Unnamed Asbestos prospects  (Prospects East of Russellman), North Peak, Mount Diablo (Mt Diablo), Clayton, Diablo Range, Contra Costa Co., California, USA
|Latitude & Longitude (WGS84):||37° 55' 2'' North , 121° 54' 21'' West|
|Latitude & Longitude (decimal):||37.91750,-121.90611|
|Köppen climate type:||Csb : Warm-summer Mediterranean climate|
An asbestos occurrence/prospects located in the SW¼SE¼ sec. 19, T1N, R1E, MDM, 2.8 km (1.7 miles) NNW of North Peak (coordinates of record) and 3.6 km (2.3 miles) SE of Clayton, at the northern foot of the peak. MRDS database states locality is in Russellmann Park; however, the coordinates provided map to a point N of the park.
Some asbestos has been found in the serpentine. Local rocks include Lower Cretaceous marine rocks.
Commodity ListThis is a list of exploitable or exploited mineral commodities recorded at this locality.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
100.5 - 145 Ma
|Great Valley Sequence Unit A - Shale, with minor sandstone|
Age: Early Cretaceous (100.5 - 145 Ma)
Comments: Great Valley Sequence
Reference: Graymer, R.W., D.L. Jones, E.E. Brabb. Preliminary geologic map emphasizing bedrock formations in Contra Costa County, California. U.S. Geological Survey Open-File Report 94-622. 
|Aptian - Berriasian|
113 - 145 Ma
|Lower Cretaceous marine rocks|
Age: Early Cretaceous (113 - 145 Ma)
Stratigraphic Name: Espada Formation; Horsetown Formation; Marmolejo Formation; Ono Formation; Paskenta Formation; Rector Formation; Shasta Series; Toro Formation; Wisenor Formation; Great Valley Sequence; Stony Creek Formation; Lodoga Formation; Budden Canyon Formation
Comments: Coast Ranges. Middle part of Great Valley Sequence. Thick, extensive sequences of shale, siltstone, sandstone, and conglomerate. Included in undivided Lower Cretaceous and Upper Jurassic rocks on many recent maps
Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052.