| 講演要旨(和文) | | 各種物理探査法を複合的に適用し，断層構造を様々なスケールで連続的に，そして複眼的にイメージングすることを目標に研究プロジェクトを実施した．本報告では埼玉県北部の櫛挽断層を対象に2つのエリアで実施した浅部反射法地震探査の結果を報告する．対象エリア1のP波断面では地表撓曲崖下の深度10m〜80m付近に反射面の顕著な変形が認められ，この変形は断層に起因するものと考えられる．地表撓曲崖より北東側には北東に傾斜する連続のよい反射面が捉えられた．エリア2のS波断面では深度数mから10数mという極浅部で連続的なイベントが認められた．これらイベントは測線に近接する深度数m〜10mのトレンチ調査や群列ボーリングのデータと対比し得る深度である． |
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| | 講演要旨(英文) | | We have done a research about an integrated approach using various geophysical techniques for active fault investigations in multiple scale under the research contract with the Japan Nuclear Energy Safety Organization (JNES). It is expected that the application of various geophysical techniques can delineate images of active fault on multiple scale, from shallow to deep, and in various physical views. This is a subsequent report in the FY2010. We applied seismic reflection methods at Site 1 and Site 2 of the Kushibiki fault, Saitama Prefecture. At Site 1, unconformities and northeast dipping reflector are clearly imaged ten meter to hundred meter deep in the P wave section and they are also perceived on the shallower S wave section. At Site 2, continuous reflectors are poor in the shallower part of the P wave section, but several coherent events can be interpreted in the S wave section by comparison with arrayed borehole survey and trench survey. |
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