【摘要】 2008年汶川大地震引发了岷江流域映秀—茂县段极为严重的地震次生地质灾害。利用震后多期高分辨率航空遥感数据并结合解译标志,快速、准确地分析研究区灾害的分布规律及发展趋势,对科学指导灾后重建具有重要意义。次生地质灾害分布规律主要表现为:1滑坡、崩塌及其过渡类型——崩滑为主要的次生地质灾害类型(占90%以上);2次生地质灾害广泛分布在岷江两岸山坡,但在映秀—汶川段的发育程度和规模比汶川—茂县段大得多。研究区次生地质灾害发展趋势分析结果表明:1地震形成的滑坡体趋于稳定,但解译的21个潜在滑坡体中部分已出现活动迹象,其中斗簇和沏底关2个潜在滑坡群更为明显,应对其进行遥感连续动态监测;2泥石流为研究区今后最主要的灾害类型,其中映秀—汶川段为最主要的发生地段。更多还原

【Abstract】 The 2008 Wenchuan earthquak led to fatal secondary geological disasters in the Yingxiu-Maoxian segments along the Minjiang River. Through using multi-phase high-resolution airborne remote sensing data obtained after the earthquake in combination with interpretation signs of various geohazards,we can analyze the distribution regularity and development tendency of earthquake secondary geohazards quickly and accurately,which is of great significance in guiding reconstruction of the disaster area scientifically. The distribution regularity of secondary geohazards finds expression in the following aspects: 1 avalanche,landslide and landslide-avalanche( the transition type between the landslide and avalanche) constitute the main types,with landslide-avalanche taking up over 90%; 2 the geohazards are widely distributed on the both slopes of the Minjiang River in the Yingxiu-Maoxian segment,but their scales and intensities are much larger in the Yingxiu-Maoxian segment than in the Wenchuan-Maoxian segment. Through continuous dynamic monitoring of the secondary geohazards after the earthquake by using high-resolution aerial imagery acquired from 2009 to 2011 and in 2013,the authors have revealed that 25 earthquake-induced landslides have been stable basically,but some potential landslides( total21) show evident signs of activity,of which the Doucu potential landslides in Maoxian and Qidiguan potential landslides in Wenchuan deserve more attention. In addition,the debris flow will be the main geohazard type in the Yingxiu-Maoxian segment along the Minjiang River in the future; in the Yingxiu-Wenchuan segment,the frequency and intensity of the debris flow are especially obvious.更多还原