Study on the Characteristics of Neogene Sandstone Thermal Reservoir in Xi 'an Depression

Abstract

Neogene sandstone thermal reservoir is widely developed in Xi 'an Depression, Guanzhong Basin, which is the most important thermal reservoir in this area. Based on the core and logging data of geothermal wells in Xianyang, Xi 'an, Zhouzhi and other areas in Xi 'an Depression, this paper systematically discusses the reservoir characteristics of Neogene sandstone thermal reservoirs in Xi 'an Depression, and also discusses the relationship between reservoir characteristics and water-yeilding capacity. The thermal reservoir is composed of fluvial-delta-lacustrine interactive sand and mudstone deposition, with positive rhythm characteristics. The reservoir rock is mainly feldspar lithic sandstone, and the reservoir space is dominated by dissolution pores and primary pores, with good porosity and permeability. The sand pushes inward from the south and east of the depression. Reservoir conditions affect the water-yeilding capacity of geothermal wells. The water yield of monolayer is mainly affected by physical property and argillaceous content. The lower the argillaceous content is, the better the physical property is, the higher the water yield of monolayer sand is.