Fossils In The Caves Of India #1

[caveindia]

Before talking about the fossils, let me give you some background on the caves of Meghalaya (Northeast India). Since 1992, annual expeditions by European and US cavers, mapped more than 300 kms of cave passages in numerous caves. The exploration is supported locally by the Meghalaya Adventurers Association as a part of the “Abode of the Clouds Project”. I have been to India five times so far.

During December 2012 expedition to the West Khasi Hills, Meghalaya, a 5-member exploration team from Meghalaya and the US explored a spectacular river cave, Krem Amarsang (krem=cave in the local Khasi language), formed in Siju Limestone Formation. The cave entrance (360m asl), located deep in the jungle, is adorned with stone pendants, and leads steeply over large boulders to a lower gallery where a stream emerges from under the breakdown. The cave is decorated with large rust-colored flowstone curtains, rimstone dams as well as stalagmites and stalactites.

Uniquely, much of the course of the underground river follows a succession of symmetrical dissolutional potholes with diameters often exceeding three meters indicating substantial volume and velocity of water. Margins where consecutive potholes meet form razor sharp edges. Beyond the second 3-meter waterfall, the river passage bifurcates. The cave was partly mapped (length = 743m; depth = -40m) with both river passages continuing with no end in sight. Horseshoe bats, fish, crayfish, snails, spiders, and crickets were observed.

In this context, the Eocene Siju Limestone offers an abundance of fossils, particularly nummulites (foraminifera). These fossils are found in the limestone outside as well as inside the cave. Since as a principle we do not remove any rocks, formations, or fossils from caves, no cave fossils were collected. The cave walls are clean-washed rock and the fossils that I observed and photographed in situ were embedded in the limestone bedrock. Because we were making a map of the cave and exploration required bolting and ropes, I only had the time to take several pictures of the fossils in the cave – see photos A1-A2 for examples of what we saw in the upper part of the cave. I believe that these photos show nummulites of various sizes, but I do not know if these might represent different species or the size is dictated by the number and hypertrophy of the protist cells contributing to each colony. Please feel free to correct me, as I am essentially new to fossil identification.

So far, these fossils seem ordinary, however deeper in the cave, and at the last point of the exploration, I found an intriguing fossil, which I will present in my next post. Any comments will be much appreciated.

Mike

[garyc]

Sounds like the adventure of a lifetime. Fascinating!

[caveindia]

>>"Sounds like the adventure of a lifetime. Fascinating!"

Thanks! Sure it was. Earlier today, I have posted two pictures from the cave exploration in my post at the Members Board - Introductions - Hello From Little Rock Arkansas

Edited February 3, 2013 by caveindia