Preliminary Geologic Map available from: http://www.conservation.ca.gov/cgs/rghm/rgm/preliminary_geologic_maps.htm

STATE OF - ARNOLD SCHWARZENEGGER, GOVERNOR CALIFORNIA GEOLOGICAL SURVEY THE RESOURCES AGENCY - MIKE CHRISMAN, SECRETARY FOR RESOURCES Prepared in cooperation with the U.S. Geological Survey, JOHN G. PARRISH, Ph.D., STATE GEOLOGIST DEPARTMENT OF CONSERVATION - BRIDGETT LUTHER, DIRECTOR Areal Mapping Project GEOLOGIC MAP OF THE

119 o22'30" 119 o15'00" o o 70 65 Qls MATILIJA 7.5' QUADRANGLE 55 55 65 34 30'00" 34 30'00" Ku 50 Qw Ku 70 Tj 60 66 Ku 55 60 Tj Qha Qls 62 77 75 70 72 52 65 74 50 74 57 Qls? 55 Qls? Ku 81 77 75 Qha 74 62 48 VENTURA COUNTY, CALIFORNIA: A DIGITAL DATABASE Tj 55 Qls 80 80 73 82 Qha Tj 52 67 Qls 70 Tj 50 Tj 75 54 Qls 55 87 67 71 Qpa 70 65 Qls? 87 VERSION 1.0 Qls Tj Tj 60 70 Tj 65 Qls? 72 Qw 62 By Qha 55 72 Tma 62 60 Tj Tma 62 Qls? Tj 1 1 70 62 65 66 62 Qls Siang S. Tan and Terry A. Jones 50 Tj Qls? 72 65 Qpa 87 Qha Qls 55 Digital Database Tj 85 72 Qls? 80 60 71 Qpa 55 Tcd by 87 88 Tma 2 Qls 75 88 Tma 62 Carlos I. Gutierrez 73 60 75 70 Qls? Tj 86 70 2006 Qls? Qls 50 62 Tcd 87 87 Qls? 66 Qls? 88 60 Qls? 1. California Geological Survey, 888 South Figueroa Street, Suite 475, , CA 90017 70 86 75 Tcd 2. California Geological Survey, 801 K Street, MS 12-32, Sacramento, CA 95814 Qls 67 Qls? 88 82 65 42 Tma 50 67 Qw 35 75 Qls? 50 60 73 74 70 71 Qpa Qls? Qls? 50 65 74 72 70 Qls? Tcw 73 55 72 Tcd Unit Explanation Unit Correlation 65 75 Tcw-sh Qls? 75 Qha 70 55 80 72 Tcd Qls? 70 60 Qw Active wash deposits within major river channels (Holocene) - Composed of 65 70 Tcw 70 Qha Qw Qha Qhf Holocene 80 77 70 Tcw unconsolidated silt, sand and gravel. Tcd 62 75 Tcd 67 65 Qha 75 75 65 Tcw-sh 50 55 Qha Alluvial and colluvial deposits, undivided (Holocene) - Located on the floors of Qpa Qls QUATERNARY 60 52 Qpa 66 50 Tcd 74 valleys; includes active stream deposits in hill slope areas; composed of 72 Tcw Pleistocene Tcw-sh 55 Tcw unconsolidated sandy clay with some gravel. 70 Qpf 72 65 82 75 62 63 75 Alluvial fan deposits (Holocene) - Deposited by streams emanating from mountain Tcw-sh 50 Qhf Qha Qpa canyons onto alluvial valley floors; deposits originate as debris flows, hyper- Tp 73 Qpf 63 65 Tcw Qha Tcw 66 concentrated mudflows, or braided stream flows; composed of moderately to Tcw-sh 73 Tcw-sh Ts Ts poorly sorted, and moderately to poorly bedded, sandy clay with some gravel. Tsq 42 52 65 70 60 Qls Landslide deposits (Holocene to late Pleistocene) - Includes numerous active Tmu 75 63 74 75 63 Ts 60 Qpa landslides, composed of weathered, broken up rocks; extremely susceptible to Qha Tml 50 70 60 65 65 65 Qha renewed landsliding, including their head scarp areas. Miocene 83 62 65 Tcw Ts Qpa Tr CENOZOIC 51 64 64 Qpa Alluvial deposits, undivided (late Pleistocene) - Consists of semi-consolidated silt, 70 72 72 72 55 sand, clay, and gravel. 74 50 Qpa 74 Tv Tcw 70 Qha 70 70 Qls? 75 60 55 TERTIARY 50 50 73 74 Qpa Qpf Alluvial fan deposits (late to middle Pleistocene) - Semi-consolidated poorly sorted 74 70 75 Ts 75 72 75 71 gravel, boulder, sand, silt and clay; often form elevated, slightly tilted, terraces on Oligocene 65 74 55 50 70 hill slope areas. Tcw Ts 72 61 Qpa 70 80 75 Ts 50 47 Qha 42 Tcw-sh 65 Tp Pico Formation, undivided (Pliocene) - Composed of claystone, siltstone, and 50 70 sandstone; locally pebbly; generally susceptible to landsliding. Qpa 35 Qpa 82 74 45 41 Tcd 45 37 40 Eocene Qha Tsq Sisquoc Shale (Pliocene-Miocene) - Silty shale and claystone; generally susceptible Qw Ts 43 45 Qha Tma 40 50 72 60 32 to landsliding. Locally contains siliceous shale similar to the . 44 65 30 30 30 25 40 42 32 35 34 37 55 45 30 75 25 35 Tmu Monterey Formation (middle and late Miocene) - Consists of siliceous and Tj 40 34 Ts diatomaceous shale and some sandstone and limestone; generally susceptible to 40 62 Tml 23 30 Ts 69 landsliding. Tml = lower section, containing punky thin-bedded shale; Tmu = upper Ku 32 30 35 35 55 section, composed of platy brittle siliceous thin-bedded shale. 35 Qha 35 40 55 60 Qpa Qls? 28 Qls? 33 25 32 Tr Rincon Shale (early Miocene) - Composed of shale and siltstone; generally 31 34 Tcw 37 susceptible to landsliding. 30 25 27 30 30 ? ? 55 46 35 24 40 Tv Vaqueros Sandstone (early Miocene) - Consists of sandstone, locally calcareous. 30 35 45 45 Qpa 35 45 27 32 Qpa Sespe Formation (Oligocene) - Composed of sandstone; locally pebbly, siltstone and References 30 23 Ts 30 45 Qpa 35 35 ? 44 claystone; rocks are generally reddish in color. 30 Ts Qpa The bedrock geology is largely modified from Dibblee (1987). Ts 35 Ts 40 35 10 35 15 Tcw Coldwater Sandstone (late Eocene) - Composed of hard arkosic sandstone with Barnard, M., 1979, Geologic map of the Lake Casitas area in Geology of the Lake Casitas area, Ventura County, 32 Qpa Ts 32 siltstone and shale interbeds; locally reddish in color, similar to appearance of California: Field trip guidebook, Coast Geological Society and Pacific Section, American Association of Petroleum 30 Qha 35 Tcw-sh 25 34 Qls Geologists, 1979 Spring field trip, 57 p. 30 32 47 Sespe Formation. Tcw-sh consists predominantly of shale. 30 Qpa Qha Ts California Division of Mines and Geology, 1986, Earthquake Fault Zones, Matilija Quadrangle, Official Map of July 1, 40 Tcd Cozy Dell Shale (late Eocene) - Consists of micaceous shale with arkosic sandstone 30 1986, scale 1:24,000. 29 Ts interbeds; generally susceptible to landsliding. Ts Clark, M.N., 1982, Tectonic geomorphology and neotectonics of the Ojai Valley and upper : University of 35 35 Qpa Matilija Sandstone (middle to late Eocene) - Composed of hard arkosic sandstone Qpa Qha Tma California, Santa Barbara, M.S. thesis, 77 p., 5 plates, scale 1:24,000. 25 27 Qpa Ts 35 Ts with micaceous shale interbeds. 30 28 25 Dibblee, T.W., Jr., 1987. Geologic map of the Matilija Quadrangle, Ventura County, California: Dibblee Geological 23 25 Qls? 25 Ts Ts Juncal Formation (early to middle Eocene) - Consists of micaceous shale with Foundation Map DF-12, scale 1:24,000. 25 ? Tj Qpa ULT 70 Qpa A - SANTA ANA FA arkosic sandstone interbeds; generally susceptible to landsliding. 26 24 PARID 35 30 YO 55 Earth Technology Corporation (ERTEC), 1981, Seismotectonic study for Casitas Dam and vicinity, Ventura County, 35 Qpa RO Ts 30 D AR California: Report prepared by Ertec Western for U.S. Bureau of Reclamation, Contract No. 1-07-DV-0112, Ertec 15 U Qpa 45 Tv Ku Unnamed conglomerate (late Cretaceous) - Conglomerate with arkosic sandstone 25 24 Tv Project No. 81-159, 96 p., 7 plates, scale 1:12,000. 25 35 28 17 Ts 15 Ts Ts Qpa LT 57 and micaceous shale interbeds. 30 U 55 15 25 A Edwards, R.D., Rabey, D.F., and Kover, R.W., 1970, Soil survey of the Ventura area, California: U.S. Department of 30 Ts F 10 61 43 Tr 24 Qha 10 Qpa Agriculture, Soil Conservation Services, 151 p., scale 1:24,000. Ts 20 A Tr V Qha Qha 15 40 O 30 25 Qpa Tr N Qls? A Evans, J.R., Gray, C.H., Jr., Cleveland, G.B. and others, 1971, Analysis of mudslide risk in southern Ventura County, 45 20 20 25 L Qls Qls? Ts L California, in California Division of Mines and Geology, Open-File Report 72-23, Part 1, 83 p.; and Regional 15 15 Qpa I Qpa Tr Qls? V LT 41 20 32 ? AU Landslide Prediction, Part 2, 33 p. 22 Ts Ts 15 F Symbol Explanation 21 Qpa Qls Qls 25 8 41 24 Qw 44 Tr A 10 ST 25 Tr 40 Huftile, G.J., 1991a, Thin-skinned tectonics of the Upper Ojai Valley and Sulphur Mountain area, Ventura Basin, 30 30 VI Qls? Qw Tr Qha 27 33 Tr California: American Association of Petroleum Geologists Bulletin, v. 75, no. 8, p. 1353-1373. 31 26 A Qls? Contact between map units - Dashed where approximately located or inferred; 47 44 36 Qpa Ts D L Qpa Tr 40 42 Qha Qls Qpa 30 U Tr Qls? 34 Qha Qls? dotted where concealed. Huftile, G.J., 1991b, Displacement transfer between the Red Mountain and San Cayetano faults, in Active folding and Ts Tr ARIDA FAULT 30 35 Tr Qls reverse faulting in the western Transverse Ranges, southern California: Field Trip Guidebook to accompany the ARROYO P 11 Ts 27 Qpa 27 1991 Geological Society of America Annual Meeting, , California, October 20 to 24, 63 p. Qha Qha Qls 36 U Fault - Solid where accurately located; long dash where approximately located; 25 32 31 Qha ? 35 24 45 41 D Qls 33 30 32 25 Tr short dash where inferred; dotted where concealed; queried where location is 33 Tr Qpa U 41 D Huftile, G.J. and Yeats, R.S., 1995, Convergence rates across a displacement transfer zone in the Western Transverse T 56 54 32 30 31 L uncertain. U = upthrown block, D = downthrown block. Arrow and number Ranges, Ventura Basin, California: Journal of Geophysical Research, v. 100, no. B2, p. 2043-2067. 35 35 ? 40 U Qls Qls? Qpa Tr FA Qha Qls? Ts Qls Tml indicate direction and angle of dip of fault plane. Qha 37 Tv CH 61 38 Ts 35 Qpa L Tml Huftile, G.J., 1988, Structural geology of the Upper Ojai Valley and Chaffee Canyon areas, Ventura County, California: Qpa U Tml 25 G 31 Qls 27 S Qls? Oregon State University, M.S. thesis, 103 p. 35 Tr Qha L’ Axis of anticline - Approximately located; dotted where concealed. Arrow Ts 35 Qha 37 VI 50 Tr 14 25 Tv Tr 43 ? Qpa DE Tml indicates direction of plunge. 23 Qls Kahle, J.E., 1985, The San Cayetano Fault and related flexural-slip faults near Ojai and Santa Paula, Ventura County, 25 35 Qpa Qpa 45 58 Tml Qls? 25 Qls California: California Division of Mines and Geology, Fault Evaluation Report FER-174 and Supplement # 1 (1986). 10 37 32 Tr Tr 33 Qls? Axis of syncline - Approximately located; dotted where concealed. Qha 30 Qha Tr Ts 15 25 12 Qpa 24 40 47 Tml Keller, E.A., Johnson, D.L., Clark, M.N. and Rockwell, T.K., 1982, Tectonic geomorphology and earthquake hazard Qpa 38 51 Qha Axis of overturned syncline - Approximately located; dotted where concealed. 31 40 32 Qpa Qpa Qpa Qls north flank, central Ventura Basin, California: U.S. Geological Survey Open-File Report 81-376, 178 p., plate 1, 30 15 34 scale 1:24,000. Qpa Qpa 30 62 67 Qls 60 Tml 25 ? 51 Strike and dip of bedding. 35 Tml ? Qls? Keller, E.A., Rockwell, T.K., Clark, M.N., Dembroft, G.E and Johnson, D.L., 1982, Tectonic geomorphology of the Tml Tml 61 Tmu Tmu Tml D Qpa 67 Vertical bedding. Ventura, Ojai and Santa Paula areas, Western Transverse Ranges, California: Geological Society of America U 50 Cordilleran Section, field guide. 40 51 Qls? 43 47 45 Qls? 21 25 Qls? 25 45 46 25 Strike and dip of overturned bedding. Qls? OAK VIEW FAULTS Qpa 55 44 Kerr, P.F. and Schenck, H.G., 1928, Significance of the Matilija overturn: Geological Society of America Bulletin, v. 39, Qls? D 25 Tml 15 35 23 p. 1087-1101. 20 ? U 61 Qls? 50 20 Qls? Qls? Qpa Qls? 41 24 33 Landslide - Arrows indicate principal direction of movement, queried where 50 35 Tml 20 21 Morton, D.M., 1973, Reconnaissance photo-interpretation map of major landslides, southern Ventura County, 40 10 14 24 17 Qls? 40 32 ? existence is questionable; hachured where headscarp is mappable; some 55 25 California: California Division of Mines and Geology Preliminary Report 14, plate 5, scale 1:48,000. Ts Qls ? 53 61 26 Qls? 34 Qls? 25 Qls? geologic features are drawn within headscarp. 17 41 35 74 48 25 25 Tml Qls? Tmu Morton, D.M., 1976, Reconnaissance surficial geologic map of the Ojai 7.5-minute quadrangle, Ventura County, 27 Tmu Qls 42 52 51 Qha 42 Tsq California: U.S. Geological Survey Open-File Report 76-212, scale 1:24,000. 15 26 16 20 35 Qls? Qpa 68 30 15 Ts Qls Qls? Qha Tml Qls 24 11 Qls? Moser, F.G. and Frizzell, V.A., Jr., 1983, Geologic map of the Lion Canyon, Matilija, Ojai, Wheeler Springs and White 30 25 Qpa Tmu 20 35 Ledge Peak quadrangles, California: U.S. Geological Survey, Open File Report 82-818A, scale 1:50,000. Tr Qls 74 41 62 T 32 25 29 FAUL Qls? 30 25 Tr 62 Qpa Qls N 68 Namson, J. and Davis, T., 1988, Structural transect of the western Transverse Ranges, California: Implications for 25 71 AI 28 25 30 37 26 T 30 Tv 34 Qw 45 Tmu 40 Tsq UN lithospheric kinematics and seismic risk evaluation: Geology, v. 16, p. 675-679. 40 30 Qls 42 40 O Ts Qls 78 29 34 M 32 50 PHUR 32 SUL Rockwell, T.K., 1988, Neotectonics of the San Cayetano Fault, Transverse Ranges, California: Geological Society of 40 Qls 36 Tsq 53 White 50 34 50 Tmu 80 41 80 San Qls 27 45 45 60 60 Tsq Led Paula Pk America Bulletin, v. 100, p. 500-513. 45 Qls 36 Mat Ojai 30 Qha ge Peak Qw 51 34 75 70 Ojai ta Qls Tsq 30 53 ilija Rockwell, T.K., 1983, Soil chronology, geology, and neotectonics of the north central Ventura basin, University of 30 Qha Tmu Qls? 30 Qls? 32 43 Qha 150 30 Tv 23 Tmu 51 50 Sulphur California, Santa Barbara, Ph.D. thesis, 424 p., scale 1:24,000. Qls Qls? Springs Qls Qls 25 30 Tml Oak View 150 Qls Qls Tr 45 Tsq 27 Tr 35 Tmu 57 Tp Rockwell, T.K., Johnson, D.L., Keller, E.A., and Dembroff, G.R., 1985, A late Pleistocene-Holocene soil 26 40 Qls 30 31 45 42 in 56 Pitas101 chronosequence in the central Ventura Basin, southern California, U.S.A., Richards, K., Arnett, R., and Ellis, S., 37 85 54 Ven Sa Santa Paula 27 25 20 San 15 Qls? Qls 60 Poin 33 editors, Geomorphology and soils: London, England, George Allen and Unwin, p. 309-327. 35 35 Qls? 55 tura tico Paula 25 20 Qha 40 ta Tsq 58 y 42 Qls 46 37 62 Qls? t Wilson, R.J., Jones, T.A., and Barrows, A.G., 2001, Earthquake-induced landslide zones in the Matilija 7.5-minute Ts 43 Ventura 126 29 68 Qha quadrangle, Ventura County, California: California Geological Survey, Seismic Hazard Zone Report 064, Section 2, 25 Tml 45 51 34 Qls? 45 Qls? Saticoy 22 Qls? 27 p. 21-51. Qpa 40 49 24 El Rio Tmu 64 Qls 47 Camarillo Tmu 46 Qls Mapping completed Oxnard Camar 45 Qpa 41 Weber, F.H., Jr., Cleveland, G.B., Kahle, J.E., Kiessling, E.W., Miller, R.V., Mills, M.F. and Morton, D.M., 1973, Geology Tv Qls? Qha 42 41 51 53 25 Ts 35 under STATEMAP Oxnard 32 43 44 and mineral resources of southern Ventura County, California: California Division of Mines and Geology Preliminary Qls? 31 61 42 Qha 31 Qls? Qls? 52 77 45 Qls? illo Report 14, 102 p., plate 1, geologic map of southern Ventura County, California, scale 1:48,000. Tr Tml Qpa Tp FY 2002- 03 30 36 46 Tp Tp Qls 1 20 50 44 Point Hueneme 25 Qht 32 61 Weber, F.H., Jr., Kiessling, E.W., Sprotte, E.C., Johnson, J.A., Sherburne, R.W. and Cleveland, G.B., 1975, Seismic Tv Qls? 58 42 Qls Qls 32 Qls? 38 57 FY 2003- 04 hazards study of Ventura County, California: California Division of Mines and Geology Open-File Report 76-05, Qha Qha Mugu Point 35 Qls? 75 44 plates 5A and 5B, scale 1:48,000. 35 Qpa Tmu 31 Qls? Qha 30 51 Tr 22 Tv Tml 36 Tv 35 41 Qls 60 FY 2004- 05 FY 2005- 06 Qls? 45 Qpa Tr Qls 42 42 William Lettis and Associates, 2001, Preliminary digital Quaternary geologic map of the Matilija 7.5-minute quadrangle, o Tr Qls? Tp 52 60 o 34 22'30" 32 Tv Qls 34 22'30" California, digitized at scale of 1:24,000. 119 o22'30" 119 o15'00" Yeats, R.S., 1976, Neogene tectonics of the central Ventura basin, California: Society of Economic Paleontologists and Mineralogists, Pacific Section, The Neogene Symposium, p. 19-32. Topographic base from U.S. Geological Survey This geologic map was funded in part by the Matilija 7.5-minute Quadrangle, 1988 U.S. Geological Survey National Cooperative Yeats, R.S., 1983, Large-scale Quaternary detachments in Ventura Basin, Southern California: Journal of Geophysical UTM projection, North American Datum 1927 Scale 1:24,000 Geologic Mapping Program, STATEMAP Research, v. 89, no. 62, p. 569-583. Award no. 05HQAG0080 Yeats, R.S., Huftile, G.J. and Grigsby, F.B., 1988, Oak Ridge Fault, Ventura fold belt, and the Sisar decollement, Ventura Basin, California: Geology, v. 16, p. 1112-1116. MN 0 .5 1 2 GN Miles Yeats, R.S., Huftile, G.J. and Stitt, L.T., 1994, Late Cenozoic tectonics of the east Ventura basin, Transverse Ranges, California: American Association of Petroleum Geologists Bulletin, v. 7, p. 1040-1074. 14° 1°18' 249 MILS 0 .5 1 2 23 MILS Kilometers USGS 0 1 2 3 SC A M P Copyright © 2006 by the California Department of Conservation California Geological Survey. All rights reserved. No part of UTM GRID AND 1988 MAGNETIC NORTH Thousand Feet CGSCGS DECLINATION AT CENTER OF SHEET this publication may be reproduced without written consent of the Contour Interval 40 Feet California Geological Survey. Dotted Lines Represent Half-Interval Contours "The Department of Conservation makes no warranties as to the suitability of this product for any given purpose."

Revised: 11/06/2006