DESCRIPTION OF SUBMARINE ACTIVE FAULTS AROUND JAPANESE ISLANDS-A BASIC INVESTIGATION FOR SUBMERSIBLE SEISMOGEOLOGY-

日本列岛周边海底活动断层描述-潜水式地震地质基础调查-

基本信息

批准号：
06640577
负责人：
TAKEUCHI Akira
金额：
$ 1.41万
依托单位：
TOYAMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06640577/
关键词：
Plate boundary Active fault Research Submersible Seismogeology Tectonics Trench Tsunami Japanese Island arcs バクテリアマット

项目摘要

Results of the two years project for submarine seismogeology are summarized methodologically and tactically as follows :Since most active faults surrounding JapaneseIslands locate along boundaries between submarine ridges and basins similarly as on land, they can be roughly located if surface ship data of seismic profiling surveys are available. Direct observation of active faults on the bottom, however, is rather difficult because the more active faults tends to be buried easily by turbulent bottom current due to their own seismic activities. Not almighty but effective indicators used as markers in searching for submarine active faults are altered-color mats, including authigenic chemical deposits, bacterial mats, and fields of clam colonies. In addition, zones of fresh debris, ground fissures, brand-new fault scarplets which cut the recent sediments, fresh slickenlines on fault planes, and so on, are also available.Submarine co-seismic diastrophism in the northern epicenter area of t … More he 1993 South-western off Hokkaido earthquake was reported for the first time in the world. The report includes the new identifications of 1) "quake-rubble" characterized as autochtonous brecciation of unconsolidated mud layr and 2) "jump-fall rubble" scarcely distributed on the muddy flat-floor in front of steep scarps due to slope failure and/or landslide, which denote the strong motions during the main-shock and were visibly observed by submersible investigations.Seismotectonics along the eastern Nankai Trough werere-investigated on the basis of photographic analyzes of still-photos and video films recorded during the KAIKO and KAIKO-NANKAI programs, using structural indicators such as slip sense of fault, clastic dikes and joints. Tectonic stress orientation differs among the inner and outer tough slopes, indirectly indicating eastern motion of the Amurian plate (Enshu-nada deepsea terrace) and northward motion of the Philippine Sea plate (Zenisu Ridge). On the contrary, no such kind of stress zonation is found along the eastern maegin of Japan Sea, possibly because the plate boundary between the Amur and the Okhotsk plates are too immature. Less

在方法论和战术上总结了两年的潜艇地震学项目的结果，如下所示：由于围绕日占地的大多数主动断层沿着海底脊和鲈鱼之间的边界与土地相似，因此，如果可以使用地表船舶数据的地表船数据，则可以粗略地找到它们。但是，直接观察底部的主动故障是相当困难的，因为由于其自身的地震活动，由于湍流的底部电流而容易构建更活跃的断层。不是不规则的，但是用作寻找海底活性断层标记的有效指标是颜色垫子的改变，包括身份化学沉积物，细菌垫子和蛤菌群的田地。此外，还可以使用新鲜碎屑，地面裂缝，全新的故障猩红色，这些区域削减了最近的沉积物，在断层飞机上的新鲜Slickenlines等等。该报告包括1）新的标识，其特征为未经固结的泥浆的自动核酸质量和2）“跳跃瓦布尔”几乎不会在钢scrope岩的泥泞平坦地面上分布在斜坡上的斜坡上，这是由于斜坡故障和/或陆地滑坡而导致的，这在现有的投资中表明了在现有的，并在现有的投资中，在居住的情况下，均通过逐步进行了良好的投资。基于在Kaiko和Kaiko-Nankai程序中记录的静态和视频膜的摄影分析，进行了投资，使用了结构指标，例如缺点，经典的堤坝和关节。内部和外部硬插槽之间的构造应力取向有所不同，间接表明Amurian板块的东部运动（Enshu-Nada Deepsea Terrace）和菲律宾海板（Zenisu Ridge）的北向运动。相比之下，沿日本海的东部梅金没有发现这种应力分区，这可能是因为阿穆尔（Amur）和奥克霍特斯克（Okhotsk）板之间的板界太不成熟。较少的