Soil Formations: Geologic Classes and Characteristics - Geotechnical Engineering Investigation - page 548

TABLE 7.9
Identification Properties of the Tertiary Formations in the Los Angeles Area a

Material Description Dry Unit Natural Liquid Plastic Plastic % Smaller % Activity

Activity Weight Water Limit Index Limit Than Smaller

(pcf) Content 0.002 Than 200

(%) mm Sieve

Weathered Stiff brown and gray silty clay 89.8 28.7 66 31 35 34 85 0.91

clayey Modelo thin bedded with some light-

gray fine sand

Unweathered Hard, dark-gray silty clay thin 98.2 23.3 69 37 32 31 84 1.19

clayey Modelo bedded with some light gray

fine sand

Sandy Modelo Compact, light gray and tan, 110.4 16.5 NP — NP 6 26 —

fine to medium sand, some silt,
occasional seams

Weathered Soft to medium stiff, 103.6 22.1 62 38 24 30 73 1.26

clayey Martinez brown clayey silt and silty clay

Weathered sandy Medium compact, rust brown 108.2 17.6 NP — NP 14 42 —

Martinez and yellow silty fine to medium

sand

Unweathered Very compact, gray-green clayey 120.7 12.8 NP — NP 16 38 —

sandy Martinez fine lo medium sand with

calcareous concretions

Unweathered Hard, dark gray-green clay with 105.6 19.2 68 40 28 30 80 1.33

clayey some pockets of gray medium to

Martinez fine sand, occasional shale

fragments

a

From Gould, T.P., Proceedings of ASCE, Research Conference on Shear Strength of Cohesive Soils , Boulder, CO, June 1960. With permission.