Reservoir Regulation for Control of an Ancient Landslide Reactivated by Water Level Fluctuations in Heishui River, China

Abstract

Due to the complex geological processes of Qinghai-Tibet Plateau, numerous deposits, especially the large-scale ancient landslide deposits, are characteristic features of the valleys incised in southwestern China. Intense water level fluctuations since 2011 in Maoergai Reservoir, China, registered the reactivation of Xierguazi ancient landslide, and presented a significant risk to neighboring facilities. Based on detailed field survey and drilling exploration, the landslide was divided into Zone A and Zone B, and other characterizations of landslide were studied as well. To precisely measure the extent of landslide displacement during filling and drawdown stage, surface displacement monitoring system was deployed on the landslide. The monitoring analyses data reveal that reservoir fluctuation is the dominant factor influencing landslide displacement, especially during drawdown stage. Moreover, a future sliding is anticipated in Zone A, while a creep had already existed in Zone B. A reservoir regulation was then established using the lead-lag correlation between reservoir fluctuation and landslide displacement and landslide stability analysis. In the end, the follow-up deformation monitoring demonstrates that the reservoir regulation controlled the landslide effectively. Landslide control by reservoir regulation in Maoergai can serve as a case study for other settlements involved in similar construction activities.

Keywords

ancient landslide / reactivation / reservoir regulation / displacement monitoring / correlation analysis

References

[1] Antonello G, Casagli N, Farina P, . Ground-Based SAR Interferometry for Monitoring Mass Movements. Landslides, 2004, 1(1): 21-28.

[2] Chang K T, Lin M L, Dong J J, . The Hungtsaiping Landslides: From Ancient to Recent. Landslides, 2012, 9(2): 205-214.

[3] Crosta G B, Agliardi F, Rivolta C, . Long-Term Evolution and Early Warning Strategies for Complex Rockslides by Real-Time Monitoring. Landslides, 2017, 14(5): 1615-1632.

[4] Dewitte O, Chung C J, Demoulin A. Reactivation Hazard Mapping for Ancient Landslides in West Belgium. Natural Hazards and Earth System Sciences, 2006, 6(4): 653-662.

[5] Dong G H, Zhang F Y, Ma M M, . Ancient Landslide-Dam Events in the Jishi Gorge, Upper Yellow River Valley, China. Quaternary Research, 2014, 81(3): 445-451.

[6] Ghiassian H, Ghareh S. Stability of Sandy Slopes under Seepage Conditions. Landslides, 2008, 5(4): 397-406.

[7] He K Q, Li X R, Yan X Q, . The Landslides in the Three Gorges Reservoir Region, China and the Effects of Water Storage and Rain on Their Stability. Environmental Geology, 2008, 55(1): 55-63.

[8] Hu X L, Tang H M, Li C D, . Stability of Huangtupo Riverside Slumping Mass II# under Water Level Fluctuation of Three Gorges Reservoir. Journal of Earth Science, 2012, 23(3): 326-334.

[9] Jiao Y Y, Wang Z H, Wang X Z, . Stability Assessment of an Ancient Landslide Crossed by Two Coal Mine Tunnels. Engineering Geology, 2013, 159: 36-44.

[10] Pánek T, Hradecký J, Šilhán K. Geomorphic Evidence of Ancient Catastrophic Flow Type Landslides in the Mid-Mountain Ridges of the Western Flysch Carpathian Mountains (Czech Republic). International Journal of Sediment Research, 2009, 24(1): 88-98.

[11] Pánek T, Hradecký J, Smolková V, . Giant Ancient Landslide in the Alma Water Gap (Crimean Mountains, Ukraine): Notes to the Predisposition, Structure, and Chronology. Landslides, 2008, 5(4): 367-378.

[12] Roth P R. Effective Measurements Using Digital Signal Analysis. IEEE Spectrum, 1971, 8(4): 62-70.

[13] Wasowski J, Bovenga F. Investigating Landslides and Unstable Slopes with Satellite Multi Temporal Interferometry: Current Issues and Future Perspectives. Engineering Geology, 2014, 174: 103-138.

[14] Yan L, Xu W Y, Wang H L, . Drainage Controls on the Donglingxing Landslide (China) Induced by Rainfall and Fluctuation in Reservoir Water Levels. Landslides, 2019, 16(8): 1583-1593.

[15] Yao W M, Li C D, Zuo Q J, . Spatiotemporal Deformation Characteristics and Triggering Factors of Baijiabao Landslide in Three Gorges Reservoir Region, China. Geomorphology, 2019, 343: 34-47.

[16] Yu S Y, Ren X H, Zhang J X, . Seepage, Deformation, and Stability Analysis of Sandy and Clay Slopes with Different Permeability Anisotropy Characteristics Affected by Reservoir Water Level Fluctuations. Water, 2020, 12(1): 201

[17] Zhao Y, Xu M, Guo J, . Accumulation Characteristics, Mechanism, and Identification of an Ancient Translational Landslide in China. Landslides, 2015, 12 6 1119-1130.

[18] Zhang Y G, Zhu S Y, Zhang W Q, . Analysis of Deformation Characteristics and Stability Mechanisms of Typical Landslide Mass Based on the Field Monitoring in the Three Gorges Reservoir, China. Journal of Earth System Science, 2019, 128 1 9