1億年前からの北西太平洋でのプレートの動き
"A plate reconstruction model of the NW Pacific region since 100 Ma"
Contents name: Dagik_NWPacific_100my Contents ID: L-25-1 図の出典 "Dynamics of Arc Migration and Amalgamation: Architectural Examples from the NW Pacific Margin" 著者 (1) Yasuto Itoh , (2) Osamu Takano and (3) Reishi Takashima 著者の所属 (1) Graduate School of Science, Osaka Prefecture University, Osaka, Japan
(2) Technical Division, Japan Petroleum Exploration Co. Ltd., Tokyo, Japan
(3) The Center for Academic Resources and Archives (Tohoku University Museum), Tohoku University, Sendai, Japan概要 A plate tectonic model of the northwestern Pacific region since 100 Ma is presented in this document. The evolution of the Pacific margin is viewed as a longstanding history of migration and amalgamation of allochthonous blocks onto the subduction zone. Such a process inevitably provoked diverse tectonic events. In order to reconcile paradoxical discrepancies in the docking process of arc fragments on the margin, the authors introduce a marginal sea plate with a spreading center that was alive in the Cretaceous. Oblique subduction of the ridge caused specific migratory igneous activity along the rim of the overriding plates, together with flips of shearing direction. Arc-trench systems upon the eastern and western sides of the marginal sea plate developed following different timelines and were eventually mixed up during the plate's closure that prompted formation of a coincident Oligocene clinounconformity widespread on the Eurasian margin. Since the demise of the hypothetical plate, the tectonic regime of the northwestern Pacific margin has been controlled by the growing processes, namely, the rotational history and modes of convergence of the Philippine Sea Plate. 詳しい説明 Web版ダジック・アース Dagik_NWPacific_100my