An analysis of free‐air, Bouguer, Pratt‐Hayford (D = 113.7 km), and Airy‐Heiskanen (T = 30 km) anomalies visa vis elevation in India indicates that on an over‐all basis isostatic equilibrium prevails in India. Regression study of Bouguer anomalies versus elevation made by grouping the data according to tectonic and geologic units shows that the Bouguer anomaly decreases rather slowly with the increase in elevation over the Himalayas, Aravallis, Nilgiris, Eastern Ghats and the Assam plateau, all of which are post‐Mesozoic rejuvenated blocks of the Archaean shield. Small, and sometimes even positive regression coefficients characterize these blocks; the isostatic anomalies are found to be near zero or positive. It is concluded that the uplifting of these shield blocks has probably taken place through movement and incorporation of material from the upper mantle into the crust.

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SummaryTrace elements in twenty samples of the Closepet granite (grey and pink varieties) and the related rocks have been determined by neutron activation analysis (Th, Rb, and Cs), fluorometry (U), flame-photometry (K), and emission spectroscopy (Pb, Sr). The trace element contents of the grey and pink varieties are generally similar. An analysis of the magnitudes of the trace element and other ratios (K/Rb, 235; Th/U, 6·4; U/K (× 104), 0·7; K/Cs (× 10−4), 3·6; Th/K (× 104), 5·3; Fe2O3/(FeO+Fe2O3), 0·27) as well as 87Sr/86Sr initial ratio (0·705; Crawford, 1969) of the Closepet granite indicate two possible modes of genesis: Either the granite magma was not highly differentiated and the vapour phase was relatively insignificant; the crystallization of the magma took place under essentially non-oxidizing conditions; the pink variety, which followed the grey variety, crystallized under essentially the same conditions as the grey variety. Or the Closepet granite had a two-stage history—palingenesis (starting from the Peninsular gneiss) and metasomatism involving the enrichment in K, Rb, Pb, and Th and depletion of Sr and Cs, among others.