At Storm Peak, the lower flow fossiliferous inter-beds had an annual sedimentation rate of 0.66 to1.45 millimeters; upper flow fossiliferous interbeds(273 meters above the lower flow interbed) had arate of 0.57 to 1.57 millimeters. These figures, strik-ingly close, suggest no change in sedimentation con-ditions across the time interval separating the twointerbeds. This parallels analytical data developedthus far that indicate persistence of the basic eco-system structure as well.

Work continues on the Newcastle Coal measures(New South Wales) collection. Recently completedis the faunal-paleoecological study of nonmarinearthropods of the Tasmanian Triassic for whichProfessor Max Banks, University of Tasmania, willprovide the stratigraphic context. Data suggest cor-relation of conchostracan-bearing beds of the Knock-lofty formation (Triassic) with those of the Aus-tralian mainland, and the Indian Triassic (Tasch, inpreparation).

References

Taseh, P. 1973. Jurassic beetle from southern Victoria Land,Antarctica. Journal of Paleontology, 47(3) 509-591,fig. 1.

Tasch, P. 1974. Ancient precursors of modern antarcticfreshwater ecosystems. SCAR/IUBS third symposium onantarctic biology, 26-30 August 1974. Abstract. Washing-ton, D.C., National Academy of Sciences. p. 64.

Tasch, P. In preparation. Nonrriarine arthropod fauna ofthe Tasmanian Triassic (with a section on "stratigraphicsetting, by M. R. Banks).

Figure 1 (opposite center). Beetle elytra. (a)Length, 3.1 millimeters; Carapace Nunatak, Taschstation 1, bed lb (composite photo). (b) Carbon-ized specimen; length, 3.5 millimeters; idem,Tasch station 0 (±7 meters south of station 1).Figure 2 (opposite right). Eumalacostracan syn-card; abdomen with three somites and fan-shapeduropod (arrow); Carapace Nunatak, Tasch station2, bed 1; height of carbonized fragment, 2.55centimeters (composite photo). Figure 3 (oppositeleft). Notostracan. (a) Carbonized abdomen withfo.Ir spine-bearing body rings, displaced telsonanJ caudal filaments (arrow); note lack of supra-angll plate (Trops sp.); Carapace Nunatak, Taschstation 2, bed 1; width of body ring, 3.0 milli-mele rs (composite photo). (b) Detail of caudalflldments from same specimen; length, 1.05 milli-

meters.

Sptember-October 1974

Zirconium concentrations and initialstrontium-87/strontium-86 ratios,

Kirkpatrick basalt, Storm Peak,Queen Alexandra Range

G. FAURE, L. B. OWEN, J . R. BOWMAN,and D. H. ELLIOT

Department of Geology and MineralogyInstitute of Polar StudiesThe Ohio State University

Columbus, Ohio 43210The concentrations of zirconium in basalt from

Storm Peak, Queen Alexandra Range, TransantarcticMountains, exhibit systematic stratigraphic variationsand correlate positively with initial strontium-87/strontium-86 ratios. This correlation is incompatiblewith magmatic differentiation in a closed system andis indicative of contamination of a parent basaltmagma with granitic material having a high zir-conium concentration and a high strontium-87/strontium-86 ratio.

Storm Peak (84°35'S. 163°55'E.) is capped by 12basalt flows with a total thickness of about 525 meters.The stratigraphy and petrography of these flows aredescribed by Elliot (1970, 1972), and Faure et al.(1972, in press) discuss their petrogenesis based onchemical and strontium isotope data. We now reportconcentrations of zirconium determined by x-rayfluorescence spectrometry of 18 samples. A calibra-tion was obtained by means of U.S. Geological Sur-vey rock standards (Flanagan, 1973) and included acorrection for interference of strontium-K P radiationwith zirconium-K a radiation. The average differencebetween 10 duplicate determinations is about 2 per-cent and the accuracy of the zirconium concentrationsis believed to be better than 10 percent. The resultsare shown in the table.

The zirconium concentrations range from 81 to 220parts per million and have a mean of 174 ± 35 partsper million (one standard deviation for 18 samples).This value is high when compared to the data com-piled by Prinz (1967), who found an arithmeticmean value of 111 parts per million and a range from20 to 335 parts per million in 146 analyses of quartz-normative tholeiites.

Part A of the figure is a schematic plot of the aver-age zirconium concentrations of the flows versus theflow number, counting from the bottom up. Thereare three sharp discontinuities that separate four setsof flows exactly as shown earlier by Faure et at. (inpress) on the basis of all of the major oxides andstrontium concentrations. These sets of flows are iden-tified by Roman numerals and are interpreted as epi-sodes of volcanic and petrogenetic processes.

Part B of the figure is a plot of the initial stron-tium-87/strontium-86 ratios of the samples (corrected

239

IV A

.\.\.

III

II

I I

12

11

10

9

8

N

6B

fif

4

3

2

1

87 Sr(86^

Sr0

0.713

0.712

0.711

0.710

0.709

0.708

'27.17

B--/.J

cxl

X°/x .vHX

o- 0 Set IV

27.41

• Set IIIxSet IIOSet I

80120160200Zr, ppm

87Sr

(86Sr0

0.716

0.712

ao120160200Zr, ppm

GRAN ITICCOMPONENT

BASALT FLOWS

0.708

/ BASALT

0.704

[

COMPONENT

IIII

for decay of rubidium-87 since formation of theserocks 170 million years ago) versus their zirconiumconcentrations (Faure et al., in press). A strong posi-tive correlation between these parameters is apparent.Such a correlation is incompatible with differentationof magma in a closed system because the isotopes ofstrontium are not measurably fractionated by such aprocess. The positive correlation shown in part B ofthe figure suggests contamination of a basaltic magmawith material having a high strontium-87/strontium-86ratio and a high zirconium concentration. Faure

240

A. Schematic plot of zir-conium concentrations of thebasalt flows on Storm Peaknumbered from the bottomup. B. Positive correlationbetween the initial strontium-87/strontium-86 ratios of individual samples and theirzirconium concentrations. C.Mixing hyperbola for the

flows in sets II and Ill.

et al. (in press) show that this contaminant ap-proached an iron-rich granitic rock in composition.

If the strontium-87/strontium-86 ratio of the basaltcomponent was 0.706, as suggested by Faure et al.(in press), the zirconium concentration of the baaltcomponent was approximately 102 parts per milli 4m;this is in excellent agreement with the average valuereported by Prinz (1967). The zirconium concenta-tion of the contaminant appears to have been abut330 parts per million, assuming that its strontium-87/strontium-86 ratio was 0.720.

ANTARCTIC JOURNAL

0100200300400500Zr, ppm

Geological surveys of Marie Byrd Landand the central Queen Maud Range

This research was supported by National ScienceFoundation grant ov-41037X.

Initial strontium 87/86 ratios and zirconium concentrations,Kirkpatrick basalt, Storm Peak, Queen Alexandra Range.

(81Sr),

87Sr ZrSample Flow Set - (ppm)

27.00 1I0.709481.027.1 2II0.7122193.227.2 2II0.7123196.927.3 2II0.7120197.427.4 2II0.7112190.5Average flow #2 II0.7119194.527.51 3II0.7112*179.527.13 4II0.7115*177.527.56 5II0.7113177.527.17 6III0.7144188.127.18 6III0.7122190.9Average flow #6 III0.7133189.527.24 7III0.7129195.827.25 7III0.7120192.0Average flow #7 III0.7125193.927.64 8III0.7105170.127.67 9III0.7108150.527.28 10III0.7103121.527.29 10III0.7095114.4Average flow #10 III0.7099118.027.36 11IV0.7117199.927.41 12IV0.7095219.7

* Adjusted according to evidence presented by Faure et al.(in press).

References

Elliot, D. H. 1970. Jurassic tholeiitic basalts of the centralTransantarctic Mountains, Antarctica. In: Second Co-lumbia River Basalt Symposium, Proceedings (Gilmour,E. H., and D. Stradling, editors): 301-325. Cheney, East-ern Washington State College Press.

Elliot, D. H. 1972. Major oxide chemistry of the Kirkpatrickbasalt, central Transantarctic Mountains. In: AntarcticGeology and Geophysics (Adie, R. J . , editor): 413-418.Oslo, Universitetsforlaget.

Faure, G., R. L. Hill, L. M. Jones, and D. H. Elliot. 1972.Isotope composition of strontium and silica content ofMesozoic basalt and dolerite from Antarctica. In: Ant-arctic Geology and Geophysics (Adie, R. J . , editor)617-624. Oslo, Universitetsforl age t.

Faure, G., J . R. Bowman, D. H. Elliot, and L. M. Jones.In press. Strontium isotope composition and petrogenesisof the Kirkpatrick basalt, Queen Alexandra Range, Ant-arctica. Contributions to Mineralogy and Petrology.

Flanagan, F. J . 1973. 1972 values for international geo-chemical reference samples. Geochemica et CosmochemicaActa, 37: 1189-1200.

Prinz, M. 1967. Geochemistry of basaltic rocks: trace ele-ments. In: Basalts: The Poldervaart Treatise on Rocks ofBasaltic Composition (Hess, H. H., and A. Poldervaart,editors), I: 271-324. Interscience.

F. ALTON WADEThe Museum

Texas Tech UniversityLubbock, Texas 79409

Marie Byrd Land. Geologic maps of three quad-rangles in Marie Byrd Land have been completed andsubmitted to the U.S. Geological Survey (usGs) forpublication under an arrangement with the NationalScience Foundation. Base maps used were from the1:250,000 Reconnaissance Series, Antarctica, pub-lished by the USGS. The quadrangles are AlexandraMountains, Guest Peninsula, and Boyd Glacier; afourth quadrangle, Gutenko Nunataks, is in prepara-tion.

Detailed studies of the plutons intruded in westernMarie Byrd Land in Middle Paleozoic and Cretaceousare in progress. Granodiorites generally characterizethe older plutons and granites, and leucogranites theyounger. Basic plutons and flows associated with eitherof the two events are relatively few in number andtheir total volume is relatively small.

The oldest known rocks in the area are a thicksequence of metasediments and metavolcanics thataccumulated in a marginal eugeosyncline in the LatePrecambrian to Early Paleozoic (Lopatin andOrlenko, 1972). Subsequent deformations during twoor more orogenies, each followed by a long intervalof erosion, have partially obliterated the record of thesequence of events. An attempt, however, is beingmade to reconstruct the early history of this part ofWest Antarctica through a detailed study of speci-mens from many outcrops. To assist in this task,zonation by means of acritarch assemblages will beattempted. Acritarchs and algal remains have beenreported in a few specimens from this area (Iltchenko,1972).

Queen Maud Range. The basement complex in theShackleton Glacier area of the Queen Maud Range,Transantarctic Mountains, has been restudied in de-tail. Conclusions have been reached that are some-what different from those previously reported (Wadeet al., 1965). A final report on this study is in prepara-tion. A brief summary of the salient conclusions ispresented here.

Two sequences of metasediments are exposed in thearea. On either side of Ramsey Glacier a sequence ofeugeosynclinal fine- to medium-grained arkosic sand-stones and siltstones crop out. The strike of the bed-ding planes is roughly north-south and dips are nearvertical. Sills of andesite intrude the sediments. Meta-morphism has produced biotite facies metasediments.Microfabric studies revealed two deformation events.

September-October 1974 241