Quantitative assessment of deformation of upper crust based on paleomagnetism of widespread tephra and large-scale pyroclastic flow deposit
Quantitative assessment of deformation of upper crust based on paleomagnetism of widespread tephra and large-scale pyroclastic flow deposit
批准号:
17540438
负责人:
ITOH Yasuto
金额:
$2.24万
依托单位国家:
日本
项目类别:
Grant-in-Aid for Scientific Research (C)
财政年份:
2005
资助国家:
日本
项目状态:
已结题
起止时间:
2005 至 2006
中文摘要
本研究对日本本州岛中部广泛分布的火山灰、大规模火山碎屑流沉积和一座第四纪火山进行了野外调查。从39个地点获得了古地磁测量样品。通过旋转磁力计测量剩余磁化强度,并通过渐进热去磁和交流磁场去磁来评估剩余磁化强度的稳定性。为了估算岩石中的铁磁性矿物,采用脉冲磁化仪进行等温剩磁(reversization magnetization,简称reversization)的逐步采集,并通过正交磁化曲线的热退磁验证了估算结果。汇编了现有的场地平均古地磁方向,用于确定高应变区,该高应变区与最近通过全国GPS阵列的大地测量研究发现的变形区相关联。沿着这些研究,对1000万年以来的断裂运动和成盆历史进行了研究。通过对反射地震资料的解释,阐明了日本中部弧-弧结合带(北海道)和孕震俯冲带(日本东北部太平洋沿岸)的构造活动,为认识日本中部的构造提供了重要线索。利用古地磁方法对地壳短期形变进行了精确的估算,该方法通常用于研究板块间长期累积形变。
英文摘要
In this study, field survey was conducted for widespread tephra, large-scale pyroclastic flow deposits and a Quaternary volcano in the central part of Honshu Island, Japan. Samples for paleomagnetic measurements were obtained from 39 sites. Remanent magnetization was measured by a spinner magnetometer, and stability of remanence was evaluated by progressive thermal and alternating-field demagnetization. Progressive acquisition of isothermal remanent magnetization (IRM) was conducted using a pulse magnetizer in order to estimate ferromagnetic minerals in rocks, and the estimation was verified through thermal demagnetization of orthogonal IRM. Available site-mean paleomagnetic directions were compiled for determination of high strain area, which was correlated with a deformation zone recently detected through geodetic studies of nationwide GPS array. Along with these study, fault motion and basin-forming history over 10 m.y. in an arc-arc junction (Hokkaido) and a seismogenic subduction zone (Pacific coast of northeast Japan) were clarified on the basis of interpretation of reflection seismic data, which gave a significant clue to understand tectonics in central Japan. We have precisely assessed short-term crustal deformation utilizing paleomagnetic method, which is generally applied for long-standing cumulative deformation between plates.
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Integrated description of deformation modes in a sedimentary basin : A case study around a shallow drilling site in the Mizunami area, eastern part of southwest Japan
沉积盆地变形模式的综合描述:日本西南东部瑞浪地区浅层钻井现场的案例研究
DOI:
--
发表时间:
2006
期刊:
Island Arc 15
影响因子:
--
作者:
[Itoh, Y., Amano, K., Kumazaki, N]
通讯作者:
N
DOI:
10.1016/j.pepi.2006.02.009
发表时间:
2006-06
期刊:
Physics of the Earth and Planetary Interiors
影响因子:
2.3
作者:
[Y. Itoh;T. Tsuru]
通讯作者:
Y. Itoh;T. Tsuru
Evolution history of the Hidaka-oki (offshore Hidaka) basin in the southern central Hokkaido, as revealed by seismic interpretation, and related tectonic events in an adjacent collision zone
地震解释揭示的北海道中南部日高冲盆地的演化历史以及邻近碰撞带的相关构造事件
DOI:
--
发表时间:
2005
期刊:
Physics of the Earth and Planetary Interiors 153
影响因子:
--
作者:
[Itoh, Y., Tsuru, T.]
通讯作者:
T.
DOI:
10.1016/j.tecto.2004.09.003
发表时间:
2005-01
期刊:
Tectonophysics
影响因子:
2.9
作者:
[Y. Itoh;T. Ishiyama;Y. Nagasaki]
通讯作者:
Y. Itoh;T. Ishiyama;Y. Nagasaki
Evolution history of the Hidaka-oki (offshore Hidaka) basin in the southern central Hokkaido, as revealed by seismic interpretation, and related tectonic events in an adiacent collision zone
地震解释揭示的北海道中南部日高冲盆地的演化历史以及邻近碰撞带的相关构造事件
DOI:
--
发表时间:
2005
期刊:
Physics of the Earth and Planetary Interiors 153
影响因子:
--
作者:
[Itoh, Y., Tsuru, T.]
通讯作者:
T.
Quantitative assessment of the Quaternary tectonic movement based on paleomagnetism of widespread tephra and large-scale pyroclastic flow deposit
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批准号:15540440
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项目类别:Grant-in-Aid for Scientific Research (C)
-
资助金额:$1.92万
-
财政年份:2003
-
负责人:ITOH Yasuto
-
依托单位:
海外基金