红柳峡跨断层水准多次出现由张性背景转为大幅压缩的规律性变化，基于青藏高原地区5级以上地震高频时空分布特征，与祁连山断裂带异常跨断层场地同步性进行对比，结果显示：①红柳峡跨断层水准与祁连山断裂带上其他跨断层异常场地变化时间一致性较好；②在红柳峡水准出现压性变化的1年内，青藏高原5级以上地震高频活动多发，且红柳峡水准出现压缩变化时段内，在青藏高原内部多形成NE向5级以上地震条带，表明应力多沿NE向集中。研究结果表明，印度洋板块在北向推挤增强过程中，引发青藏高原内部及周边块体一系列地震，而作为祁连山断裂带西端特殊的跨断层场地，红柳峡跨断层存在块体调整过程中出现较为规律异常变化的可能。
The cross-fault level of Hongliuxia has changed from a tension to a large-scale compression. By comparing synchronicity of the anomalous cross-fault sites on Qilian mountain fault zone and the spatial and temporal distribution characteristics of the high frequency of earthquakes above magnitude 5 in the Qinghai-Tibet Plateau, the result shows that the changes of Hongliuxia cross-fault leveling have a good time consistency with other abnormal cross-fault sites in Qilian mountain fault zone. The high frequency activities of earthquakes above magnitude 5 in the Qinghai-Tibet Plateau mostly occurred within one year after the compression change of Hongliuxia. In the compression change period of Hongliuxia cross-fault leveling, North-East direction seismic belt is formed in the inner area of the Qinghai-Tibet Plateau. It indicates that the stress is concentrated along this direction, which causes the adjustment motion of the fault with the change of stress. It indicates that during the northward compression of the whole India ocean plate, a series of adjustments were made to the Qinghai-Tibet Plateau and its surrounding blocks. As a special fault at the west end of the Hongliuxia fault zone, it is possible that there will be some regular abnormal changes during the block adjustment.
2019,40(2): 83-90 收稿日期：2018-09-13
DOI：10.3969/j.issn.1003-3246.2019.02.011
基金项目：国家重点研发计划（项目编号：2018YFC0807000）；中国地震台网中心青年科技基金（项目编号：QNJJ201801）；2019年度震情跟踪定向工作任务（项目编号：2019010223）
作者简介：岳冲(1989-),男,助理研究员,主要从事跨断层数据分析及地球动力学研究工作。E-mail:dacongyue@126.com
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