河西走廊深层地下水的赋存和开发

根据已有研究成果和勘探资料,将河西走廊深层地下水划分为早古生界、石炭系—二叠系、三叠系—侏罗系、白垩系—古近系、新近系—第四系下更新统5个层状含水岩组,分别论述了不同含水层的地质构造、岩性、厚度、分布规律、埋藏特征、富水性、地热及水文地球化学特征.重点研究了新近系—第四系下更新统含水层的地质结构和水文地质条件,自南而北将该含水层划分为山麓褶皱带、中央向斜带、单斜带三个贮水构造带.认为深层地下水的补给来源为上游祁连山区水文切割网基准面以下的基岩裂隙水,在地形和重力作用下,通过区域深大水资源循环系统,将山区地下水输送至盆地深部,但由于水循环深度达几千米甚至几十千米,径流十分缓慢,深部地下水的补给年龄可能大于1000a,并在白垩系、古近系和新近系中形成地热,取水温度一般可达60～70℃,预计单井出水量500～800m3/d.

Occurrence and Development of Deep Underground Water in Hexi Corridor

To the available acievements and exploration data,w divide underground water of Hexi corridor into five stratiform water-bearing rock group,which are Early Palaeozoic group,Carbo niferous-Permian, Triassic-Jurassic,Cretaceous-old Tertiary,and new Tertiary-down pleist ocene series of Quaternary, discussed different aquifers'geological structure,rock character,depth,regularities of distribution,bury character,water abundance,and hydrogeo-chemistry character for each.In addition,we analyzed the geological framework and hydrogeologic condition of the aquifers belong to new Tertiary-down Pleisto ceneseries of Quaternary,divided the aquifer into piedm ont fold zone,middle incline zone,and monocline zone three water-storedtect onic zone,from south to north.So we hold that the supply of the deep groundwater is from the water in the shelf crevice which under the hydrological cutting net of Qilianshan mountainous district.Because the effect of the to pograph and the gravitation,according to the large and deep groundwater circulatory system,the groundwater is transported to the deep part of the basin.However, because the water circulatory system's depth is more than thousands of meters even more dozens of kilometers,the ground water flows slowly,the age of the deep groundwater's supply may keep 800-1 000 years.In the Cretaceous,old Tertiary and new Tertiary-down pleistocene forms the geotherm,making the water tem perature reach 60-70℃ and the water out put of a single well reach 500-800m3/d.