材料
Online ISSN : 1880-7488
Print ISSN : 0514-5163
ISSN-L : 0514-5163
論文
岩石残留磁化を用いた掘削コア試料の定方位化:半遠洋性堆積軟岩への適用例
杉本 達洋山本 裕二山本 由弦林 為人
著者情報
ジャーナル フリー

2020 年 69 巻 3 号 p. 256-262

詳細
抄録

In-situ orientations of drilled core samples are valuable for a broad area of geological and geophysical researches (e.g. the determination of in-situ principal stress directions or the analyses of geological structures). In many cases, however, the information on in-situ orientation of core samples is not available. In this paper, a method for restoring the in-situ orientation of drilled whole-round core samples and its application to hemipelagic ocean sedimentary rocks are presented. The method is based on natural remanent magnetization (NRM) of rocks. As a case study, we applied this method to the 15 oceanic sedimentary soft rock samples collected at the toe of the Nankai trough, SW Japan, during International Ocean Discovery Program (IODP) Expedition 370. We developed a new sample preparation procedure which enabled us to get more data and then to evaluate the NRM measurement results well. Some samples were not able to be reoriented due to magnetic overprints associated with the drilling operations. In order to evaluate the magnetic overprints caused by drilling operation and to assess the data quality of the core reorientation by this method, we propose an evaluating system including three ranks defined for the different levels in which NRM results were affected by drilling operations. This evaluating system could be useful to assess the data quality of core reorientation by NRM method in the other similar applications.

著者関連情報
© 2020 日本材料学会
前の記事 次の記事
feedback
Top