Ghilotti Brothers Quarry (Ghilotti Brothers - Marin Company Quarry; Bowman Canyon Quarry; McIsaccs Quarry), Novato, Marin Co., California, USA
|Latitude & Longitude (WGS84):||38° 8' 22'' North , 122° 37' 10'' West|
|Latitude & Longitude (decimal):||38.13959,-122.61966|
|Köppen climate type:||Csb : Warm-summer Mediterranean climate|
A crushed stone deposit/quarry located in sec. 34, T4N, R7W, MDM, 5.6 km (3.5 miles) NW of Novato, at the N end of Bowman Canyon. Operated by Ghilotti Brothers, Inc., California (1981). MRDS database stated accuracy for this location is 100 meters. The pit is located on the Rancho Novato land grant.
Mineralization is serpentinite. Local rocks include ultramafic rocks, chiefly Mesozoic, unit 3 (Coast Ranges and Western Klamath Mountains).
Workings include unspecified surface openings.
Commodity ListThis is a list of exploitable or exploited mineral commodities recorded at this locality.
No minerals currently recorded for 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
|Late Jurassic - Middle Jurassic|
145 - 174.1 Ma
|Ultramafic rocks, chiefly Mesozoic, unit 3 (Coast Ranges and Western Klamath Mountains)|
Age: Jurassic (145 - 174.1 Ma)
Stratigraphic Name: Josephine Peridotite
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. 
145 - 201.3 Ma
|Ultramafic rocks, Coast Range Ophiolite|
145 - 201.3 Ma
Age: Jurassic (145 - 201.3 Ma)
Stratigraphic Name: Franciscan Complex
Description: Serpentinite: Including relatively fresh ultramafic rock; crops out as lenses and irregularly shaped masses, largely within and along boundaries of fsr; most serpentinite displays a prominent shear fabric
Reference: Blake, M.C. Jr., R.W. Graymer, and D.L. Jones. Geologic map and map database of parts of Marin, San Francisco, Alameda, Contra Costa, and Sonoma Counties, California. U.S. Geological Survey Miscellaneous Field Studies MF 2337.