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鄂尔多斯盆地中部奥陶系顶风化壳气藏是一负压气藏，气聚集在向东抬起大单斜的相对低部位。负压成因除与早白垩世后地壳抬升、生气速率减漫有关外，还主要由于储层饱含天然气，气藏中无自由水，上覆地层压力得不到有效地传递。流体势不仅与超压、浮力作用有关，还与地面高程密切相关。靖边－横山天然气藏的形成，为流体势所指示的气运移方向、风化壳孔洞发育带分布以及侧向古地貌隔挡诸因素的联合作用造成。
The Ordovician top-weather crust gas reservoir in the central Ordos Basin is a negative pressure gas reservoir, where the gas accumulates in the relatively lower part of the east of the large monocline. In addition to the correlation between negative pressure and uplift of crust and decrease of gas velocity after Early Cretaceous, it is mainly because the reservoir is full of natural gas and there is no free water in the reservoir, so the overburden pressure can not be effectively transmitted. Fluid potential is not only related to overpressure and buoyancy but also to ground elevation. The formation of the Jingbian-Yokoyama gas reservoir is caused by the combined effect of various factors such as the direction of gas migration indicated by fluid potential, the distribution of developmental pores in weathering crusts, and the isolation of lateral paleogeomorphics.