Ancient landslide river damming event in the Batang fault zone, Tibetan Plateau

Several ancient landslides triggered by earthquakes have occurred on the eastern margin of the Tibetan Plateau. Certain evidence of these landslides blocking rivers is preserved, which provides a good geological carrier for studying historical tectonic activities and valley evolution processes. The Huang-Cao-Ping (HCP) landslide is an ancient river-damming landslide that occurred in Batang County, Sichuan Province, located in the Batang fault zone. This study combined remote sensing interpretation, field investigation, geological dating, and engineering geological analysis to examine the development characteristics, landslide formation mechanism, and the evolution process of the landslide dam. The study results showed that the HCP landslide was a large-scale Holocene rock landslide with a volume of 143 x 10(4) similar to 238 x 10(4) m(3) triggered by a strong earthquake. The landslide blocked the Baqu River, and the dam underwent two breaching stages. The landslide-dammed lake occurred at least 5930 years ago, and a complete dam breach occurred later than 950 a B.P. Further, the initial volume of the upstream inundation area of the dammed lake extended for 2.17 km, and the volume was approximately 124.2 x 10(4) m(3). Following the first burst of the landslide dam, the area of the dammed lake was approximately 5.2 x 10(4) m(2), and the volume of the upstream inundation area was approximately 47.3 x 10(4) m(3). These results are expected to provide a reference for studying similar rockslides and exhibit great significance for reconstructing the regional tectonic activity history.

Automated summary

It has been discovered that there is an ancient landslide called the Huang-Cao-Ping landslide in the Sichuan province of China, which was triggered by a strong earthquake and blocked the Baqu River, forming a landslide lake that was later breached. The study results are expected to be significant for the reconstruction of regional tectonic activity history and for the study of similar rockslides.