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在渭河盆地东南缘的华山山前断裂北侧,对分布于陕西华县莲花寺一带数平方千米的黄土之下松散堆积的角砾岩的成因存在多种不同的认识,笔者根据地貌和堆积物特征支持其为高速远程滑坡的观点,并确定滑坡分为早、晚两期,后期还叠加了崩塌。野外调查发现覆盖于滑坡体上的黄土最大厚度达9m,根据第四纪黄土平均堆积速率估算的年龄与前人认为的滑坡时代大相径庭。为了准确厘定陕西华县莲花寺滑坡的形成时代,对覆盖于滑坡体上的黄土进行了5个剖面的样品采集,应用光释光(OSL)方法开展了系统的测年,结果5个剖面角砾岩之上最底部的黄土年龄在130.2±5.6~187.3±7.7ka之间,显示角砾岩之上堆积的黄土并不是同时形成的,其堆积的先后可能与古地形有关,角砾岩之上最底部黄土的最老年龄(187.3±7.7ka)代表了陕西华县莲花寺第二次滑坡形成时代的上限,即陕西华县莲花寺高速远程滑坡至少形成于18.7万年前。这是首次准确获得陕西华县莲花寺古滑坡的时代上限,亦是目前国内报道最老的高速远程滑坡,对滑坡的研究具有重要意义。同时,讨论了华县莲花寺高速远程滑坡的诱因可能是华山山前断裂的地震活动。
On the north side of the Huashan piedmont fault in the southeastern margin of the Weihe River Basin, there are many different understandings on the genesis of loosely accumulated breccias distributed under the loess of Lianhua Temple in Huaxian County, Shaanxi Province. Based on the topography and the accumulation The characteristics of the object support its view of high-speed remote landslide, and determine that the landslide is divided into two phases of early and late phases, and the later phases also collapse. Field surveys found that the maximum thickness of loess covered on the landslide body was 9m, and the age estimated from the average accumulation rate of the Quaternary loess was quite different from what the predecessors thought of the landslide era. In order to accurately determine the formation age of the Lianhua Temple landslide in Huaxian, Shaanxi Province, samples of 5 loess sections covering the landslide body were collected and systematically measured by using OSL method. The loess at the bottom of the conglomerate is between 130.2 ± 5.6 ~ 187.3 ± 7.7 ka, indicating that the loess accumulated over the breccia is not formed at the same time. The accumulation of the loess may be related to the ancient terrain. The breccia The oldest age of the uppermost loess (187.3 ± 7.7 ka) represents the upper limit of the second landslide era in Lianhua Temple, Huaxian County, Shaanxi Province. The high-speed remote landslide at Lotus Temple in Huaxian County, Shaanxi Province, at least formed 187,000 years ago. This is the first time that an accurate upper limit of the ancient landslide of Lianhua Temple in Huaxian County in Shaanxi Province is obtained. It is also the oldest high-speed remote landslide reported in China at present, and it is of great significance for the study of landslides. At the same time, it is discussed that the inducement of high-speed remote landslide in Hua-hua Temple in Huaxian may be the seismic activity of Huashan piedmont fault.