Jeju Island is a Live Volcano (image) Korea Institute of Geoscience and Mineral Resources (KIGAM) Share Print E-Mail Caption These are pictures of the sedimentary layer containing charcoal found on a stony mountain developing site in Sangchang-ri, and the carbonized wood sample used for the radiocarbon dating. Thick lava covers the upper gravel layer. Credit KIGAM Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.