| 講演要旨(和文) | | 北海道天北西方沖で坑井掘削に関連し，浅部ガスポケットや特異な地質構造などのハザードを検出するためにサイトサーベイを実施した．そのうち、エアガン（GI Gun）を音源とする海上音波探査で取得した記録について、ハザードに対応したアノマリーを精度良く検出するために，相対振幅保存処理の最適化を図った．各種多重反射除去処理等のノイズ除去処理を慎重に実施し，サーフェス・コンシステント型振幅回復の処理ステップを工夫した．その結果，特に浅部ガスポケットなどハザードの存否の解釈を改善することができた. |
|
|
| | 講演要旨(英文) | | A site survey was carried out to investigate potential drilling hazards such as shallow gas pockets and anomalous geological structures in the Hokkaido Tenpoku Seiho Oki. The marine acoustic multichannel data acquired with airgun (GI gun) were essential information in the investigation and optimized relative amplitude preserving processing was carefully applied to the data in order to accurately detect anomalies related to the hazards. The processing includes various noise removals such as different kinds of multiple suppression and surface consistent amplitude recovery even for the marine data. As a result, the detectability of the anomalies, especially related to shallow gas pockets, could be improved significantly. |
|
|
|
| |
|