image: In the lab, the stalagmites are cut open lengthwise and sampled along their main growth axis by drilling out small amounts of calcite powders. The powders are then analyzed for their chemical composition, which reflects the composition of the drip water at the time the calcite was formed. In the caves of Borneo, changes in drip water composition can be interpreted as past changes in precipitation. Separate samples taken for radiometric dating allow assigning a time to each layer in the stalagmite. This image relates to a paper that appeared in the May 3, 2012, issue of Science Express, published by AAAS. The paper, by Anna Nele Meckler at the California Institute of Technology in Pasadena, Calif., and colleagues was titled, "Interglacial Hydroclimate in the Tropical West Pacific Through the Late Pleistocene." view more
Credit: Image courtesy of Dr. Nele Meckler