Geologic Map of the Rainbow Basin Fault Area: Explanation Barstow, California Correlation of Map Units and Map Location R2W R1W 35.03818 N 35.03788 N -117.04461 W -117.02566 W Recent Alluvium 12 Qal 90 MN 20 Qal Mp Mbol 83 Upper member, 12° 28’ E 17 Mbs D 17 Skyline member Mbb Qal Skyline Tu 29 Middle member U D Unk Mbou Mbou 58 50 Above Oreodont 44 32 51 58 48 61 Oreodont Tu 42 52 40 41 39 15 Middle member 41 41 33 U 27 Mbol Mbol Below Oreodont 22 21 21 43 9 34 32 17 25 34 35 31 Rak Tu 33 30 16 27 36 24 26 17 30 30 19 Lowest member Qal 22 Mbb 31 Owl Conglomerate Mbou Mbol 25 Red Tu 39 39 47 Mp Miocene Unmapped 44 Pickhandle Fm. Unk Portions T11N T11N 32 24 Mbou Description of Map Symbols 26 26 Contact Folds Fault Scarp 31 Dashed where appropriate Syncline, anticline Ball on downthrown side Mbol Qal Major & Minor Faults Fault Township & Range Dashed where inferred: Low angle strike slip Section lines and Mbol Stratigraphic throw as indicated (example is left lateral) number D 8 U 30 10 D 47 30 21 56 39 25 30 30 U Unk 32 45 Attitude of Bedding Attitude of Fault Fault Zone or Shear Zone Mbb 42 7 8 Width to scale 32 38 53 31 31 26 67 D Mp U Mp Description of Map Units 35.01784 N 35.01635 N -117.04673 W R2W R1W -117.02469 W Qal ALLUVIUM - Silt, sand, and gravel along streams and erosional 250 0 250 500 750 1000 m features. Some large cobbles and boulders near stream axis. 1000 0 1000 2000 3000 4000 ft Contour interval 25 ft UPPER MEMBER (North Limb) - Largely ne-grained lacustrine shale, Datum is mean sea level Mbs mustone, and claystone. Light gray-brown to rusty yellow, poorly consolidated and sorted conglomerate and sandstone, mostly granitic and volcanic detritus; some limestone, sandstone and tu. 3300 ft UPPER MIDDLE MEMBER - Mostly sandstone separated by beds of Mbou claystone and limestone; brown tuaceous bentonite and white Cross Section Description limestone makes up the lower boundary: Oreodont Tu. 3200 ft LOWER MIDDLE MEMBER - Green and gray sandstone with yellow and 3100 ft Mbol greenish-gray claystone with mostly lacustrine sediment towards its base and progressively more sandstone towards its summit. Mbb 3000 ft OWL CONGLOMERATE MEMBER - Conglomerate, gray to green-gray, Qal Mbb crudely and locally cross-bedded, poorly consolidated, composed of Mbs subrounded cobbles and boulders. Unconformable contact at base 2900 ft with Pickhandle Formation. Mbol Mp 2800 ft Mp PICKHANDLE FORMATION Mbb Mp Mbou ? ? 2700 ft 11°NE 1000 ft 2000 ft 3000 ft 4000 ft 5000 ft 6000 ft 7000 ft By Caleb Stanton 06/03/12.