Study Of Micro-Morphology, Major Element Geochemistry and Palaeoclimatic Implications Of Calcrete Deposits At Salukkuvarpatti Village, Near Pandalgudi, Viruthunagar District, Tamilnadu, India.

Calcrete has been formed as a widespread deposit in the regolith part centered on Salukkuvarpatti village and its surroundings near Pandalgudi region, Viruthunagar District of Tamilnadu. The schematic stratigraphic profile succession of calcrete deposit of the study area is cited. The macroscopic forms of calcrete of the study area are gravel, nodular, lumpy, hardpan and chalky nature. The microscopic observation reveals that microcrystalline or microsparitic calcite precipitation forms rimming around detrital quartz, feldspar and the other sap rock grains biotite, hypersthene and hornblende. Sometimes, it shows veining, void lining, lensoidal, and meshwork, displacive and replacive forms of precipitation. The major element geochemistry of calcrete indicates that CaO, SiO2, Al2O3 and Fe2O3 are in more elevated concentration than the other oxides such as a MnO, MgO, Na2O, K2O, TiO2 and P2O5. The major element geochemistry and clay minerals content in calcrete deposits are used as proxies to explain thepalaeoclimatic conditions as arid and semi-arid.