Chemical analyses of black material within fault-related sample by Taiwan Chelungpu-Fault Drilling Project

In order to understand the faulting mechanism at the 1999 Chi-Chi earthquake in Taiwan, the TCDP Hole B core samples were measured nondestructively and continuously in the Kochi core center. The core samples include three fault zones (1137mFZ, 1194FZ and 1243mFZ), and their MSCL (Multi Scanning Core Logger) data show high magnetic susceptibilities and low wet-bulk densities. The former means high concentration of magnetic minerals. On the other hand, each fault zone has black material which looks like shale or coal. We just try to conduct several chemical analyses to reveal that it is pseudotachylyte or carbonaceous one with much magnetic minerals. We will present the preliminary results of these analyses.