Studies on the mineralogy, geochemistry and origin of the modern sediments of the ashtamudy lake, Kerala

This study enfolds the environment of deposition and the lateral variation in texture, mineralogy and geochemistry of the Ashtamudy lake sediments. While the heavy mineral and clay mineral investigations enable us to decipher the nature, texture and source of sediments; organic matter and carbonate contents and the geochemical analysis of major and minor elements help establish the distribution and concentration of the same in regard to the various physico-chemical processes operating in the lake. Study of trace elements holds prime importance in this work, since their concentrations can be used to outline the extent of contaminated bottom area, as well as the source and dispersal paths of discharged_pollutants. In short, this study brings out a vivid picture of the mineralogy and geochemistry of the lake sediments in different environments, viz., the freshwater, brackish water and marine environments that are confined to the eastern, central and western parts of the lake respectively. For the better understanding and expression of the results of the analysis, the lake has been divided into 3 zones namely: eastern part, central part and western part.

THE RED RAIN PHENOMENON OF KERALA AND ITS POSSIBLE EXTRATERRESTRIAL ORIGIN

A red rain phenomenon occurred in Kerala, India starting from 25th July 2001, in which the rainwater appeared coloured in various localized places that are spread over a few hundred kilometers in Kerala. Maximum cases were reported during the first 10 days and isolated cases were found to occur for about 2 months. The striking red colouration of the rainwater was found to be due to the suspension of microscopic red particles having the appearance of biological cells. These particles have no similarity with usual desert dust. An estimated minimum quantity of 50,000 kg of red particles has fallen from the sky through red rain. An analysis of this strange phenomenon further shows that the conventional atmospheric transport processes like dust storms etc. cannot explain this phenomenon. The electron microscopic study of the red particles shows fine cell structure indicat- ing their biological cell like nature. EDAX analysis shows that the major elements present in these cell like particles are carbon and oxygen. Strangely, a test for DNA using Ethidium Bromide dye fluorescence technique indicates absence of DNA in these cells. In the context of a suspected link between a meteor airburst event and the red rain, the possibility for the extraterrestrial origin of these particles from cometary fragments is discussed.