CALIFORNIA GEOLOGICAL SURVEY JOHN G. PARRISH, Ph.D., STATE GEOLOGIST CGS SPECIAL REPORT 217, PLATE 24 GEOLOGIC COMPILATION OF QUATERNARY SURFICIAL DEPOSITS IN SOUTHERN CALIFORNIA PALM SPRINGS 30' x 60' QUADRANGLE STATE OF CALIFORNIA - EDMUND G. BROWN, JR., GOVERNOR NATURAL RESOURCES AGENCY - JOHN LAIRD, SECRETARY DEPARTMENT OF CONSERVATION - MARK NECHODOM, DIRECTOR MAP UNITS Projection: Universal Transverse Mercator, Zone 11 North, North American Datum of 1983. Topographic contours derived from USGS 1/3 arc-second National Elevation Dataset (NED). Shaded topographic relief derived from USGS 1 arc-second NED. Base map of hydrography from National Hydrography Dataset Plus (NHDPlus) and California Department of Fish and Game. Base map of geographic names from USGS Geographic Names Information System (GNIS). MAP LOCATION CALIF. INDEX TO USGS 7.5' QUADRANGLES Artificial Fill - deposits of fill resulting from human construction, mining, or quarrying activities; includes engineered fill for buildings, roads, dams, airport runways, harbor facilities, and waste landfills af Late Holocene (Surficial Deposits) Holocene to Late Pleistocene (Surficial Deposits) Late to Middle Pleistocene (Surficial Deposits) Middle to Early Pleistocene (Surficial Deposits) Quaternary (Bedrock) Tertiary (Bedrock) Mesozoic and Older (Bedrock) Young Alluvial Valley Deposits - unconsolidated to slightly consolidated, undissected to slightly dissected clay, silt, sand, and gravel along stream valleys and alluvial flats of larger rivers ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Qya Old Alluvial Valley Deposits - slightly to moderately consolidated, moderately dissected clay, silt, sand, and gravel along stream valleys and alluvial flats of larger rivers Qoa Very Old Alluvial Fan Deposits - moderately to well-consolidated, highly dissected boulder, cobble, gravel, sand, and silt deposits issued from a confined valley or canyon Qvof Very Old Alluvial Valley Deposits - moderately to well-consolidated, highly dissected clay, silt, sand, and gravel along stream valleys and alluvial flats of larger rivers; generally uplifted and deformed Qvoa Coarse-grained Tertiary age formations - primarily sandstone and conglomerate Tss Fine-grained Tertiary age formations - includes fine-grained sandstone, siltstone, mudstone, shale, siliceous and calcareous sediments Tsh Tertiary age formations of volcanic origin Tv Alluvial Valley Deposits - unconsolidated clay, silt, sand, and gravel recently deposited parallel to localized stream valleys and/or spread more regionally onto alluvial flats of larger river valleys; sandy sediment generally more dominant than gravelly sediment Qa Landslide Deposits - may include debris flows and older landslides of various earth material and movement types; unconsolidated to moderately well-consolidated Qls Granitic and other intrusive crystalline rocks of all ages gr Undifferentiated Surficial Deposits - includes colluvium, slope wash, talus deposits, and other surface deposits of all ages; generally unconsolidated but locally may contain consolidated layers Qsu M M F F F F F F M F M F F M F M F M F F M F F K K F F F F F F M M M M M F M F M F M F M M M F M F M F F M M F M F F M M F F M M F F M F M F M F F M M M M F M M M M M M M M M M M F F F F F M M M M M F M M F M F M F M F F F M F M A A A A A A A A A A A A A A A A A A A A A A A A A A A A A W A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A Hemet Indio Coachella Beaumont Banning San Jacinto La Quinta Rancho Mirage Palm Springs Cathedral City Desert Hot Springs Palm Desert Anc i en t L a k e C ahui l l a S h o r e li n e San Gorgonio River 1500 1250 1000 750 500 250 2250 2000 0 0 2000 750 500 1750 1500 1250 1500 2500 2250 1750 1500 2500 500 750 1250 750 2250 2000 0 0 250 500 2250 1500 1250 1500 2000 1750 1500 750 0 750 1000 2500 1500 2000 500 0 0 2750 2500 750 1750 1500 1250 1500 2250 1500 1500 750 750 750 1500 250 1500 750 750 500 750 750 500 1000 1000 1000 1250 500 0 0 0 1750 1500 500 1500 1750 1250 1250 1000 1250 1250 750 1000 500 500 1500 250 1250 750 1250 750 1250 1500 750 750 1750 1500 500 750 1500 1500 750 1500 1250 500 750 750 750 750 750 1500 1500 1250 250 500 1500 250 500 1250 1000 1250 1500 0 0 0 750 1000 1250 0 0 1000 1250 1500 1250 500 1500 1250 1500 1250 500 1000 1250 1250 1500 1500 1000 0 250 1250 1500 500 500 500 1000 3000 1750 1250 1750 gr gr gr gr gr gr gr gr gr gr gr gr gr gr gr gr gr gr gr gr pKm pKm pKm pKm pKm pKm pKm pKm pKm pKm pKm pKm pKm pKm pKm pKm pKm pKm pKm pKm Qe Qe Qe Qe Qe Qe Qe Qe Qf Qf Qf Qf Qf Qf Qls Qls Qls Qls Qls Qls Qls Qls Qls Qls Qls Qoa Qoa Qoa Qoa Qoa Qof Qof Qof Qof Qof Qof Qof Qof Qof Qof Qof Qof Qss Qss Qss Qss Qss Qss Qss Qsu Qvof Qsu Qsu Qvof Qw Qya Qya Qya Qya Qya Qya Qya Qya Qye Qye Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qyf Qya Qya Qya Qya Qya Qya Qya Tsh Tsh Tsh Qss Tss Tss gr gr gr Qya Qyf Qyf gr gr gr gr gr pKm pKm pKm pKm Qvof Qw Qw Qw Qw Qw Qya Qyf Qyf Tss Tss Tss Qyf Qvof Qoa Qw Qof Qa gr Qya Qw Qvof Qof Tss Qw Qyf Qyf gr Qyf Qls Qw Tss Qyf Qof Qyf Qvof Qyf Qyf Qvof Tss Tss pKm pKm gr Qw Qof gr Qya Qya Tss Tss gr pKm Qya Qss Qyf Qss Qw Qls Qls Qss gr Qof Qvof Qyf Qyf Qf Qyf Qvof Qya pKm pKm gr Qyf Qyf Qyf gr Qa Tss Qss Qw Qyf gr pKm gr Qof Qss gr Qya Qya Qya Qsu Qyf Qw gr Qsu Qsu Qw pKm gr Qyf Ql Qw Qyf pKm Qyf Qyf gr Qw Qyf pKm Qw Qvof Qyf Qof Qss Qw Qvof Qya Qyf Qya Qya Qw Qyf Qyf Qe Qyf Qw Qw Qya Qya Qw Qvof Qyf Qyf Qyf Qyf Qof Qyf Qsu Qyf Qw Qw gr gr gr Qsu Qof Qya Qw gr Qyf Qyf Qw pKm gr Tss Tss Tss Qyf gr Tss pKm Qyf Qyf gr Qyf Qvof Qof Qof Qw Qls Qof Qyf Qye Qyf Qe Qw Qye Qya gr Qw Qya Qyf Qls gr Qyf Qw Qyf Qls Qls gr Qyf Qyf Qya Qls Qyf gr Qof gr pKm pKm pKm Qls Qls Qls Qyf Qyf Qf Qw Qya Qya Qyf Qyf Qya Qw pKm pKm Qya gr pKm Qe Qvof Qe Qvof Qe Qyf Qw Qya Qyf Qe Qf Qyf Qe Qya pKm Qof Qw Qyf gr Qoa Qss Qof pKm Qyf gr Qoa Qoa Tss pKm Qyf Qa pKm gr pKm Qa Tss Qyf Qyf Qya Qya Qyf gr pKm pKm Qya Qyf pKm Tss Qw Qya Qya Qya Qya Qoa Tss Qya gr Qya Qoa Tss pKm Qof gr Qw Qw pKm Qss Qss Tss Tss Qof Qw Tss Qw gr pKm Qof Qof Qof Qw Qvoa Qss Qls Qls Qls Qyf Qf Qyf Qf Qf pKm gr Tsh Qya pKm pKm Qyf Qe Qof Qw Qya Qyf Qe Qya Qe gr pKm Qyf Qw gr gr gr Qvof Qof Qa Tss Tss Qw Qw Qyf Qya Qyf Qya Qyf pKm Qss Qw Qyf Qyf Qss pKm gr Qf Qoa Qyf CASA LOMA FAULT Qyf HOT SPRINGS FAULT CLARK FAULT Qw Qyf Qls Qw gr Qw Qyf Qw Qyf Qyf Qe Qw Qyf Qvof Qof Qof Qvof Qw Qyf gr Qyf Qof Qyf pKm Qof pKm Qof pKm Qof Qyf Qof pKm Qyf pKm Qw Qe gr Qya Qyf Qof Qya Qya gr gr Qof gr Qss Qls Qya Tss pKm pKm Qw Qvof Qyf Tss Qyf Qw Qw pKm gr Qvof Qyf Tss gr Qss SAN JACINTO FAULT ZONE pKm Qsu Qvof Qya Qvof Qls Qye Qe Qya Qye Qof gr gr Qw Qof pKm Qof Qw gr Qyf Qls BUCK RIDGE FAULT COYOTE CREEK FAULT Qyf Qvof Qyf Qyf SAN ANDREAS FAULT BLUE CUT FAULT MISSION CREEK STRAND BANNING STRAND GARNET HILL STRAND Qyf Qw D e vi l C a ny o n Qsu Qw Qw Qyf Qyf Qe Qyf Qyf T h e r m a l C a n y o n Qyf Qvof Qvof Qvof Qyf Qyf Qyf Qyf Qw gr Qsu gr Qw pKm Qyf Qof Qyf Qw Qw Qyf Qyf Qya Qof Qyf Qw Qw gr Qls Qyf gr Qw Qof Qsu Qyf Qyf gr gr gr Qyf Qya Qof Qya Qya Qya Qyf Qf Qss Qss Qof gr gr pKm Qls Qvoa Qya Qya pKm Qw Qya Qya pKm Qof gr Qyf gr pKm Qyf Qw Qls Qyf Qls Qls Qls Qyf Qw Qw Qw Qf Tss Qls Qls SA N G O RG O N IO P AS S F A U L T ZON E Qw Qw Qyf Qw Qof Qvof Qya Qe Qe BEAUMONT PLAIN FAULT ZONE + 10 + 10 + 10 + 10 + 10 þ 243 þ 195 þ 79 þ 111 þ 111 þ 74 þ 74 þ 86 þ 74 þ 74 þ 111 þ 111 þ 111 þ 74 þ 86 þ 111 þ 111 þ 74 þ 62 + 10 + 10 þ 243 þ 79 þ 111 þ 371 þ 243 Whitewater Hill Vandeventer Flat Little Cahuilla Mountain Cahuilla Mountain Tripp Flats Butterfly Peak Chalk Hill Keen Ridge West Ridge Windy Point Bald Mountain Lion Peak Little Pinyon Flat Park Hill Pine Mountain Skunk Cabbage Meadow Suicide Rock Apache Peak Asbestos Mountain Barker Peak Black Hill Black Mountain Desert Angel Hemet Butte McMullen Flat Pine Meadow Oak Flat Ranger Peak Tahquitz Falls Cone Peak Jean Peak Palm View Peak Point Happy Castle Rocks Gold Hill Oak Cliff South Peak One Horse Ridge Cornell Peak Indio Mountain Sheep Mountain Eisenhower Mountain Keys View Martinez Mountain Pinyon Alta Flat Red Mountain Thomas Lost Horse Mountain Rock Point Pyramid Peak Devils Rockpile K Flat San Jacinto Peak Baldy Mountain Toro Peak Pinyon Flat Haystack Mountain Flat Top Mountain Edom Hill Willow Hole Garnet Hill Hidden Falls Spring Crest Murray Hill Marion Ridge Poppet Flat Hurley Flat Mount Edna Davis, Mount Tahquitz Peak McGregor Flat Mesquite Flat Reservoir Butte Sagebrush Flat Table Mountain Lookout Mountain Roundtop Spitler Peak Polly Butte Angelus Hill Indian Mountain Fuller Ridge Marion Mountain Cabazon Peak Mountain Kitching Peak San Jacinto Valley Garner Valley Idyllwild South Ridge Coachella Valley Indio Hills Mecca Hills Little San Bernardino Mountains Hexie Mountains Whitewater Cove Salton Sea Fan Hill Queen Valley Ryan Mountain San Jacinto Mountains Cherry Valley Garnet Ridge Martinez Mountain Landslide Santa Rosa Mountain Toro Canyon F a r g o C a n y on L it t l e F a r go C a n y on Indio Canyon Berdoo Canyon F a n H ill C a n yo n P u s h w alla C any on E a s t D e c e p t io n C a n y o n W e s t D e c e p t i o n C a n y o n Malapai Hill Lost Horse Valley E as t W i d e C a n y o n We s t W i d e C a n yo n L o n g C a n y o n Devers Hill T a hqu i tz Ca n y o n A n dr e as C a nyon M u rray Cany on Palm Canyon Anza Valley Oak Mountain Rouse Ridge Blackburn Ridge Banning Bench San Bernardino Mountains Banning Canyon M i l la r d Cany o n C h i n o C an yo n Anza Pleasant Valley Santa Rosa Mountains Martinez Canyon B a u t i s t a W a s h B r o w n C r e e k Po t r e r o C r e e k G u a d a l u p e C r e e k C a t C r e e k C a h u i l l a C r e e k B e a r C r e e k Q u a i l W a s h T uc a l o t a C r e e k Sm i t h C r e e k M a r i o n C r e e k A z a l e a C r e e k A l k a l i W a s h C a h u i l l a C r e e k T w i n P i n e s C r ee k Ho r s e t hi e f C re e k M i s s i o n C r e e k G o l d S h o t C r e e k E l d e r C r e e k E b b e n s C r e e k C a r r i zo C r e e k S h e e p C r eek Co y o t e C r ee k Lake Hemet B a i sl e y C r e e k M a r t i n e z C re e k M o n t g o m e ry C r e e k H o r se Cree k Fr ie d L i v e r Wa s h Whitewater River M o r o n go W a s h Sn o w C r ee k J e n s e n C r e e k G r a p e v in e C r ee k G a rn e t Q u e e n C r e e k S a n J ac i n t o R i v e r Whitewater River S m i t h C r e e k Qw Alluvial Wash Deposits - unconsolidated sandy and gravelly sediment deposited in recently active channels of streams and rivers; may contain loose to moderately loose sand and silty sand Coarse-grained formations of Pleistocene age and younger - primarily sandstone and conglomerate Qss Cretaceous and pre-Cretaceous metamorphic formations of sedimentary and volcanic origin pKm Alluvial Fan Deposits - unconsolidated boulders, cobbles, gravel, sand, and silt recently deposited where a river or stream issues from a confined valley or canyon; sediment typically deposited in a fan-shaped cone; gravelly sediment generally more dominant than sandy sediment Qf Young Alluvial Fan Deposits - unconsolidated to slightly consolidated, undissected to slightly dissected boulder, cobble, gravel, sand, and silt deposits issued from a confined valley or canyon Qyf Old Alluvial Fan Deposits - slightly to moderately consolidated, moderately dissected boulder, cobble, gravel, sand, and silt deposits issued from a confined valley or canyon Qof (SANTA ANA) SCALE 1:100 000 CONTOUR INTERVAL 50 METERS NATIONAL GEODETIC VERTICAL DATUM OF 1929 5000 0 5000 10000 15000 20000 25000 30000 35000 40000 45000 50000 FEET 5 0 5 2.5 MILES 0 5000 5 0 5 10 2.5 KILOMETERS METERS 5000 10000 www.conservation.ca.gov/cgs © The Department of Conservation makes no warranties as to the suitability of this product for any particular purpose. Copyright 2012 by the California Department of Conservation. All rights reserved. No part of this publication may be reproduced without written consent of the California Geological Survey. Information on this map is not sufficient to serve as a substitute for the geologic and geotechnical site investigations required under Chapters 7.5 and 7.8 of Division 2 of the California Public Resources Code. [For geologic line symbols: lines are solid where location is accurate, long-dashed where location is approximate, short-dashed where location is inferred, dotted where location is concealed. Queries added where identity or existence may be questionable.] Folds -- Showing direction of plunge where appropriate SYMBOL EXPLANATION County boundary Road Stream Anticline F Syncline M Fault -- Includes strike-slip, normal, reverse, oblique, and unspecified slip Contact ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Qt * * Boundaries of Quaternary units are gradational and time transgressive in a regional sense. CORRELATION OF MAP UNITS Late Holocene Holocene to Late Pleistocene Late to Middle Pleistocene Middle to Early Pleistocene Quaternary (Bedrock) Tertiary (Bedrock) Artificial Fill Undiff. Surficial Deposits Landslide Deposits Alluvial Wash Deposits Alluvial Fan Deposits Alluvial Valley Deposits Lacustrine, Playa, and Estuarine Deposits Eolian and Dune Deposits Cretaceous and Pre-Cretaceous Metamorphic (sedimentary and volcanic) Granitic Rocks (all ages) Coarse- grained Volcanic Alluvial Deposits ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Qe ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Ql Qa Qf Qls Qsu af ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Qye ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! Qyl ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Qya Qyf Qvof Qoa Qof Tss pKm gr Quaternary Surficial Deposits Tv Qw Mesozoic and Older (Bedrock) ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Qyt Qvoa Qss Tsh Terrace Deposits Fine- grained Young Terrace Deposits - unconsolidated to slightly consolidated, undissected to slightly dissected marine and stream terrace deposits !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Qyt Young Lacustrine, Playa, and Estuarine (Paralic) Deposits - unconsolidated to slightly consolidated, undissected to slightly dissected fine-grained sand, silt, mud and clay from lake, playa, and estuarine deposits of various types ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Qyl Young Eolian and Dune Deposits - unconsolidated to slightly consolidated, undissected to slightly dissected wind-blown sands ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! Qye Terrace Deposits - includes marine and stream terrace deposits; marine deposits include slightly to moderately consolidated and bedded gravel and conglomerate, sand and sandstone, and silt and siltstone; river terrace deposits consist of unconsolidated thin- to thick-bedded gravel ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Qt Eolian and Dune Deposits - unconsolidated, generally well-sorted wind-blown sand; may occur as dune forms or sheet sand ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Qe Lacustrine, Playa, and Estuarine (Paralic) Deposits - mostly unconsolidated fine-grained sand, silt, mud, and clay from fresh water (lacustrine) lakes, saline (playa) dry lakes that are periodically flooded, and estuaries; deposits may contain salt and other evaporites ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Ql (EAGLE MOUNTAINS) (SAN BERNARDINO) (OCEANSIDE) (BIG BEAR LAKE) (SHEEP HOLE MOUNTAINS) (SALTON SEA) (BORREGO VALLEY) 116°5' 116°5' 116°10' 116°10' 116°15' 116°15' 117° 117° 116°20' 116°20' 116°55' 116°55' 116°25' 116°25' 116°50' 116°50' 116°30' 116°30' 116°45' 116°45' 116°35' 116°35' 116°40' 116°40' 33°55' 33°55' 33°50' 33°50' 33°45' 33°45' 33°40' 33°40' 33°35' 33°35' 34° 33°30' 34° 116° 116° 33°30' isolated valleys of the Peninsular Ranges; and in the Coachella Valley, a deep sedimentary trough. These alluvial basins are bordered by tectonically active mountains that are experiencing deformation such as uplift, folding, and faulting in response to the active west-north west trending San Andreas and San Jacinto Fault systems, which both transect the quadrangle diagonally. Within the Peninsular Ranges, the San Jacinto and Santa Rosa Mountains, along with numerous lesser ridges and peaks, have formed due to uplift in response to movement on the San Andreas and San Jacinto Faults. In the map area the San Jacinto Fault Zone bisects the Peninsular Ranges and is composed of several strands that bend or step laterally along their trend. Quaternary faulting has enhanced the development of consequent linear drainages that drain to alluvial valleys situated on or adjacent to these fault trends. Quaternary age alluvial fans and alluvial valley deposits form on the margins of several of these valleys, including the San Jacinto, Anza and Garner Valleys. In the mountainous regions of the province, alluvial wash, terrace, and older alluvial deposits are confined within narrow canyons with very few broad alluvial valleys. Along the northern margins of the San Jacinto Mountains, steep Holocene age debris flow fans emanate from Jenson, and Snow Creek, and Chino, Tahquitz, Andreas and Murray Canyons. Very coarse boulder fields, boulder lined levees, debris tracts and terminal snouts dominate the surface expression of these fans. In slight contrast, the northern flank of the Santa Rosa Mountains is notched with deeply embayed canyons (from the eastern edge of Palm Canyon to La Quinta) such as Cathedral and Magnesia Spring Canyons, and Dead Indian, Sheep, and Bear Creeks. Farther east along the Santa Rosa range front, from Devil Canyon to the map boundary, drainages become less embayed with several debris fans emanating from smaller drainages between Toro and Martinez Canyons. Historic debris laden floods, such as occurred in Magnesia Spring Canyon in 1979 (NRC, 1996) have occurred on the alluvial fans emanating from the Santa Rosa Mountains. Relatively fresh indictors of scour and deposition are present on latest Holocene age alluvial fan surfaces in this area. Within the Transverse Ranges, thick sequences of Quaternary-age alluvial deposits are extensive along the base of the San Bernardino and Little San Bernardino Mountains. Along the southern San Bernardino Mountains alluvium has formed in drainages and as alluvial fans issuing from Millard Canyon, Banning Canyon, and smaller catchments. These deposits form moderately sloping alluvial fans that terminate on the south side of the valley. Quaternary alluvial fan deposits of Pleistocene and Early Holocene age have been uplifted on the upper plate of the San Gorgonio Pass Fault Zone (Treiman and others, 2012) and are removed from the modern drainage system. These older deposits are recognizable as terrace landforms, such as the Banning Bench and at Whitewater Hill near the town of White Water. Late Holocene age alluvial fans and washes in this region exhibit bar and swale topography suggesting recent activity, but rapidly develop a veneer of eolian sediment. Holocene age debris flow deposits are strongly expressed on alluvial fans along the mountain front where smaller catchments, generally < 1.2 square miles (3 square kilometers) in area exhibit rapid changes in relief from the fan apex to crest. Both historic debris laden floods and debris flows occur locally, as evident from the presence of boulder fields, and boulder lined levees located near the fan apices. Because the San Andreas Fault branches near Indio into three strands (Treiman and others, 2012) that broaden toward the west, a complex series of active strike slip and reverse faults disrupt the horizontal and vertical continuity of Quaternary age alluvial deposits in the San Bernardino Mountains and attendant alluvial fans. Numerous canyons drain the eastern most part of the San Bernardino Mountains and from the crest of the Little San Bernardino Mountains. Several of these canyons are fault controlled and through-going, penetrating greater than 10 miles (16 kilometers) into the core of the mountains (Powell and Matti, 2006). A steep topographic escarpment runs along the south side of the range where these canyons debouch Quaternary age alluvial fan and wash deposits on the piedmont plain. These drainages are Long, West and East Wide, West and East Deception, Fan Hill, Pushwalla, Berdoo, Little Fargo, Fargo and Thermal Canyons. The Mission Creek, Banning, and Garnet Hill strands of the San Andreas Fault disrupt this piedmont plain south of the Little San Bernardino Mountains by faulting and folding Tertiary and Quaternary alluvial fan deposits. This tectonic deformation is expressed as the Indio and Mecca Hills, which have This map of Quaternary surficial deposits of the Palm Springs 30’ x 60’ quadrangle was created by the California Geological Survey (CGS ) for the Department of Water Resources (DWR ) to assist in identifying where flooding and deposition of sediment occurred in the geologically recent past. The focus of this project is on Quaternary (Q) surficial deposits (less than 1.8 million years) on alluvial fans, floodplains, and in basins where such deposits are subject to a number of geologic hazards including flooding, amplification of seismic shaking, liquefaction, and collapsible soils. In general, areas of most recent deposition during Late Holocene time (within the last 500 years) have a greater potential to be areas of future flooding and deposition than those underlain by older surficial deposits. Project Overview The Palm Springs 30’ x 60’ quadrangle represents one of several 100,000 scale quadrangles included in the detailed Geographic Information System (GIS ) based geologic data set compiled by CGS from recent high resolution geologic mapping available for southern California. The GIS database merges more than 2100 geologic units from source maps published primarily by the U.S. Geological Survey (USGS) and by CGS (Source GIS Database) into a common format that depicts 40 derivative categories of surficial deposits and bedrock for the entire area (Derivative GIS Database). Published source geologic mapping at the 100,000 scale was not available for the Palm Springs quadrangle, therefore CGS relied on in-progress mapping by the USGS (Matti, 2012). CGS used the derivative map units as a basis for interpreting and mapping in areas of incomplete or absent data, as well as in assigning attributes based on the 40 derivative categories of surficial deposits and bedrock where source data made this feasible. Where incomplete bedrock data existed in the digital data, existing published references were used to assign rock types to the data set. Significant simplification of the in-progress Matti (2012) data was conducted in order to display the derivative map units. Quaternary surficial deposits are divided into 28 categories modified from the methodology of Matti and Cossette (2007), the Southern California Areal Mapping Project (SCAMP, 2000), and the USGS and CGS (2000). While specific variations in age and physical properties exist within each unit, CGS retained the basic premise of Matti and Cossette (2007) that surficial deposits within each of the Quaternary map units formed during a particular range of geologic time, have a similar origin, and have generally similar physical properties. Within the 28 Quaternary surficial units, progressively older surficial deposits are typically better consolidated and more highly dissected by erosion, have more developed and/or eroded soil profiles with stronger degrees of weathering and surface armoring, and occupy a higher topographic position within alluvial fan and floodplain environments. Geologic bedrock formations are divided into 12 categories, based on age and rock type. The bedrock categories can be used to provide a general understanding of the relative erodibility of the upland materials and the general character of the derived sediments. CGS also rectified inconsistencies along the boundaries of mapped areas to create a seamless Derivative GIS Database with other 30’ x 60’ quadrangles previously compiled under CGS Special Report 217. Correlation of equivalent deposits across the entire southern California project area is represented in the GIS table entitled Correlation of Derivative and Source Geologic Map Units. Palm Springs Quadrangle The Palm Springs quadrangle is situated at the convergence of four geomorphic provinces. The Peninsular Ranges Geomorphic Province occupies the region from Palm Springs and Palm Desert to the southern and western map boundaries, and is punctuated by San Jacinto Peak at an elevation of 10,834 feet (3,302 meters).The Transverse Ranges Geomorphic Province is located in the northwest, north-central, and northeast portion of the quadrangle where the San Bernardino Mountains descend into the San Gorgonio Pass, and the Little San Bernardino Mountains descend into the Coachella Valley. The Mojave Desert Geomorphic Province is located in the northeast region of the quadrangle, and the Colorado Desert Geomorphic Province coincides with the general extent of the Coachella Valley, from the Whitewater River just east of the San Gorgonio Pass, southeast to the Salton Sea. Thick sequences of Quaternary-age alluvial deposits are widespread in the San Gorgonio Pass; within the San Jacinto Valley and smaller MAP EXPLANATION APPROXIMATE MEAN DECLINATION, 2012 ! ! ! ! ! A A TRUE NORTH MAGNETIC NORTH 12 PRELIMINARY GEOLOGIC MAP OF QUATERNARY SURFICIAL DEPOSITS IN SOUTHERN CALIFORNIA PALM SPRINGS 30' X 60' QUADRANGLE December 2012 Jeremy T. Lancaster, CEG, Cheryl A. Hayhurst, PG, and Trinda L. Bedrossian, CEG Compiled from existing sources by Solomon McCrea, Michelle Myers, and Shannon Utley Digital preparation by A Project for the Department of Water Resources by the California Geological Survey DIGITAL GEOLOGIC DATA FILE USED IN GIS COMPILATION OF QUATERNARY UNITS Bryant, W.A. (compiler), 2005, Digital database of Quaternary and younger faults from the Fault Activity Map of California, version 2.0: California Geological Survey, data amended by revisions in progress, 5/5/11. Matti, J.C., 2012, Preliminary geologic mapping in the Palm Springs 30’ x 60’ quadrangle, California: Unpublished, in progress, digital data provided by U.S. Geological Survey to California Geological Survey, versions dated 5/26/2012, 8/7/2012, and 9/10/2012, scale 1:100,000. Morton, D.M., and Kennedy, M.P., 2005, Preliminary geologic map of the Sage 7.5’ quadrangle, Riverside County, California: U.S. Geological Survey, Open-File Report 2005-1285, scale 1:24,000, Morton, D.M., and Matti, J.C., 2005, Preliminary geologic map of the Hemet 7.5’ quadrangle, Riverside County, California: U.S. Geological Survey, Open-File Report 04-1455, scale 1:24,000: U.S. Geological Survey and California Geological Survey, 2011, Quaternary fault and fold database for the nation, California Section. IMAGERY USED National Center for Airborne Laser Mapping (NCALM), 2005, B4 Project- Southern San Andreas and San Jacinto faults. http://opentopo.sdsc.edu/ U.S. Department of Agriculture, 1953, Aerial photographs (designated as AXM; multiple flight lines and frames), black and white, vertical, scale 1:24,400. U.S. Department of Agriculture, Farm Service Agency-Aerial Photography Field Office, National Agriculture Imagery Program (NAIP), 2005a, 1-meter resolution. U.S. Department of Agriculture, Farm Service Agency-Aerial Photography Field Office, National Agriculture Imagery Program (NAIP), 2005b, color infrared, 1-meter resolution. U.S. Department of Agriculture, Farm Service Agency-Aerial Photography Field Office, National Agriculture Imagery Program (NAIP), 2009a, 1-meter resolution. U.S. Department of Agriculture, Farm Service Agency-Aerial Photography Field Office, National Agriculture Imagery Program (NAIP), 2009b, color infrared, 1-meter resolution. REFERENCES USED IN PREPARING LEGENDS AND MAPS FOR QUATERNARY UNITS Matti, J. C., and Cossette, P.M., 2007, Classification of surficial materials, Inland Empire Region, southern California: conceptual and operational framework: U.S. Geological Survey, Open-File Report. Southern California Areal Mapping Project (SCAMP), 2000, A proposed classification for surficial geologic materials in southern California, version 1.0. REFERENCES USED IN PREPARING MAP (SEE INDEX FOR OTHER REFERENCES) Alluvial Fan Task Force (AFTF), 2010, AFTF study area flood history: California State University, San Bernardino- Water Resources Institute, 72p. Calzia, J.P., 1988a, Mineral resource potential map of the Pyramid Peak Roadless Area, Riverside County, California:U.S. Geological Survey, Miscellaneous Field Studies, Map 1999, scale 1:62,500. Calzia, J.P., Madden-McGuire, D.J., Oliver, H.W., 1988b, Mineral resources of the Santa Rosa Mountains Wilderness Study Area, Riverside County, California: U.S. Geological Survey, Bulletin 1710D. Coachella Valley Water District (CVWD), 1978, Coachella Valley’s golden years. Dibblee, T.W., Jr., and Minch, J.A., 2003a, Geologic map of the Beaumont quadrangle, Riverside County, California: Dibblee Geological Foundation, Map DF-114, scale 1:24,000. Dibblee, T.W., Jr., and Minch, J.A., 2003b, Geologic map of the Palm Springs quadrangle, Riverside County, California: Dibblee Geological Foundation, Map DF-123, scale 1:24,000. Dibblee, T.W., Jr., and Minch, J.A., 2003c, Geologic map of the San Jacinto quadrangle, Riverside County, California: Dibblee Geological Foundation, Map DF-116, scale 1:24,000. Dibblee, T.W., Jr., and Minch, J.A., 2004a, Geologic map of the Cabazon quadrangle, Riverside County, California: Dibblee Geological Foundation, Map DF-119, scale 1:24,000. Dibblee, T.W., Jr., and Minch, J.A., 2004b, Geologic map of the Lake Fulmor quadrangle, Riverside County, California: Dibblee Geological Foundation, Map DF-122, scale 1:24,000 Dibblee, T.W., Jr., and Minch, J.A., 2004c, Geologic map of the Whitewater quadrangle, Riverside County, California: Dibblee Geological Foundation, Map DF-120, scale 1:24,000. Dibblee, T.W., Jr., and Minch, J.A., 2007, Geologic map of the San Jacinto Peak quadrangle, Riverside County, California: Dibblee Geological Foundation, Map DF-370, scale 1:24,000 Dibblee, T.W., Jr., and Minch, J.A., 2008a, Geologic map of the Palm Desert and Coachella 15 minute quadrangles, Riverside County, California: Dibblee Geological Foundation, Map DF-373, scale 1:62,500. Dibblee, T.W., Jr., and Minch, J.A., 2008b, Geologic map of the Thousand Palms and Lost Horse Mountain 15 minute quadrangles, Riverside County, California: Dibblee Geological Foundation, Map DF-372, scale 1:62,500. Dibblee, T.W., Jr., and Minch, J.A., 2008c, Geologic map of the Hemet and Idyllwild 15 minute quadrangles, Riverside County, California: Dibblee Geological Foundation, Map DF-371, scale 1:62,500. Dibblee, T.W., Jr., and Minch, J.A., 2010, Geologic map of the Desert Hot Springs quadrangle, Riverside County, California: Dibblee Geological Foundation, Map DF-121, scale 1:24,000. MAP REFERENCES been dissected consequent to uplift, or have antecedent drainages connecting to catchments farther north in the Little San Bernardino Mountains. As a result, alluvial fans of Quaternary age also form along the south flank of these hills. The Quaternary-age alluvial deposits of the Mojave Desert in the northeastern portion of the quadrangle have developed in response to uplift and erosion due to the influence of the nearby San Andreas fault. East of the crest of the Little San Bernardino Mountains, a few broad alluvial valleys exist. One example is Pleasant Valley, a fault bound alluvial trough with alluvial fans merging into the valley axis from the north, west and south. In contrast, Queen Valley is a broad gently sloping erosional plain punctuated by more resistant rocks that comprise Ryan Mountain and the Hexie Mountains (Trent, 1998). This gently sloping erosional plain is known as a pediment, where bedrock is deeply weathered, exposed on the surface, or covered by a thin veneer of alluvium (pediment veneer is map unit Qsu). The Coachella Valley lies within the Colorado Desert and is a deep trough underlain by a thick sequence of Quaternary age alluvial sediment. In the map area this valley drains the San Bernardino, Little San Bernardino and San Jacinto Mountains into the Whitewater River. The Whitewater River is broad system of alluvial washes that scoured a channel up to 50 feet deep in the great flood in 1916 (CVWD, 1978). Along its path to the Salton Sea the river intercepts numerous large drainages from the San Bernardino and Little San Bernardino Mountains to the north, and the Santa Rosa Mountains to the south. While the valley is fringed with alluvial fans, a broad system of braided alluvial washes, and eolian sand dunes and sand sheets make up the valley floor. During the last 2,000 years, the eastern Coachella Valley was filled four times by waters from the Colorado River forming what is known as Ancient Lake Cahuilla (Waters, 1983). The last high stand formed about 500 years before present, and is evident as a strand line of lacustrine deposits at an elevation of 40 feet (12 meters above mean sea level) along the fringes of the valley as far west as Indio. The Coachella Valley has numerous communities that have been built on alluvial fan and valley floodplains. As a result of its unique geomorphic setting, these communities have witnessed intense flooding on alluvial fans, alluvial washes, and on the Whitewater River more than 15 times in the last century (AFTF, 2010). Four events are associated with moisture from Baja California hurricanes making an eastward bend into the southwest U.S. over the Baja Peninsula. In preparing this map of the Palm Springs 30’ x 60’ quadrangle, CGS primarily used in-progress digital data from Matti (2012), Morton and Matti (2005), and Morton and Kennedy (2005) to aid in mapping the Quaternary surficial deposits. In addition to existing geologic map data, geomorphic interpretation of Quaternary surficial deposits was based on geomorphic expression, topographic position, relative dissection, and tonal contrasts. These interpretations were based primarily on observations from topographic contours, digital elevation models (NCALM, 2005) historic aerial photos (USDA, 1953), and USDA NAIP digital imagery (2005a, 2005b, 2009a, 2009b). Quaternary surficial deposits on this map are represented by 18 of the generalized project derivative units. Quaternary faults were compiled using in progress Matti (2012) data, Bryant (2005) and the USGS and CGS (2011) Quaternary fault and fold database. Bedrock geology was compiled from in progress Matti (2012) data, Morton and Matti (2005), Morton and Kennedy (2005), Dibblee and Minch (2003a, 2003b, 2003c, 2004a, 2004b, 2004c, 2007, 2008a, 2008b, 2008c, and 2010), Matti and others (1982, 1983a, 1983b), Morton and others (1980), Calzia (1988a, 1988b), Erskine (1985), Sharp (1965), Hill (1984), Sydnor (1975), and Rogers (1965). Bedrock faults and structure were compiled from the various bedrock sources listed above. Bedrock units identified in the study area are represented on this map by 6 of the 12 project derivative bedrock units (see Map Units and Correlation of Map Units). This map, along with others in the Geologic Compilation of Quaternary Surficial Deposits in Southern California Derivative GIS Database, is regional in nature and should not be used as a substitute for detailed geologic studies in any specific area. It is intended only for rapid identification of areas subject to previous and potential future flooding and other geologic hazards on alluvial fans and floodplains. Erskine, B.G., 1985, Mylonitic deformation and associated low-angle faulting in the Santa Rosa mylonite zone, Southern California: University of California, Berkley: PhD Dissertation. Hill, R.I., 1984, Petrology and petrogenesis of batholitic rocks, San Jacinto Mountains, southern California: California Institute of Technology, PhD Dissertation. Matti, J.C., Cox, B.F., Obi, C.M., Powell, R.E., Hinkle, M.E., and Griscom, A., 1982, Mineral resource potential map of the Whitewater Wilderness Area, Riverside County, California: U.S. Geological Survey, Miscellaneous Field Studies, Map 1478-A, scale 1:24,000. Matti, J.C., Cox, B.F., Powell, R.E., Oliver, H.W., and Kuizon, L., 1983a, Mineral resource potential map of the Cactus Springs Roadless Area, Riverside County, California: U.S. Geological Survey, Miscellaneous Field Studies, Map 1650-A, scale 1:24,000. Matti, J.C., Cox, B.F., Iverson, S.R., 1983b, Mineral resource potential map of the Raywood Flat roadless areas, Riverside and San Bernardino counties, California: U.S. Geological Survey, Miscellaneous Field Studies Map -1563A. Morton, D.M., Matti, J.C., and Cox, B.F., 1980, Geologic map of the San Jacinto Wilderness, Riverside County, California: U.S. Geological Survey, Miscellaneous Field Studies, Map 1159-A, scale 1:62,500. NRC, 1996, Alluvial fan flooding: National Research Council, Committee on Alluvial Fan Flooding, Water Science and Technology Board, Commission on Geosciences, Environment, and Resources, National Academy Press, 172 p. Powell, R.E., and Matti, J.C., 2006, A geologic and geomorphic mapping approach to understanding the kinematic role of faulting in the Little San Bernardino Mountains: in The evolution of the San Andreas Fault system in southern California: Transactions of the American Geophysical Union, abstracts with programs, v.87(52). Rogers, T.H. (compiler), 1965, Geologic map of California, Olaf P. Jenkins edition, Santa Ana sheet: California Division of Mines and Geology, scale 1: 250,000. Sharp, R.V., 1965, Geology of the San Jacinto fault zone in the Peninsular Ranges of southern California: California Institute of Technology, PhD Dissertation. Sydnor, R.H., 1975, Geology of the northeast border of the San Jacinto pluton, Palm Springs, California: University of California Riverside, Master’s Thesis. Treiman, J. A., Matti, J. C., Bryant, W. A., and Kendrick, K. J., 2012, Fault nomenclature for the San Gorgonio Pass region: Southern California Earthquake Center (SCEC) Annual Conference, abstracts with programs, p.143. Trent, D.D., 1998, Geology of the Joshua Tree National Park, San Bernardino and Riverside counties: in California Geology, California Division of Mines and Geology, September/October, p.3-16. Waters, M. R., 1983, Late Holocene lacustrine chronology and archaeology of ancient Lake Cahuilla, California: Quaternary Research v.19, pp.373–387. A Spring W Wet area
