摘要
利用遥感手段,结合MapGis,研究了喜马拉雅山东南地区地质灾害的发育情况,发现本区发育的主要地质灾害有滑坡、崩塌、泥石流、冰湖以及堰塞湖.其中崩塌、滑坡、泥石流斜坡地质灾害是本区最重要的地质灾害类型,占到总灾害数量的95.3%.在此基础上对喜马拉雅山东南地区地质灾害发育规律初步研究,发现本区地质灾害的发育在空间上的分布并非均匀,而是具有丛集性的特点.滑坡灾害主要发育在隆子和朗县.泥石流灾害比较严重的有米林、隆子和洛扎3县,而崩塌则主要集中在隆子县.研究发现,本区滑坡发育与地层、地形坡度以及土地类型关系密切,其中修康群、日当组和念青唐古拉群是本区的'易滑地层'.涅如组由于面积大,其中发育的滑坡较多,但是滑坡的发育率只略高于本区的平均水平.统计表明,16°～30°的坡度范围是滑坡最容易发生的.大于45°以上的坡段很少发生滑坡.灌木林和天然草地这两种土地类型滑坡发育率最高.对于泥石流,研究表明,涅如组中泥石流发育面积最大,发育率也最高.泥石流发育的最适宜坡度也是16°～30°这样一个坡度范围.冰川和永久积雪区则最易发生泥石流.崩塌发育与地层类型、坡度的关系较为密切,崩塌主要发育在涅如组中,并且集中在坡度大于60°以上的陡坡段中.这些初步成果的取得,是以后进行该区地质灾害空间预测的基础.
Combined with RS and MAPGIS, the geohazards of the southeast of Himalaya Mountains in Tibet are studied. The geohazards include landslide, rock fall, mudflow, ice lake, and checked-up lake. The landslide, rock fall and mudflow account for about 95.3% of the total geohazards. The patterns of the development of geohazards are discussed accordingly. The results indicate that the geohazards are not evenly distributed in the region. A majority of the landslides are developed in Longzi county and Lang County. A majority of the mudflows are developed in Milin county, Longzi county and Luozha county. A majority of the rock falls took place in Longzi county. Meanwhile, the study shows that the landslides have a close relationship with the strata, the slope and the land type. The Xiukang group, Ridang formation and Nianqingtanggula group are prone to slide strata. The slope angle between 16°~30° is the slope angle prone to slide. and The shrubbery and grassland are the two land types prone to slide. The Niuru formation is the stratum prone to take place mudflow. The range of 16°~30° is the slope angle prone to mudflow too. The icefall and permanent snow area are the place easy to take place mudflow. However, the rock fall mainly takes place in the Nieru formation and on the slopes with slope angle larger than 60o. These findings can be used as a basis for a spatial prediction of the geohazards in the region.
出处
《工程地质学报》
CSCD
2007年第6期721-729,共9页
Journal of Engineering Geology
关键词
地质灾害
地理信息系统
滑坡
泥石流
崩塌
西藏
Geohazards, GIS, Landslide, Mudflow, Rock fall, Tibet, Himalaya mountains
作者简介
童立强,主要从事遥感工程地质工作.Email:qishengwen@mail.iggcas.ac.cn
