Hidden Earth 2017

Exploration of Krem Puri, 12km and already the Second Longest Sandstone Cave in the World

30 minute Lecture|Dr Mark Tringham

Abstract

The 2016 and 2017 Meghalaya expeditions have been exploring an unusual sandstone cave, Krem Puri or ‘Fairy Cave’ in N.E. India. Already over 12 km in length it is the 2nd longest sandstone cave in the world., After further exploration it will have the potential to become the longest if it overtakes Yeuta (18km) in the ‘Tepui’ region of Venezuela. Krem Puri is a 2D maze cave formed in Cretaceous sandstones which are a few hundred metres thick and which form a deeply dissected plateau around the town of Mawsynram. The cave appears to have formed over a narrow stratigraphical interval (~20m) where the sandstones contain a calcareous cement. A relict phreatic inception horizon occurs and active rift-like vadose canyon passages extend above and below with several streamways found. More work is required to complete the exploration and understand the speleogenesis in such an unusual lithology. Aside from rare calcite speleothems, unusual ‘sandmen’ sandstone formations occur in a few places which resemble stalagmites but which are not drip-related. These are new to science and they and other features will be investigated further in 2018 as the cave gradually gives up its secrets.