Weathered rims around core-stones show alteration of serpentinite to start with the opening-up of grain boundaries and formation of micro-cracks (Stage 1) followed by staining along chrysotile veinlets (Stage 2). Plastic and liquid limits have limited variation ranging from 24 to 33%, and from 36 to 50%, respectively. Increasing fine clay (<2 μm) contents up the profile from 34 to 43% in saprock to 40 to 51% in sub-zones IA and IB indicate that pedological processes result in continued disintegration of weathered serpentinite. Particle size distributions are variable with depth silt contents decreasing from 38 to 58% in saprock to 28 to 44% in the pedological soil zone. ![]() Constant volume samples show the earth materials to be rather loose with dry unit weights of 10.32 to 16.28 kN/m3 and porosities of 39 to 60%. ![]() ![]() whilst the bottom bedrock zone consists of serpentinite with effects of weathering along discontinuity planes. ![]() The intermediate, 1.5 m thick, saprock zone consists of brown, stiff, silty clays with indistinct relict fault planes and core-stones. Three broad morphological zones can be differentiated the top, 2.5 m thick, pedological soil comprising IA and IB sub-zones of brown, soft clays, and IC1 and IC2 sub-zones of reddish brown, stiff silty clays with lateritic concretions and lateritized core stones.
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