日本地球惑星科学連合2018年大会

講演情報

[EE] 口頭発表

セッション記号 S (固体地球科学) » S-CG 固体地球科学複合領域・一般

[S-CG54] ハードロック掘削 オマーンから海洋リソスフェア,島弧形成+

2018年5月21日(月) 15:30 〜 17:00 A09 (東京ベイ幕張ホール)

コンビーナ:高澤 栄一(新潟大学理学部地質科学科)、道林 克禎(名古屋大学大学院環境学研究科地球環境科学専攻地質・地球生物学講座岩石鉱物学研究室)、Peter B Kelemen (共同)、Damon A H Teagle (Ocean & Earth Science, National Oceanography Centre Southampton, University of Southampton, SO14-3ZH, Southampton, UK)、座長:道林 克禎阿部 なつ江(海洋研究開発機構 海洋掘削科学研究開発センター)

16:45 〜 17:00

[SCG54-16] Advanced Well Logging across Crust-Mantle Transition in Oman

★Invited Papers

*KYAW MOE1Yasuhiro Yamada1Saneatsu Saito1Kazuya Shiraishi1Adam Wspanialy1Yoshihiko Tamura1Eiichi TAKAZAWA2Oman Drilling Project Phase II Science Party (1.Japan Agency for Marine-Earth Science and Technology, Center for Ocean Drilling Science、2.Department of Geology, Faculty of Science, Niigata University)

キーワード:Oman Drilling Project, Crust-Mantle Boundary, Well Logging, ICDP

To clarify the mohole discontinuity which was first identified in 1909 as step in the velocity of the seismic wave, it is necessary to drill and sample across crustal-mantle transition and that was original idea of the scientific ocean drilling more than four decades ago. This study is aiming to maximize the understanding on the petrophysical, geophysical, petrological and chemical nature across crustal-mantle transition, and to support in realistic planning for D/V Chikyu drilling and sampling fresh mantle in the future.

Under the International Continental Drilling Program (ICDP) support and guidelines, core samples from the crust-mantle (CM) boundary were taken in the Phase II (Nov., 2017-Jan., 2018). In addition, drilling parameters were monitored and recorded from two CM sites with cooperation from the drilling companies, and most advanced well logging was carried out to the depths where logging tools could reach.

Schlumberger’s wireline logging acquired high-resolution and continuous density-porosity, natural and spectral gamma, resistivity and its images, sonic velosity (P & S waves), and geochemical logs (elements and minerals). Preliminary results of acquired and processed well logging data across crust-mantle transition will be presented and plan for the data integration studies will be discussed. As first ever geophysical site survey taken from one of three offshore Mohole targets recently, potential application of Oman study results in the planning offshore Mohole to Mantle drilling (M2M) will also be introduced.