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Department of Earth and Planetary Sciences, University of Allahabad, Allahabad-211 002, Uttar Pradesh, India E-mail : ambalika.niyogi@gmail.com EPMA Laboratory (PLANEX), Physical Research Laboratory, Thaltej Campus, Ahmedabad-380 009, Gujarat, India Manuscript received 13 January 2014, accepted 15 January 2014 Spherules of anthropogenic, biogenic, geogenic and cosmogenic origins are difficult to distinguish based on their size, shape, surface features despite their importance to elucidate large scale geological events such as mass extinction, palaeoclimate change, and meteoritic impacts etc. Rapid industrialization and vehicular emissions have added several other types of spherules. However, chemical analysis of different types of spherules, especially major element chemistry, has been found useful to differentiate spherules of diverse origins. |
