Acoustic Surveys of Methane Plumes by Quantitative Echo Sounder in Japan Sea and the Estimate of the Seeping Amount of the Methane Hydrate Bubbles

DOI Web Site 13 Citations 33 References
  • AOYAMA Chiharu
    Japan's Independent Institute Co., Ltd.
  • MATSUMOTO Ryo
    Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo

Bibliographic Information

Other Title
  • 計量魚群探知機によるメタンプルームの観測とメタン運搬量の見積もり
  • ケイリョウ ギョグン タンチキ ニ ヨル メタンプルーム ノ カンソク ト メタン ウンパンリョウ ノ ミツモリ

Search this article

Abstract

 During methane hydrate exploration and research, remote and on-board acoustic surveying and monitoring of methane hydrate can be easily and economically conducted using a quantitative echo sounder. Simultaneously, the structure and the floating-up speed of methane plumes can be obtained from an analysis of acoustic data.<br> We conducted a survey of methane plumes from 2004 through 2008 at a spur situated southwest off the coast of Sado Island (tentatively called Umitaka Spur) and at the Joetsu Knoll. In 2007 and 2008, we performed experiments by releasing methane hydrate bubbles and methane hydrate, and letting them float upward. Consequently, we demonstrated that acoustical reflection from the methane plumes correlates with water temperature and depth, that the floating-up speed is constant but depends on the conditions of methane hydrate, that the discharge of methane hydrate bubbles changes, and that there is a wide scattering of materials below the seafloor where methane plumes are located. Furthermore, the amount of methane hydrate bubbles seeping was estimated by a preliminary calculation.<br> The method will be applied not only to basic research on methane hydrate but also to assessments of the environmental impact of methane hydrate exploitation.

Journal

Citations (13)*help

See more

References(33)*help

See more

Related Projects

See more

Keywords

Details 詳細情報について

Report a problem

Back to top