A study on Transporting process of clastics under Kuroshio Extension.

黑潮延伸作用下碎屑搬运过程研究。

• 批准号: 16540424
• 负责人: KANAMATSU Toshiya
• 金额: $ 1.66万
• 依托单位: Japan Agency for Marine-Earth Science and Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16540424/
• 关键词: Kuroshio Extension; Kuroshio path change; Glacial; Interglacial; relative paleointensity of geomagnetism; Rock-magnetism; magnetic grain size; 黒潮続流; 大水深; 磁気特性; 相対地球磁場強度; 親潮; 粒度変化; 岩石磁気パラメーター

It is revealed that the rock-magnetic property of surface sediment under Kuroshio Extension is characterized by magnetite in magnetic mineralogy, and the high distribution in amount of magnetic mineral is recognized at 32-34゜N. In the condition which magnetic mineralogy is dominant in magnetite, the large magnetic grain size at 34-32゜N is observed, but the distal and southern sites involve the smaller magnetite. These spatial distributions of the grain size and amount of magnetite suggest that the clastic material of Izu-Ogasawara ridge, which including magnetic mineral, is spilled by the stream of Kuroshio Extension into the Northwest Pacific basin.The spatial and temporal distribution of the sediment character in the study area show the distinction in the chemical and rock-magnetic property between glacial and interglacial periods. At the maxima in glacial period, the magnetite contribution to the sediment component is small, the bulk chemical component shows less in Al and rich n Si. These patterns suggest the small supply of clastics, probably because the stream pattern of Kuroshio Extension was different from the current situation. In the interglacial glacial periods, 34゜N core shows the smaller change in grain size, on the other side, cores in southern and proximal sites shows that the grain size have changes unsteadily. The interpretation of the changes is that 34゜N core have been in axial zone of the Kuroshio Extension in constant, but the others have been in the margin of the Kuroshio Extension, and been susceptive to the change of Kuroshio Extension.The change of amount of magnetic mineral shows a high fluctuated pattern, and this pattern is very similar to the isotope data of the Greenland Ice-core.

结果表明，黑潮延伸带表层沉积物的岩石磁性以磁铁矿为特征，在32-34°N地区磁性矿物含量较高，处于磁性矿物学占主导地位的条件下。磁铁矿，在 34-32゜N 处观察到较大的磁性颗粒尺寸，但远端和南部站点涉及较小的磁铁矿，这些颗粒尺寸和磁铁矿数量的空间分布表明，伊豆-小笠原海脊的碎屑物质，其中包括磁性矿物，由黑潮伸展流溢入西北太平洋盆地。研究区沉积物特征的时空分布显示出化学和岩石磁性的区别。冰期和间冰期之间的性质在冰期最大时，磁铁矿对沉积物成分的贡献很小，大体化学成分显示出较少的Al和丰富的n Si。碎屑岩，可能是因为黑潮延伸段的水流模式与现在的情况不同，在间冰期，34°N 的岩心显示出颗粒尺寸的变化较小，而南部和近端地点的岩心显示出颗粒尺寸的变化。变化的解释是，34゜N核心一直处于黑潮延伸带的轴向区域，而其他核心则位于黑潮延伸带的边缘，磁性矿物量的变化呈现出高波动模式，这种模式与格陵兰冰芯的同位素数据非常相似。

项目成果

北太平洋海底コアに記録される第四紀中・後期のテフラ層序:広域テフラとの対比と年代モデルの構築

北太平洋洋底岩心记录的中晚第四纪火山灰地层：与区域火山灰的比较及年龄模型的构建

• 发表时间: 2006
• 期刊: 第四紀研究 45
• 作者: 菅沼悠介;青木かおり;金松敏也;山崎俊嗣
• 通讯作者: 山崎俊嗣

Tephrostratigraphy of deep-sea sediments in the northwestern Pacific and implication for chronology of the past 300 kyr

西北太平洋深海沉积地层学及其对过去300 kyr年代学的意义

• 发表时间: 2006
• 期刊: The Quaternary Res. (Dai-yonki Kenkyuu)(in Japanese with English abstract) 45
• 作者: Y.Suganuma;K.Aoki;T.Kanamatsu;T.Yamazaki
• 通讯作者: T.Yamazaki

Relative paleointensity stack during the last 250 kyr in the northwest Pacific

• DOI: 10.1029/2006jb004477
• 发表时间: 2007
• 期刊: Journal of Geophysical Research
• 作者: Y. Yamamoto;T. Yamazaki;T. Kanamatsu;Noboru Ioka;T. Mishima

北西太平洋海底コアに記録される第四紀中・後期のテフラ層序 : 広域テフラとの対比と年代モデルの構築

西北太平洋洋底岩芯记录的中晚第四纪火山灰地层：与区域火山灰的比较及年龄模型的构建

• 发表时间: 2006
• 期刊: 第四紀研究 45
• 作者: 菅沼悠介;青木かおり;金松敏也;山崎俊嗣
• 通讯作者: 山崎俊嗣