SGER: Geomorphic Consequences of the 28 March, 1999, Garhwal Earthquake, Northern India

1999年3月28日，印度北部发生了里氏6.6级地震，震源集中在喜马拉雅山脉下面。1991年，在这次地震的100公里范围内发生过一次类似的地震。这导致了200多个斜坡的破坏，产生了相当于约0.007毫米的景观净下降。这比假定的喜马拉雅地貌每年下降的幅度要低几个数量级。1991年的研究对高震级-低频率过程在喜马拉雅景观演变中的重要性提出了质疑，并提出最有效的景观变化是低震级-高频率过程（如风化和河流侵蚀）的结果。关于大地震对喜马拉雅山内景观演变的影响的研究很少，因此很难评估1991年的地震是否典型。因此，我们建议研究1999年地震的地貌后果，并将其与1991年地震的影响进行比较。这项研究将有助于测试大地震在喜马拉雅景观的净剥蚀中是否重要，它也将有助于减轻灾害。

On March 28, 1999, an earthquake of magnitude 6.6 (Ms) shook Northern India, focused beneath the Garwhal Himalaya. A similar earthquake occurred in 1991 within 100 km of this recent earthquake. This resulted in over 200 slopes failures, producing an equivalent net lowering of the landscape of ~ 0.007 mm. This is several orders of magnitude lower than the assumed annual lowering of Himalayan landscapes. The 1991 study questioned the importance of high magnitude-lower frequency processes in the evolution of Himalayan landscapes and suggested that most effective landscape changes are the result of low magnitude-high frequency processes such as weathering and fluvial erosion. Few studies have been undertaken on the effects of great earthquake on landscape evolution within the Himalayas and it is therefore difficult to assess if the 1991 earthquake was typical. We, therefore, propose to examine the geomorphic consequences of the 1999 earthquake and to compare this with the effects of the 1991 earthquake. This study will help test if great earthquakes are important in the net denudation of Himalyan landscapes and it will also aid in hazard mitigation.