富县探区深盆气成藏特征与有利区评价

富县探区位于盆地的东南部，上古生界该区处于盆地南部生烃中心，气源条件较好；区内砂岩储层较为发育，具致密、低孔低渗的特点。初步的勘探结果表明本区上古生界普遍含气，且具有深盆气的基本成藏特点，地质评价认为，探区的东北部是上古生界天然气勘探的有利区。

Forming Characteristics of the Deep Basin Gas Reservoir and Evaluation of the Favorable Objectives in the Fuxian Exploration Region

Many gas fields with reserves over tens of billions of cubic meters recently have been found in the middle and north parts of the Ordos Basin. Characteristics of the reservoir have been showed as deep basin gas, in which the water bearing area is distributed in the high places around basin, while the gas bearing area is widely distributed in the middle of the basin. Fuxian exploration region is located in the south-east part of Ordos Basin. The region was in the center of south gas-generating kitchen of the basin during Upper Paleozoic deposition, which makes the region be in good supply of gas. The reservoirs in the region were fairly developed, but with sandstones being very tight and permeability and porosity very poor after severe diagenesis. Present exploration results have shown that reservoirs of Upper Paleozoic generally are gas-bearing and are of basic features of deep basin gas trap,which is the favorable objectives for gas exploration.