68 1142 30,14 -0,6 1148,3 5,34 0,109109 0 27 60630 4742 5293 35701 2115 325091
7 2,11315 0,0492
2 0,19935 0,00212 0,456571015 0,07818 0,0013 1153,1 16,06 1171,8 11,42 1151,4 32,62 -1,6 1171,8 5,71 0,132616 92 28 124501 9784 12767 87284 4298 653872
8 2,0451 0,0479
4 0,19079 0,00204 0,456132564 0,0783 0,00132 1130,7 15,98 1125,7 11,04 1154,5 33,16 0,4 1125,7 5,52 0,116858 0 0 43178 3398 3843 27908 1545 237275
9 2,00067 0,0378
6 0,18327 0,00182 0,52477708 0,07837 0,00112 1115,7 12,82 1084,8 9,92 1156,3 28,46 2,8 1084,8 4,96 0,093966 2 0 77285 6088 5649 41868 2833 442734
10 1,73251 0,0682
8 0,16799 0,0024 0,362501701 0,07404 0,00204 1020,7 25,38 1001 13,26 1042,7 55,16 1,9 1001 6,63 0,146107 9 11 14585 1085 1772 13423 584 91287
11 0,22599 0,0092 0,0321 0,00052 0,397923608 0,05025 0,00198 206,9 7,62 203,7 3,24 206,6 90,02 1,5 203,7 1,62 0,269144 0 30 20154 1017 4269 179287 4214 661925
12 1,7015 0,0403
8 0,16939 0,00184 0,457715578 0,07257 0,00128 1009,1 15,18 1008,8 10,14 1002,1 35,6 0,0 1008,8 5,07 0,202455 0 7 40096 2924 6512 50923 1610 249918
13 0,56611 0,0137
8 0,07272 0,00084 0,474544588 0,05666 0,00122 455,5 8,94 452,5 5 477,5 47,7 0,7 452,5 2,5 0,030606 0 0 36877 2099 954 16516 3481 536153
14 4,71216 0,1113 0,32415 0,0034 0,444076463 0,10771 0,00156 1769,4 19,78 1809,9 16,52 1761 26,36 -2,3 1809,9 8,26 0,207276 10 22 68270 7389 11298 46528 1474 223000
15 3,99372 0,1858
2 0,28552 0,00434 0,326691889 0,10164 0,00256 1632,9 37,78 1619,1 21,74 1654,3 46,16 2,1 1654,3 46,16 0,181881 19 0 38243 3905 5707 25998 920 142020
16 0,61377 0,0355
6 0,07683 0,00154 0,345966296 0,05766 0,00292 485,9 22,38 477,2 9,18 516,4 109,7 1,8 477,2 4,59 0,24849 9 0 7489 433 1373 25920 667 103643
17 1,66019 0,0388 0,16668 0,00182 0,467211974 0,07227 0,00126 993,4 14,82 993,8 10,02 993,4 35,36 0,0 993,8 5,01 0,096647 0 1 57613 4182 4516 35802 2383 368057
18 0,22406 0,0239
2 0,03229 0,00114 0,330704392 0,05037 0,00522 205,3 19,84 204,9 7,12 212,1 232 0,2 204,9 3,56 0,808957 0 35 4567 231 2883 122794 977 150816
19 0,65532 0,0314 0,07964 0,00136 0,35639486 0,05782 0,0024 511,7 19,26 494 8,14 522,8 90,02 3,5 494 4,07 0,247205 0 34 9280 539 2017 30953 780 124432
20 1,45382 0,1238
2 0,15806 0,00438 0,325365853 0,07278 0,00444 911,5 51,24 946 24,34 1007,9 121,38 -3,8 946 12,17 0,002388 26 11 6760 494 13 110 323 45736
21 0,22126 0,0104
4 0,03153 0,00052 0,349527847 0,05037 0,00232 203 8,68 200,1 3,28 211,9 105,1 1,4 200,1 1,64 0,298544 0 3 7482 378 1879 76478 1631 254539
22 1,60255 0,0669 0,15969 0,00238 0,357013556 0,07113 0,00214 971,2 26,1 955,1 13,28 961,2 60,76 1,7 955,1 6,64 0,309195 0 8 13299 950 3104 27830 566 89442
23 0,59938 0,0554
4 0,07636 0,00226 0,31997905 0,0569 0,00464 476,8 35,2 474,4 13,56 487,2 176,26 0,5 474,4 6,78 0,148673 0 0 4397 251 566 9268 401 61937
24 0,58204 0,0404
4 0,07503 0,0018 0,345286218 0,05677 0,00344 465,8 25,96 466,4 10,8 482 132,32 -0,1 466,4 5,4 0,250239 25 23 6732 383 1506 24344 632 96651
25 2,40905 0,0695
6 0,21064 0,00252 0,414329576 0,08304 0,00162 1245,3 20,72 1232,2 13,4 1270,1 37,42 1,1 1232,2 6,7 0,151266 0 0 67233 5606 8431 52417 2234 344287
26 3,23579 0,1223
8 0,25555 0,00348 0,360058641 0,09307 0,00212 1465,8 29,34 1467 17,9 1489,3 42,62 -0,1 1467 8,95 0,286814 53 15 32586 3044 7079 39938 909 138338
27 1,86342 0,0538
8 0,17636 0,00214 0,419659297 0,07609 0,00158 1068,2 19,1 1047 11,72 1097,4 41,4 2,0 1047 5,86 0,122294 18 0 26073 1991 2496 19770 1034 160626
28 1,51387 0,0319
6 0,15687 0,00168 0,507284038 0,07063 0,00118 936 12,9 939,4 9,32 946,7 33,84 -0,4 939,4 4,66 0,129952 17 4 56723 4021 5634 51460 2575 393416
29 2,61964 0,0675
8 0,22203 0,00252 0,439959103 0,08496 0,0015 1306,2 18,96 1292,6 13,3 1314,6 34,14 1,0 1292,6 6,65 0,173597 62 0 60324 5144 7726 51723 1907 296041
30 1,59782 0,0622
2 0,16392 0,00238 0,372857478 0,07124 0,002 969,4 24,32 978,5 13,16 964,3 56,92 -0,9 978,5 6,58 0,365276 70 0 16638 1189 4628 40721 724 110756
31 0,53727 0,0170
6 0,07005 0,00094 0,422603684 0,05567 0,00158 436,6 11,26 436,5 5,62 438,8 61,5 0,0 436,5 2,81 0,289494 0 0 16913 944 3563 76989 1716 264227
32 0,22874 0,0157
4 0,03199 0,0007 0,317995657 0,05021 0,00338 209,2 13 203 4,38 204,8 152,64 3,0 203 2,19 0,496979 0 28 4138 208 1714 70906 891 141783
33 2,37066 0,0662
2 0,21248 0,00252 0,424582978 0,08189 0,00158 1233,8 19,94 1242 13,42 1242,8 37,66 -0,7 1242 6,71 0,092087 0 25 34090 2801 2480 16323 1156 176101
34 2,19283 0,0487
4 0,19995 0,00216 0,48601736 0,0792 0,0013 1178,8 15,5 1175 11,64 1177,2 32,5 0,3 1175 5,82 0,127101 19 0 57577 4576 5771 40491 2046 316528
MANUSCRIP
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ACCEPTED
ACCEPTED MANUSCRIPT
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
35 1,7203 0,0466 0,16857 0,002 0,437993819 0,07273 0,00146 1016,1 17,4 1004,2 11,04 1006,3 40,48 1,2 1004,2 5,52 0,130354 71 0 31044 2265 3246 26595 1293 202729
36 0,554 0,0229
4 0,07337 0,00116 0,381817493 0,0563 0,00208 447,6 14,98 456,5 6,9 463,3 81,36 -2,0 456,5 3,45 0,198785 0 0 9582 541 1615 28852 962 144180
37 0,55147 0,0165
8 0,07178 0,00094 0,435573816 0,05624 0,0015 446 10,86 446,9 5,62 461 58,84 -0,2 446,9 2,81 0,088484 0 0 18672 1053 1331 25618 1886 287636
38 1,88329 0,0397
4 0,18255 0,00196 0,508819295 0,07531 0,00124 1075,2 14 1080,9 10,7 1076,9 32,66 -0,5 1080,9 5,35 0,208229 37 21 67180 5075 10457 85410 2665 407509
39 0,21826 0,0157
4 0,03229 0,00074 0,317784783 0,05019 0,00356 200,5 13,12 204,9 4,58 203,6 160,22 -2,2 204,9 2,29 0,421544 0 17 3686 185 1186 53719 842 126592
40 0,53513 0,0225
2 0,07058 0,00116 0,390541552 0,05582 0,00208 435,2 14,9 439,6 6,92 445 81,08 -1,0 439,6 3,46 0,349081 26 2 14461 809 4104 79963 1501 227566
41 0,21008 0,0200
6 0,03073 0,00102 0,347609304 0,04953 0,00462 193,6 16,84 195,1 6,36 172,8 210,68 -0,8 195,1 3,18 0,279875 4 24 5937 294 1446 60631 1397 215239
42 0,60335 0,0189
2 0,07717 0,00102 0,42150221 0,05698 0,00156 479,4 11,98 479,2 6,14 490,2 60,88 0,0 479,2 3,07 0,157234 56 0 17781 1016 2319 40680 1679 257043
43 1,52152 0,0265 0,15739 0,00162 0,590975764 0,07108 0,00104 939,1 10,66 942,3 9 959,8 29,92 -0,3 942,3 4,5 0,203972 17 15 159650 11381 23799 232674 7472 1133244
44 1,27354 0,0785
8 0,12453 0,00272 0,353993658 0,07255 0,00334 834 35,1 756,6 15,6 1001,3 92,08 9,3 756,6 7,8 0,093855 0 23 22048 1604 2033 18711 1260 198101
45 2,54507 0,0783 0,21945 0,00278 0,411762868 0,08514 0,00178 1285 22,42 1279 14,68 1318,6 40,44 0,5 1279 7,34 0,194043 0 0 30651 2616 4381 30570 1030 156512
46 0,53637 0,0193 0,07102 0,00106 0,414793906 0,0562 0,00178 436 12,76 442,3 6,36 459,3 69,98 -1,4 442,3 3,18 0,080895 61 1 31118 1753 1954 40104 3287 492465
47 0,59669 0,0491
2 0,07749 0,00222 0,348014801 0,05749 0,00412 475,1 31,24 481,1 13,28 509,9 154,24 -1,3 481,1 6,64 0,272315 42 0 8778 505 1862 34959 854 127523
48 0,22145 0,0111
2 0,03149 0,0006 0,37944557 0,05024 0,00244 203,1 9,24 199,9 3,8 206,3 110,78 1,6 199,9 1,9 0,457572 0 19 12382 623 4252 204140 2842 443295
49 1,94545 0,0420
2 0,18428 0,00204 0,512526103 0,07768 0,00132 1096,9 14,48 1090,3 11,08 1138,8 33,38 0,6 1090,3 5,54 0,016076 4 0 115075 8961 1401 11409 4656 705033
50 2,61299 0,2023
2 0,22302 0,00538 0,311556915 0,08301 0,0039 1304,3 56,86 1297,8 28,32 1269,4 90,34 0,5 1297,8 14,16 0,198775 32 8 26310 2189 3901 26684 848 133394
51 1,68424 0,0397
4 0,17006 0,00194 0,483476834 0,07252 0,00134 1002,6 15,04 1012,5 10,74 1000,6 37,1 -1,0 1012,5 5,37 0,230104 0 0 58644 4262 10132 90584 2571 391095
52 1,491 0,0548
4 0,15692 0,00226 0,391570835 0,07035 0,00194 926,7 22,36 939,6 12,54 938,6 56,3 -1,4 939,6 6,27 0,262002 0 0 15162 1069 3200 28946 729 109751
53 3,13858 0,1049
6 0,24486 0,00322 0,393230692 0,09077 0,00198 1442,2 25,74 1411,9 16,7 1441,6 41,4 2,1 1411,9 8,35 0,150367 25 0 23750 2160 2730 16697 701 110341
54 0,55921 0,0158
6 0,07319 0,00094 0,452843202 0,05616 0,0014 451 10,32 455,3 5,66 458,5 54,22 -1,0 455,3 2,83 0,27381 53 4 23505 1323 4978 100848 2416 365898
55 3,48325 0,1035
4 0,2609 0,00324 0,417779779 0,09488 0,00188 1523,4 23,46 1494,5 16,56 1525,7 36,94 1,9 1494,5 8,28 0,343924 29 0 35626 3387 9633 53929 994 155811
56 2,64442 0,1728 0,22042 0,0047 0,326312383 0,08687 0,00358 1313,1 48,14 1284,1 24,8 1357,7 78,44 2,2 1284,1 12,4 0,358603 8 9 7292 634 1946 13666 246 37863
57 3,34291 0,1011 0,25782 0,00326 0,418094568 0,09423 0,0019 1491,1 23,64 1478,7 16,68 1512,8 37,74 2,3 1512,8 37,74 0,205221 0 0 83127 7848 11230 76343 2414 369589
58 0,55988 0,0232 0,07208 0,00116 0,388374029 0,05605 0,00206 451,4 15,1 448,6 6,98 454 79,84 0,6 448,6 3,49 0,363585 38 13 11456 643 3153 66780 1183 182488
59 4,63014 0,1876
4 0,3187 0,00462 0,357707965 0,10662 0,00248 1754,7 33,84 1783,4 22,56 1742,5 42,44 -1,6 1783,4 11,28 0,32102 0 0 53617 5727 12546 62507 1276 193438
60 2,66725 0,0809
2 0,23067 0,00294 0,420111011 0,08588 0,00182 1319,4 22,4 1338 15,44 1335,4 40,74 -1,4 1338 7,72 0,15501 0 0 33941 2920 4272 26441 1131 169445
61 0,21897 0,0204
8 0,03233 0,0009 0,29764012 0,04931 0,00454 201,1 17,06 205,1 5,64 162,5 208,22 -2,0 205,1 2,82 0,442724 0 0 2975 146 1120 47371 696 106303
62 0,56936 0,0308 0,07268 0,0014 0,356081453 0,05586 0,0027 457,6 19,94 452,3 8,4 446,5 105 1,2 452,3 4,2 0,14898 0 0 7264 406 772 17337 741 115630
63 0,56331 0,0186
6 0,0709 0,00102 0,434299929 0,05632 0,00162 453,7 12,12 441,6 6,08 464,1 63,82 2,7 441,6 3,04 0,216927 7 9 36523 2060 5179 130306 3807 596883
MANUSCRIP
T
ACCEPTED
ACCEPTED MANUSCRIPT
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
APPENDIX B.
Whole rock geochemical data of late Triassic-early Jurassic Igneous rocks. Vetas-California Mining District (VCMD). Santander Massif. Colombia Eastern Cordillera.
SAMPLE GE-20-M1 GG-12-M6 GC-74-M1 7-1-1-89 10-1-5-89 TC-CV-006 TB-CV-054 TB-CV-090 GE-10-M1 GI-36-M1 GB-63-M1 HAM-41-1 TB-CV-053 ROCK Alaskite-I Intermediate igneous rocks Alaskite-II
Latitude
Longitude
7° 19’ 00,3’’
72°53’56,4’’
7° 19' 33,0’’
72°54' 34,2"
7° 20' 22,6"
72°56' 53,9"
Dörr et al., (1995)
7° 19’ 36,6’’
72°54’40,5’’
7° 18’ 05,2’’
72°54’29.1’’ 7°21’42,6’’
72°53’ 53,8’’
7° 19' 55,1"
72° 54' 56,8"
7° 19' 59,5"
72°54' 18,6"
7° 20' 31,0"
72°56' 55,7" 7° 20' 06,8"
72° 54' 15,3"
7° 18’10,1’’
72° 54’30,2’’
Local
Coordinates**
X=1.301.027
Y= 1.130.134
Z=~2704mosl
X=1.302.144
Y=1.128.792
Z=~2508mosl
X=1.303.537
Y=1.124.680
Z=~2081mosl
X=1.302.137
Y=1.128.779
Z=~2480mosl
X=1.299.333
Y=1.129.135
Z=~3720mosl
X=1.306.015
Y=1.130.201
Z=~2910mosl
X=1.302.707
Y=1.128.275
Z=~2393mosl
X=1.302.845
Y=1.129.448
Z=~2651mosl
X=1.303.787
Y=1.124.621
Z=~2035mosl
X=1.303.071
Y=1.129.549
Z=~2640mosl
X=1.299.492
Y=1.129.100
Z=~3720mosl
Geographic
location
California-
Vetas road
California-
Vetas road
La Laguna
Creek
(southern
California
town)
California-
Vetas road
Páramo Rico Móngora California-
Vetas road
Móngora-La
Francia path
La Laguna
Creek
(southern
California
town)
La Plata
Creek
Páramo Rico
SiO2 75,14 70,2 73,61 57.0 54.9 55.22 58.67 60.39 75,82 75,25 73,78 75,01 72,65
Al2O3 13,63 14,34 13,97 17.8 17.0 17.35 16.96 15.71 12,94 13,38 14,02 13,25 14,36
Fe2O3 1,07 2,47 1,43 7.45 8.21 8.35 7.04 6.26 0,64 0,53 1,22 1,02 1,77
MgO 0,12 0,43 0,32 3.17 3.56 3.84 3.15 2.99 0,09 0,06 0,22 0,06 0,3
CaO 0,89 1,02 0,32 5.50 6.36 6.66 5.45 5.22 0,14 0,2 0,4 0,16 0,88
Na2O 2,9 1,73 2,8 3.33 3.05 3.13 3.07 2.76 1,15 1,43 2,91 1,31 2,72
K2O 5,12 7,98 6,15 2.92 2.40 2.45 2.9 3.64 8,14 8,01 5,97 7,76 5,74
TiO2 0,16 0,22 0,16 1.01 1.12 1.21 0.99 0.91 0,13 0,14 0,21 0,13 0,19
P2O5 0,07 0,22 0,11 0.32 0.33 0.37 0.31 0.27 0,06 0,06 0,08 0,09 0,08
MnO 0,01 0,03 0,02 0.12 0.13 0.14 0.13 0.13 * * 0,02 * 0,04
Cr2O3 0,002 0,002 0,002 * * 0.005 0.005 0.007 0,002 * * 0,004 *
LOI 0,8 1 1 1.49 0.68 0.9 1 1.4 0,8 0,8 1 1,1 1,1
Sum 99,91 99,64 99,89 100,11 97,74 99.63 99.68 99.69 99,91 99,86 99,83 99,89 99,83
Ba 365 2157 676 * * 2157 1512 913 593 674 843 682 685
Co 0.6 2.5 2.1 15 * 2.5 2.5 18.4 0.2 0.4 1.3 0.4 1,5
Cs 3.3 1 2.4 * * 1 3.6 2.4 1.1 1.5 3.5 1.8 4,8
Ga 15.8 12.6 14.7 22 22 12.6 22.5 22.2 13.5 13.1 15.9 13.2 18,2
Hf 3.3 7.3 3.7 * * 7.3 4.2 5.5 3.1 3.3 3.6 2.8 4,1
Nb 14.4 6.1 10.5 11 12 6.1 12.4 11.2 10.9 10.6 14.3 14.7 13,6
Rb 220.6 145.2 203.5 107 101 145.2 77.9 131.3 169.1 203.4 203.8 194.8 287,7
Sr 88.1 375.3 122.1 693 665 375.3 1020.1 610.2 151 130.5 158.3 120.2 120,3
Ta 1.5 0.5 0.9 * * 0.5 0.9 0.6 1 0.9 1 1.4 1,4
Th 24 40 22.4 11 5 40 16.4 11 23.2 26.6 29.5 23.5 29,4
U 4.1 3.6 4.9 * * 3.6 2.1 2.2 5.1 3.9 4.7 3.8 7,1
V 15 41 <8 * * 41 66 181 18 21 12 22 13
Zr 90.1 271.5 98.2 235 196 271.5 148.4 225 87 89.9 122.3 78.7 129,3
Y 19.6 14.7 15 37 32 14.7 13.1 24.6 22.7 24.2 10.9 19 22,6
Pb 2.4 3.7 13.1 12 11 3.7 0.8 2.4 1.8 2.9 4.7 2.7 6
Ni 1.9 2.2 1.7 12 12 2.2 1.8 8.4 0.8 0.6 1.2 2 1
Sc 3 3 3 * * 3 4 16 3 3 3 3 4
La 28.2 68.5 31.9 * * 68.5 44.4 44.8 32 35.2 35 30.6 46,3
Ce 56.6 140.1 67.5 * * 140.1 84.9 91.1 63.2 71.9 76.9 65.2 100
Pr 6.54 15.07 7.76 * * 15.07 8.88 10.17 7.22 8.28 7.95 7.25 10,67
Nd 21.7 54.8 27.5 * * 54.8 31.7 40.1 25.6 27.3 28 26 39,2
Sm 4.35 9.07 6.09 * * 9.07 4.37 6.41 5.66 6.15 5.29 5.11 6,88
Eu 0.46 1.46 0.78 * * 1.46 1.03 1.37 0.72 0.72 0.66 0.59 0,68
APPENDIX B
MANUSCRIP
T
ACCEPTED
ACCEPTED MANUSCRIPT
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
Gd 3.76 6.7 4.96 * * 6.7 2.92 5.41 4.69 5.29 3.71 4.24 5,37
Tb 0.62 0.81 0.72 * * 0.81 0.39 0.78 0.77 0.85 0.52 0.69 0,8
Dy 3.67 3.42 3.15 * * 3.42 2.13 4.23 4.13 4.58 2.5 3.85 4,1
Ho 0.69 0.57 0.57 * * 0.57 0.41 0.86 0.76 0.85 0.42 0.73 0,75
Er 2 1.46 1.48 * * 1.46 1.27 2.41 2.2 2.4 1.16 1.98 1,96
Tm 0.31 0.23 0.22 * * 0.23 0.21 0.34 0.34 0.37 0.18 0.28 0,27
Yb 1.91 1.36 1.21 * * 1.36 1.48 2.2 2.25 2.21 1.09 1.76 1,92
Lu 0.3 0.27 0.19 * * 0.27 0.23 0.33 0.31 0.34 0.16 0.26 0,26
*Bellow detection limit; ** Bogotá as origin of the reference system; Plane Gauss Krüger projected coordinates.
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