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The concentration of radioisotopes rBe, ~S were measured in Bombay since 1956 and ~2Na, ~a~ z~Si since 1963. In Khandala and other stations such measurements have been made at irregular periods since 1961. In addition several measurements especially that of 32Si were made in 1970. Data available todate from Indian stations is summarised and critically analysed. We conclude that appreciable amounts of ~S, 2~Na and 8JSi, over and above their production by cosmic rays, were produced during the high yield Russian tests as evidenced by their fallout between 1962-66. Based on the bomb produced excess the half period for their removal from the stratosphere is deduced to be less than 1 year. The ' excess' contribution of 3aSi due to bombs is, however, small; about 1~0 of its inventory in the oceans. The present study shows that for stations where orogeny is the principal mer nism of precipitation, the annual fallout is independent of the annual rainfall.

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Relic carbonate deposits along the western margin of India occur as dolomite crusts, aragonite sands (pelletal / oolitic) and aragonite-cemented limestones, oyster shells, corals, encrusted coralline algal and foraminiferal-dominated nodules. The petrology and mineralogy of the deposits indicate that except for aragonite sands and foraminiferal nodules, the others were formed in shallow marine conditions and serve as sea level indicators. Radiocarbon dates were measured for 62 relic deposits covering the entire margin. The age of these deposits on the continental shelf off Cape Comorin and Mangalore, between 110 and 18 m depth, ranges between 12, 610 14 C yr BP and 6,390 14 C yr BP. On the northwestern margin of India, especially on the carbonate platform (between 64 and 100 m), the age ranges from 17,250 to 6,730 14 C yr BP. The relic deposits of the Gulf of Kachchh at depths between 35 and 25 m are dated at 12,550-9,630 14 C yr BP. The age vs. depth plot of the relic deposits further indicates that the Gulf of Kachchh was inundated much early, atleast by 15 ka, after the Last Glacial Maximum, and was subjected to uplift and subsidence during the Holocene. The carbonate platform subsided during the early Holocene. Some of the relic deposits between Cape Comorin and Mangalore plot on or, closely follow the glacio-eustatic sea level curve. Despite abundant siliciclastic flux discharged by the Narmada and Tapti during the early Holocene, the platform off these rivers is largely devoid of this flux and carbonate sedimentation continued until 6,700 14 C yr BP. We suggest that the river-derived sediment flux diverted southwards under the influence of the SW monsoon current and, thereby, increased the turbidity on the shelf and slope southeast of the carbonate platform and facilitated the formation of deeper water foraminiferal nodules off Vengurla-Goa.