Geochemical Studies of Detrital Zircon Grains from the River Banks and Beach Placers of Coastal Odisha, India

Zircon grains are reasonably ubiquitous in river banks and beach placers as detrital minerals, including along the similar to 1700 km long Indian east coast, from Odisha state to the state of Kerala. Zircons from beach placers and river banks located along the eastern part of Odisha, India, were studied using LA-ICP-MS in order to delineate their geochemical characteristics. Hf (mean = 11270 ppm) and Y (mean = 1064 ppm) were the two most abundant trace elements found within zircon grains as compared to other trace elements. The abundance of uranium was observed to be 2-4 times larger than that of thorium. Zircon overgrowths formed in equilibrium with a partial melt and were similar to magmatic zircon in terms of the high Y, Hf and P content, steep heavy-enriched REE pattern, positive Ce anomaly and negative Eu anomaly. The average low Th/U ratio of the studied zircon grains distinguished them from the magmatic ones. The REE present in zircon grains was restricted to high-grade metamorphic events. The result of the present study would be useful for delineating the source region and the efficacy of resource potential and indigenous export.

Automated summary

Zircon grains are commonly found in river banks and beach placers along the Indian east coast, with high abundances of Hf and Y elements compared to other trace elements. The study revealed that the abundance of uranium in zircon grains is larger than that of thorium. The geochemical characteristics of zircons in terms of REE content and Th/U ratio distinguish them from magmatic zircons. This study provides valuable information for determining the source region and assessing the resource potential and indigenous export.