Formation mechanism of ecologites and the related high- and ultrahigh-pressure metamorphicrocks

对俯冲和碰撞构造背景下的榴辉岩及相关高压和超高压变质岩进行了地质学、岩石学和年代学研究。本文根据详细的野外地质填图，对以四国岛东部中部的别志地区和甲津地区为代表的古俯冲带的三八川变质带进行了研究。在构造地质、年代学、变质条件估计和P-T演化等方面做了细致的研究。苏鲁高压-超高压变质岩作为碰撞带变质带的代表，在中国也得到了广泛的研究。2001年9月，在日本四国的新滨市、土井、别西山召开了第六届国际生态学会议（第六届IEC），由本次研究的负责人高须明和研究员平岛孝雄主持。来自世界17个国家的120多名研究人员参加了会议。会议包括科学会议（3天）和在Besshi地区生态岩地点的实地讨论（2天），那里暴露了几种类型的生态岩。在会议上作了56次口头介绍和65次海报介绍。在会议上提出的重要论文和这项研究的一部分成果将发表在一份国际期刊上，特别是Lithos（Takasu，A.，Hirajima，T.和其他人（编辑）），现在正在进行最后的编辑，最近就要出来了。

Geological, petrological and geochronological research on eclogites and the related high- and ultrahigh-pressure metamorphic rocks from the subduction and collision tectonic settings has been done. The Sanbagawa metamorphic belt, especially in the Besshi district, central and Kotsu district, eastern Shikoku, as a representative of the metamorphic belt of an ancient subduction zone has been studied based on detailed field mapping. Precise studies on structural geology, geochronology, estimation of metamorphic conditions and P-T evolution have been done. The high- and ultrahigh-pressure metamorphic rocks in the Sulu belt in China have been also studied intensively as a representative of a collision zone metamorphic belt. The subsequent comparison of metamorphic process and exhumation mechanism among the subduction zone and the collision zone metamorphic rocks has been done at the final stage of this research.Akira Takasu of the head investigator and Takao Hirajima of an investigator of this research organized the Sixth International Eclogite Conference (6th IEC) held in Niihama, Doi and Bessiyama in Shikoku, Japan in September, 2001. More than 120 researchers were participated from 17 countries in the world. The conference included scientific session (3 days) and field discussion (2 days) at the ecologite localities in the Besshi district, where several types of ecologites are exposed. 56 oral and 65 poster presentations were done at the sessions. The important papers presented at the Conference and a part of the results of this research will be published in an international journal, special issue of Lithos (Takasu, A., Hirajima, T. and others (eds.)), now it is in the final editing procedure, and will be appeared very recently.