Granite weathering products

These observations support the hypothesis that the similarity of the cesium elemental distribution to that of iron in natural granite weathering profiles is a result of coincidental clay mineral production rather than a direct association with oxyhydr-oxides (14).. .. 

TABLE 7.2 The composition of a granitic-type rock and of its weathering products ... 

DEEP WEATHERING AND ALTERATION IN GRANITES - A PRODUCT OF COUPLED... 

The sediment was deposited near-shore in shallow water of a basin that was slowly subsiding. The sediment was derived from an area of low relief as weathering products of granitic rocks. The rocks of the Greenlee Formation dip south at 45° to nearly 90° and may form the limb of a major fold, the axis of which presumably trends east-west. Wade and Cathey (1986) estimated that the thickness of the Greenlee Formation exceeds 13 km provided that the exposure along the Shackleton Glacier is a continuous sequence without repetitions. 

Pavich, M. J. (1986). Processes and rates of saprolite production and erosion on a foliated granitic rock of the Virginia Piedmont. In "Rates of Chemical Weathering of Rocks and Minerals" (S. M. Coleman and D. P. Dethier, eds), pp. 551-590. Academic Press, New York. 

The Hostrock and Backfill Material. Most crystalline igneous rocks, including granite and gneiss, are composed of a comparatively small number of rock forming silicate minerals like quartz, feldspars (albite, microcline, anorthite etc.) micas (biotite, muscovite) and sometimes pyroxenes, amphiboles, olivine and others. Besides, there is a rather limited number of common accessory minerals like magnetite, hematite, pyrite, fluorite, apatite, cal cite and others. Moreover, the weathering and alteration products (clay minerals etc.) from these major constituents of the rock would be present, especially on water exposed surfaces in cracks and fissures. 

China Clay, The product obtd by leaching weathered deposits of granitic rocks, so that quartz mica portions are removed (Ref 1). For example, when Feldspar weathers, the first product is Cornish stone this next becomes china clay rock from which the china clay is obtd. The purest china clay is known as kaolin and consists mainly of hydrated aluminum silicate(Ref 2)... 

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