東アジアのジュラ紀付加コンプレックス(ジュラ紀付加体の地域地質と広域対比)(ジュラ紀付加体の起源と形成過程)  [in Japanese] Jurassic accretionary complexes in East Asia(Regional geology and correlation)(Origin and evolution of Jurassic accretionary complexes in Japan)  [in Japanese]

アジア-太平洋地域の地質構造発達史を復元するための基礎的な情報を提供するために, アジア大陸東縁に沿って分布するジュラ紀付加コンプレックスの岩相組合せ, 年代, 構造をレビューした.その結果, 北東端のコリャク高地から南は東南アジア, フィリピンに至る地域に, 途中で途切れながらも延々とジュラ紀付加体が分布することがわかった.これら付加体には, 共通して, 古生代後期の石灰岩-緑色岩複合岩体とペルム紀〜ジュラ紀の放散虫層状チャートが含まれる.これらの岩石はジュラ紀にユーラシア大陸縁辺部に沈み込んでいた海洋プレートの特徴(海洋プレート層序)を示している.チャートを覆う砕屑岩の年代やメランジュの基質の年代で示される沈み込みあるいは付加の年代は, ジュラ紀中世〜白亜紀古世とばらつきがあり, それは沈み込み・付加年代にある程度の空間的な差異があったことを示している.

Lithologic assemblages, ages, and structures of the Jurassic accretionary complexes along the eastern margin of Asia are reviewed in order to provide basic information in reconstructing plate tectonic evolution of the Asia-Pacific region.In the Koryak Highlands and Kamchatka Peninsula, most of the accretionary complexes are Cretaceous in age, althougth part of some terranes, such as the Talovskiy and Mainitskiy terranes, might include Jurassic accretionary complexes. The Sikhote-Alin Mountains is composed of accreted microcontinents with Precambrian basements, Mesozoic accretionary complexes, and Cretaceous basin-fill turbidite. Of these accretionary complexes, the Samarka terrane is Middle to Late Jurassic in age, and the Badzhal, Khabarovsk and Taukha terranes are of Jurassic to Early Cretaceous age. In Japan, including the Ryukyu Islands, many terranes consist of Jurassic accretionary complexes and their metamorphic equivalents, as discussed in other papers of this memoir. Terranes and suture zones in Southeast Asia are pre- or post-Jurassic in age, although the North Palawan block in the Philippines is a Jurassic accretionary complex.Most of the Jurassic accretionary complexes in East Asia have Late Paleozoic limestone-greenstone complex and Permian-Jurassic radiolarian bedded chert in common, which indicate characteristics of the oceanic plate subducted underneath the Eurasian continental margin in Jurassic time. Ages of the subduction and accretion indicated by the ages of clastic rocks covering the chert and/or the ages of matrix of melanges vary between Middle Jurassic and Early Cretaceous throughout the Asian margin. This means the regional variation of the ages of subduction and accretion.