Monitoring and assessment of barrier lakes formed after the Wenchuan earthquake based on multitemporal remote sensing data

The Wenchuan earthquake on May 12, 2008, triggered many secondary disasters, among which the barrier lakes formed by landslides were extremely serious. We monitored the number and spatial distribution of the barrier lakes in the earthquake-hit area from ADS40 airborne images, which covered areas of about 23,700 km 2. The results showed that there were 51 barrier lakes in the monitored area; among these, 10 were large-scale lakes and 14 were middle-sized lakes. The barrier lakes were distributed along the Longmen Mountain fault from the northeast to southwest direction. We used the dimensionless blockage index (DBI) to assess the potential risk of the barrier lakes. A small DBI value indicated a stable barrier lake, but the lake might have a higher risk with potential accumulative secondary disasters. Our study emphasized the monitoring and analysis of the high-risk Tangjiashan Barrier Lake from the multitemporal ADS40 airborne images acquired on May 16, 19, 23, and 27. We found that the water level at this barrier lake reached 66 m within 15 days after the barrier lake was formed, and the reservoir storage capacity reached 1.2 × 10 8 m 3 with an increase of 8 × 10 6 m 3 of water per day. Therefore, it faced a very real and urgent risk of dam break and overflow, considering the predicted storm rainfall and the continuous aftershocks. According to the analysis results, airborne remote sensing demonstrated the advantages of being intelligent, being able to maneuver, and providing high resolution. These advantages allowed us to quickly monitor and assess the distribution and dynamic changes of the barrier lakes in the earthquake-hit region using multitemporal airborne remote sensing images.

[1]  John E. Costa,et al.  A Perspective on Landslide Dams , 1986 .

[2]  Oliver Korup,et al.  Geomorphometric characteristics of New Zealand landslide dams , 2004 .

[3]  Liu Bin-tao Investigation on Damming Object Induced by the Earthquake of Wenchuan on May 12 Based on Multi-platform Remote Sensing , 2008 .

[4]  C. F. Lee,et al.  The 1786 earthquake-triggered landslide dam and subsequent dam-break flood on the Dadu River, southwestern China - Reply: A short reply to discussion by Chanson. © 2005 Elsevier B.V. All rights reserved , 2005 .

[5]  Adrian Luckman,et al.  Early recognition of glacial lake hazards in the Himalaya using remote sensing datasets , 2007 .

[6]  Nicola Casagli,et al.  Prediction of the behaviour of landslide dams using a geomorphological dimensionless index , 2003 .

[7]  John Small,et al.  A modern dictionary of geography , 1986 .

[8]  John J. Clague,et al.  Non-commercial Research and Educational Use including without Limitation Use in Instruction at Your Institution, Sending It to Specific Colleagues That You Know, and Providing a Copy to Your Institution's Administrator. All Other Uses, Reproduction and Distribution, including without Limitation Comm , 2022 .

[9]  Zeng Yong Detection of Ecological Environment Around Longyongxia Reservoir, the Upper Reach of the Yellow River by Remote Sensing and GIS , 2003 .

[10]  Richard Stone Landslides, Flooding Pose Threats as Experts Survey Quake's Impact , 2008, Science.

[11]  Nicola Casagli,et al.  Geomorphic analysis of landslide dams in the Northern Apennine , 1999 .

[12]  John E. Costa,et al.  The formation and failure of natural dams , 1988 .

[13]  R. L. Schuster Landslide Dams-A Worldwide Phenomenon. , 1995 .