Quaternary Faulting in the Eastern Alaska Range
Quaternary Faulting in the Eastern Alaska Range
复制标题
阿拉斯加东部山脉的第四纪断层活动
DOI：
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发表时间：
1971
期刊：
影响因子：
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通讯作者：
N. A. Matson
中科院分区：
文献类型：
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作者：
D. Richter;N. A. Matson
在阿拉斯加山脉东部，沿德纳里断裂系统和新近发现的与之相关的托舒达断裂系统显示出较好的第四纪断裂作用。两个断层系统的主要运动都是右旋走滑。威斯康辛时代的冰川偏移特征表明，沿着迪纳里断裂系统的部分地区，全新世的最小滑动率为每年1.1至3.5厘米，沿着托舒达断裂系统，每年0.9至3.3厘米。沿迪纳里断裂系统的走滑运动可能不早于上新世早期，在托顺达断裂系统连接处东南部，可能在更新世中期结束。走滑toschunda断裂系统是一个更年轻的特征，可能不早于中更新世，表现出9至10公里的右侧偏移和1500米的相对垂直运动。托舒达断层系统与阿拉斯加湾的费尔韦瑟断层对齐，并具有相同的滑动感。迪纳利断层系统和夏洛特女王群岛断层是分隔北美板块和太平洋板块的主要转换断层系统的一部分。阿拉斯加南部大陆位于阿留申弧和德纳里断裂系统之间，现在大部分与太平洋板块相连。toschunda - fairweather走向可能代表了一条绕过迪纳里断裂系统东南部的新转换断层的开始。
Quaternary faulting is well displayed along the Denali fault system and the recently recognized and related Totschunda fault system in the eastern Alaska Range. The principal movement on both fault systems is right-lateral strike-slip. Offset glacial features of Wisconsin age indicate minimum Holocene slip rates of 1.1 to 3.5 cm per year along parts of the Denali fault system, and 0.9 to 3.3 cm per year along the Totschunda fault system. Strike-slip movement along the Denali fault system may be no older than early Pliocene and, southeast of the Totschunda fault system junction, may have terminated by the middle Pleistocene. The strike-slip Totschunda fault system, a much younger feature probably no older than middle Pleistocene, exhibits 9 to 10 km of right-lateral offset and 1,500 m of relative vertical movement. The Totschunda fault system is aligned with, and has the same sense of slip as, the Fairweather fault in the Gulf of Alaska. The Denali fault system and the Queen Charlotte Islands fault are part of a major transform fault system separating the North American and Pacific plates. Continental southern Alaska between the Aleutian arc and the Denali fault system is now largely coupled to the Pacific plate. The Totschunda-Fairweather alignment probably represents the beginning of a new transform fault by-passing the southeast part of the Denali fault system.