摘要
热水—日月山断裂带是青藏高原东北缘柴达木—祁连山活动地块内部一条重要的NNW向的右旋走滑活动断裂带.断裂活动形成了一系列山脊、冲沟和阶地等右旋断错微地貌及断层崖、断层陡坎等垂直断错微地貌.本文对发生在该断裂带上的古地震事件开展了研究,综合探槽剖面和断层陡坎年代,大致可以确定两次古地震事件,其年代分别为距今6280±120a,2220±360a,复发间隔约4000a左右.
Reishui-Riyue Mt. active fault zone is a very important NNW oriented rightlateral strikeslip active fault zone which developed in the Chaidam-Qilian Mt. active crustal block,northeastern margin of Qinghai-Tibet Plateau.The activity of the fault causes a series of microgeomorphologies,such as ridge, valley and terrace,rightlateral offseted and forms fault cliff and fault scarp et al. vertical offset microgeomorphology.In this paper,the palaeoearthquake events on the fault are studied.Combining the trench profiles and fault scarp measurement,two palasoearthquake events are determined,which occured in 6 280±120 a B.P. and 2 220±360 a B.P.,the recurrence interval is about 4 000 a.
引文
国家地震局兰州地震研究所 .青海黑泉水库地震安全性评价报告 . 1 994.
青海省地震局 .涩北—兰州输气管线地震安全性评价报告 . 1 999.
袁道阳 ,刘小龙 ,等 .青海热水—日月山断裂带的新活动特征 .地震地质 . 2 0 0 3 (待刊 ).
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