| Summary: | application/pdf Crustal evolution and deep structure viewed from East Antarctic Shield are summarized relating to the continental growth process in the Earth's evolution. First, the crustal structure of Antarctica is discussed by comparing deep seismic probings of the other Precambrian continents. Next, seismic reflection/refraction carried out in Antarctica in recent few years are reviewed to obtain an insight into the tecnological development. In the latter chapters, we focused on the subsurface structure and the crustal evolution of the Luzow-Holm Complex (LHC), around Syowa Station (39°E, 69°S), East Antarctica. The ""Structure and Evolution of the East Antarctic Lithosphere (SEAL)"" project has been carried out from 1996-1997 austral summer season within the framework of the Japanese Antarctic Research Expedition (JARE). The main target of the ""SEAL geotransect"" is to obtain a whole crustal section in the different geological terrains from the Archean to the early-Paleozoic ages from Western Enderby Land to Eastern Queen Maud Land. In the austral summer season of 2000, deep seismic refraction/wide-angle reflection probing was conducted on an ice sheet in the northern Mizuho Plateau, of the LHC by JARE-41. More than 160 plant-type 2 Hz geophones were set along the Mizuho route 190 km in length. A total of 3,300 kg dynamite charge at seven sites along the route gave information concerning the deep structure of a continental margin of the LHC. Continental evolution from the Archean ages to the present are clarified by combining the geoscientific results from East Antarctic shield and those from the other cratonic terrains of the Earth's continent in future. departmental bulletin paper
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