西藏尼洋河多布水电站深厚覆盖层成因分析

ANALYSIS ON THE FORMING MECHANISM OF DEEP COVERING LAYER IN DUOBU HYDROPOWER STATION IN NIYANG RIVER IN TIBET

西藏尼洋河流域水能资源丰富,然而存在超300m厚度的覆盖层,探明深厚覆盖层的成因对开发水能资源有十分重要的意义。通过对多布水电站坝址深厚覆盖层进行钻探分析、物探解译和综合分析,发现青藏高原特殊的地质环境与气候变迁是多布水电站深厚覆盖层形成的直接原因。研究结果表明,尼洋河流域深厚覆盖层成因主要包含“气候型”加积型、河流冲积层、崩滑流加积层、堰塞湖相沉积、“构造型”加积层等5种类型。本文可为含深厚覆盖层地区水电工程选址和开发提供参考和指导。

The Niyang River basin in Tibet is rich in hydropower resources,however,covering layer with thickness of more than 300 m is widely distributed there.It is of great significance to investigate the causes of the deep covering layer for the development of hydropower resources.Detailed investigations are conducted to illustrate the forming mechanism of the deep covering layer of Duobu Hydropower Station,including drilling analysis,geophysical interpretation,and comprehensive analysis,and it is found that the special geological environment and climate change of the Qinghai-Tibet Plateau are the direct reasons for the formation of the deep overburden of Duobu Hydropower Station.In addition,the results show that the causes of deep overburden in Niyang River basin mainly include five types:“climate type”,river alluvial layer,collapse-slip-flow alluvial layer,barrier lake deposition,and“structure type”alluvial layer.This paper can provide reference and guidance for the site selection and development of hydropower projects in areas with deep overburden.