Deccan Traps

The Late Cretaceous to Palaeocene (~65 Ma) Deccan Traps continental flood basalt province contains hundreds of tholeiitic basalt lava flows. Each flow represents a dyke-fed fissure eruption similar to, but vastly larger than, modern Hawaiian and Icelandic eruptions. With individual 1000 km3 eruptions releasing 10 gigatons of carbon dioxide and sulphur dioxide each to the atmosphere, Deccan volcanism played a critical role in the Cretaceous/Palaeocene (K/Pg) boundary mass extinction. The province still covers 500,000 km2 in west-central India, excluding substantial parts downfaulted into the Arabian Sea during India-Seychelles rifting at 62.5 Ma, or eroded away. The still-preserved basalt thickness (including subsurface thickness) in the Western Ghats escarpment, beside the rifted margin, is ~2 kilometers. Mahabaleshwar town (1436 meters above mean sea level) in the Western Ghats sits atop an ~1200 meter-thick sequence of about 50 lava flows, capped by a thick, regional ferricrete duricrust formed by Palaeogene weathering. The Mahabaleshwar section is the most intensely studied stratigraphic section in the province for petrology, geochemical stratigraphy, geochronology and palaeomagnetism. Mahabaleshwar, with its pleasant climate, great scenic beauty and easy access, also attracts hundreds of thousands of tourists every year, and thus has very high geoheritage and geotourism value (Sheth, 2014).