[MIS29-P01] Characteristics and origin of sediments collected from mud volcanos off Tanegashima
Keywords:Mud Volcano, X-ray CT scan, 10Be, Off Tanegashima
The sediment cores of MV # 2 and MV # 3, including the results of X-ray CT scan and MSCL measurement, showed that many gravels were seen from the top to the bottom of the whole core, and the number of gravels increased toward the top It was confirmed that there was no sediment covering. This indicates that pebbles are included in the sediments, which is a characteristic of mud volcanoes, and since no pelagic sediments are seen, both MV # 2 and MV # 3 are currently active mud volcanoes. It was confirmed that it was. In terms of dating by 10Be dating, MV # 2 shows an old age of around 7.0 to 11.1 Ma, and MV # 3 shows an old age of around 10.3 to 11.8 Ma, which clearly indicates that it originated from sediments of that era became. As for XRD clay minerals, both MV # 2 and MV # 3 have more illite and less smectite when compared to the mud volcano off Kumano. Therefore, the peak of the illite smectite mixed layer was not observed, the count of illite was large, and the smectite was low. Therefore, this deposit experienced a temperature of 160 ° C. or more and was dehydrated. The result is a higher temperature than the mud volcano off Kumano, which shows the peak of the mixed layer of illite and smectite. Based on these results, two MV # 2 and MV # 3 off Tanegashima, MV # 2 and MV # 3, of mud volcanoes, light-weight sediments from deep underground rolled up gravel from new strata of various ages. MV # 2 and MV # 3 were found to have been derived from strata of the same origin.