Mineralogy and trace element studies in the soils of Mussoorie Forest Division, Uttarakhand

Abstract

An attempt has been made to study the mineralogy and distribution pattern and concentration trends of trace element in the soil clay fractions and parent material of Maldeota, Satengal and Dhanaulti in Mussoorie forest division, Uttarakhand. Light minerals constituted bulk of sand fractions and comprised quartz, feldspar and mica in order of their abundance. Heavy minerals contributed small fractions and were dominated by opaque minerals, calcite, chlorite, zircon, hornblende etc. Clay fractions are characterized by illite as the dominant clay mineral associated with appreciable amount of kaolinite, mixed layer minerals, chlorite and small amounts of vermiculite, calcite and quartz. Chemical analysis of clay fractions indicates that the soils developed over quartzite, black shale, phosphorite and phyllite, do not show marked variation in silica-sesquioxides as well as silica-alumina ratios within the profiles, whereas in the profiles developed over dolomite and limestone, impoverishment of the sesquioxides in the upper horizons was noticed. This has resulted in the increase in the content of silica in the clay complex of the latter soils as also an increase in silica-sesquioxides ratio at the surface. Trace element studies of rocks and clay fractions show significant correlation between the trace elements (Viz. V, Cr, Co, Ni, Zn, Bo etc.) available in rocks and corresponding clay fractions.