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中卫～同心活断层是香山北麓的区域性大断层,属于天祝～同心大断裂带的东段,长约150公里,由一系列长度不太大的不连续的雁列断层组成。1709年10月14日中卫南7 1/2级大地震就发生在该断裂带上,目前可以证实的破裂带已有64公里。该断裂带断错了晚更新世晚期以来的各个时期的地层。由横穿断层的一系列全新世冲沟的变位可知水平断距达25±3米,年平均滑动速率为2.5毫米。大约6000年以来,断层上共发生三次大地震,其平均复发周期为2299年。用微地貌法求得的平均重现间隔为2100年。
The Zhongwei ~ Concentric active fault is a regional fault in the northern foot of Xiangshan. It belongs to the eastern section of the Tianzhu ~ Tongxinda fault zone and is about 150 km long. It consists of a series of discontinuous geese faults that are not long in length. On October 14, 1709, a 7 1/2 magnitude earthquake hit Zhongnan South took place on the fault zone. At present, 64 km of rupture zone can be confirmed. The fault zone disrupted the strata of various periods since the Late Pleistocene. A series of Holocene gully transients that cross the fault show a horizontal offset of 25 ± 3 meters and an average annual glide rate of 2.5 mm. Three major earthquakes have occurred on the fault since about 6000 years, with an average recurrence period of 2299 years. The average reproducibility interval obtained by the micro-topography method is 2100 years.