Ancient Tropical Sea Discovered Beneath Assam

Guwahati: A prehistoric tropical sea once covered parts of Assam. Researchers from the Department of Geology at Nagaland University uncovered evidence that the region sat under warm, shallow waters 50 million years ago. The study focused on Sylhet Limestone deposits at Dillai Parbat in the Karbi Anglong district. It dates back to the Eocene Epoch.

The team, led by Prof. S.K. Srivastava and research scholar Tsenchumo Lotha, used petrography and micropaleontology to analyze limestone, shale, and sandstone. Their findings appeared in the Journal of Geosciences Research. The data shows the area was once a nutrient-rich lagoon teeming with microscopic marine life. Prof. Srivastava noted, "The evidence indicates that the limestone was deposited in a shallow marine, warm-water environment with favourable ecological conditions for microfaunal growth."

Geological signatures reveal the ancient seafloor suffered periodic disturbances from storms. These events left lasting patterns in the sediment. Tectonic shifts also altered the basin conditions over time. Lotha emphasized the need for lab work to confirm field observations. He stated, "Things are not always clear when we are in the midst of fieldwork. But when we connected the same with lab results, the overall picture started becoming clearer."

Nagaland University Vice-Chancellor Prof. Jagadish Kumar Patnaik praised the work. He called it a major scientific contribution to the geological record of Northeast India. The study provides a framework for future basin analysis and climate evolution research across the region.