Granitic alluvium

Figure 15 Measured total organic C versus depth and modeled amounts of three fractions of differing residence time ( 10° yr, 10 yr, and 10 yr) for a 600 ka soil formed on granitic alluvium in the San Jaoquin...

Harden J. (1987) Soils developed in granitic alluvium near Merced, Cahfomia. US Geol. Surv. Bull. 1590-A, pp. A1-A65. 

White A. F., Blum A. E., Schulz M. S., Bullen T. D., Harden J. W., and Peterson M. L. (1996) Chemical weathering rates of a soil chronosequence on granitic alluvium I. Quantification of mineralogical and surface area changes and calculation of primary silicate reaction rates. Geochim. Cosmochim. Acta 60, 2533-2550. 

Basalt, with desert varnish Same basalt, without desert varnish Coarse granite alluvium (0 1 mm)... 

Reg soils are closely associated with desertic regions. They have developed on stable surfaces where coarse, gravelly desert alluvium is exposed, and are characterized by a well-developed desert pavement and exhibit some well-defined soil horizons. They occur mostly on depositional surfaces where stones and gravels have been deposited since Neogene times. The surfaces commonly consist of stony, unconsolidated sedimentary deposits in which limestone, dolomite, chalk, flint and marl predominate, together with some fines (silt and clay). Sandstone and granite debris have also been reported to contribute to Reg formation. Less frequently, they form on sedimentary bedrock (Fig. 1.5). 

Residual (Granite) soil Residual (Sedimentary rock) soil Coastal/river alluvium... 

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