鄂尔多斯盆地由垩系地下水形成分布规律

鄂尔多斯盆地是一个巨大的开启型自流水盆地。白垩系是其中含水最丰富的岩体，约有７．５７亿ｍ３／ａ天然水资源。这些资源以白垩系下部的宜君洛河含水岩组为主要载体，供水条件也最优越。大气降水是白垩系地下水的主要补给来源，并以盆地内部四条分水岭为高势能区，以五个河系为主要排水通道，向四周排泄。白垩系地下水主要蕴藏在盆地北部，并以淡水占优势；南部则以微咸──半咸水比较丰富。

FORMATION AND DISTRIBUTION OF THE GROUNDWATER IN CRETACEOUS SYSTEM OF THE ORDOS BASIN

The Ordos Basin is a huge artesian one,where Cretaceous System is richest in water, bearing about 757 million m3/a of water resources. The Yijunluohe Group under Cretacic ismain water carrier, favorable in water supply condition. The precipitation, the main make-up source, drains all around from the high potential area,4 divides in the basin, five river cannals become main drainnage way. The ground water in Cretacic is mainly distributed in the north part of the basin, fresh water constitutes the majority.But the south part is rich in salt water.