Vertical crustal movements Kyushu during the past about 130 thousand years that utilized upper limit of the marine formations at the Shimosueyoshi Period as a standard of the displacement

以下末吉时代海相上限为位移标准的九州近13万年的地壳垂直运动

• 批准号: 08640577
• 负责人: SHIMOYMA Shoichi
• 金额: $ 1.34万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08640577/
• 关键词: Shimosueyoshi period (Stage 5e); Height of ancient shorelines; Crustal movements; Tephrostratigraphy; Paleodepth; Fossil shells; Trace Fossils; 生痕層序; 海面昇降

Data from the ancient shorelines along the present-day coastline of Kyushu Island, Western Japan, show that the island can be divided into several regions on the basis of modes of vertical crustal movements during the past 125,000 years. The heights of the ancient shorelines have been dectermined using paleodepth indicators such as molluscan faunas, trace fossils and sedimentary structures. The chronology of the sediments and of the tectonic events have been deduced from the well-documented history of volcanic ash events (tePhrostratigraphy) of southern Japan.The difference between the most uplifted and subsided areas in the island during the past 125,000 years is about l90 meters. Although it was previously thought that the whole of Kyushu Island was an uplifting region throughout this time, the present work has shown that there were marked differential movemcnts. North and south west Kyushu Were steadily subsiding areas, but rapid uplift occurred locally in the southern part of the island. A subsiding axis (the Saeki-Sendai Subsiding Axis) crosses the island with a NE-SW trend, and an E-W trending structural depression (the Beppu-Shimabara Graben) is present in central Kyushu.There is a clear correlation between the present-day coastal landform of the island and the differential tectonic movements that have occurred during the past l25,000 years.

日本西部九州岛现今海岸线沿线的古海岸线沿着的数据表明，根据过去12.5万年来地壳垂直运动的模式，可以将九州岛划分为几个区域。古海岸线的高度已确定使用古深度指标，如软体动物群，遗迹化石和沉积结构。根据日本南部火山灰事件（火山地层学）的历史资料，推断出沉积物和构造事件的年代学，在过去的125，000年中，岛上最大的隆起区和最大的沉降区之间的差异约为190米。虽然以前认为整个九州岛在这段时间里都是一个隆起的地区，但目前的工作表明，有明显的差异运动。九州西北部和西南部是稳定的沉降区，但在岛屿南部局部地区发生了快速隆起。在九州中部有一个东北-西南走向的沉降轴（佐岐-仙台沉降轴）穿过岛屿，在九州中部有一个东西走向的构造洼地（别府-岛原地堑）。