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Showing posts with the label Gandak

Geochemistry of Iodine with special reference to Bihar state of India.

Iodine deficiency is an important global health problem. 8 person out of every hundred, suffer from goiter in India. by Dr. Nitish Priyadarshi Halogens are present and are volatile trace elements in most geological samples. Among them, iodine has the lowest abundance; less than 0.1 ppm in igneous rocks and less than several ppm in sedimentary rocks. Iodine is least abundant of the halogens and is lithophile element. It is typically a dispersed element and is never concentrated enough in rocks or sediments to form independent minerals. The content of iodine is higher in air masses of marine origin than in those over the continents (Rankama and Sahama, 1950). The content of iodine seems to have some relationship to the salinity of the sea water as it is found to increase to the rise in salinity. Iodine is carried away from the atmosphere partly by rainwater and partly by direct adsorption into the soil and into plants. High solubility of iodine makes it enriched in soil and its highest c...

Radiogenic Osmium in Ganga river sediments of India.

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Ganga river Sediments are the major source of radiogenic Osmium. by Dr. Nitish Priyadarshi The Ganga sediments are characterized by high Re/Os (rhenium-osmium) ratios and are extremely radiogenic as evident from their 187 Os/ 188 Os isotopic ratios. Samples from the tributaries Alaknanda, Bhagirathi, Gandak and Ghaghra show pronounced 187 Os/ 188 Os. High Os concentrations combined with sediments flux makes the Ganga an important source for soluble Os isotopic evolution in oceans. Interest in rhenium-osmium systematics in rivers has risen sharply in recent years due to the revelation of changes associated with sea water Os isotopic compositions during the past 70 Ma. Radiogenic 187 Os is produced from the β- decay of 187 Re. Osmium isotopic composition in sea water is derived from the weathering of basaltic and peridotitic oceanic crust, hydrothermal solutions, additions from cosmic dust and continental weathering products. Os isotopes in the oceans convey the then prevalent continenta...