Study of World Ocean Floor by Drilling & Down hole Measurement

点击翻译按钮获取中文摘要

The research conducted this year includes the tectonics, sedimentation, petrology and paleoenvironments of the Atlantic Ocean. The mechanism of the breakup the Pangea and the birth of the Atlantic Ocean has been the one of the major objectives of the earth sciences. This program investigated the Greenland offshore penetrated an entire section of so-called seaward dipping reflector and found that the breakup was accompanied by dome uplift, emplacement of enormous basaltic magma which followed by rapid subsidence. This sequence of event suggests that the continental breakup and greenhouse earth was associated with mantle plume. This finding is a major break through in the earth science.The program also made a major contribution in the field of paleooceanography. The deep seas drilling in the area of northern Atlantic showed that the initial development of the polar ice sheet started about 7.5 Ma and massive development about 2.5 Ma. The high frequency cold-warm signals with duration of several thousand years were detected as a change in sea surface temperature concordant with the results of the Greenland ice core data. This produced a truly new insight into the climatic behavior and previous view of ice age climatic picture have to be reconsidered with new perspectives.Samples and data brought from the drilling vessel have been analyzed in cooperation with partner countries' scientist. Continuos discussion has been carried in the various committees and panels for the evaluation of results, science planning and future direction. An important meeting was held in Kyoto for the future planning of ocean drilling. An consensus was reached ; need for deep drilling and strong program of borehole observatory for earth interior tomography. The future direction of ocean drilling should emphasize these two points.