苏里格气田苏53区块南部地区有效砂体预测

鄂尔多斯盆地苏里格气田苏53区块勘探开发的主力层位为下二叠统石盒子组8段和下二叠统山西组1段，为确定该区块总体低渗透背景下相对高渗透储集砂体的分布规律、优选出天然气相对富集区，在综合利用气藏勘探、开发过程中获得的地震、地质、测井、钻井以及开发动态资料的基础上，应用相控条件随机模拟方法建立了定量的储层地质模型（包括单砂体模型和物性参数模型，其中物性参数模型又包括孔隙度模型、渗透率模型和含气饱和度模型），对该区块南部地区大面积低渗透、低丰度背景下有效储集砂体的展布规律及井间储层参数进行了预测。结果表明：①该区块有效储层主要分布在中南部和西部，以低孔隙度、低渗透率储层为主，其分布受沉积相控制明显，以河道砂为主的有效储层孔隙度明显高于其他岩性储层；②相对高孔隙度、高渗透率储层在侧向上和纵向均被相对低孔隙度、低渗透率储层所分隔，孔隙度、渗透率井间差异较大。

Mapping of the effective sandstone reservoirs in southern Block Su-53,Sulige Gas Field, Ordos Basin

The major targets of Block Su 53 in the Sulige Gas Field, Ordos Basin, are the 8^th member of the Lower Permian Shihezi Fm and the 1^st member of the Lower Permian Shanxi Fm. In order to understand the distribution patterns of the sandstone reservoirs with relatively high permeability in an overall low permeability setting of Block Su 53 in this gas field and predict target areas with relatively high gas potential, we made an integrated analysis of various available data, including seismic, geologic, logging, drilling and well performance data obtained during gas exploration and development. On this basis, the facies controlled conditional stochastic simulation method was used to build quantitative reservoir geologic models such as single sandbody models and physical property parameter models, the latter of which include the porosity model, permeability model and gas saturation model. These models were run to predict the distribution patterns of effective sandstone reservoirs and the inter well reservoir parameters in the southern Block Su 53 with overall low permeability and low reserve abundance. The following conclusions were obtained. (1) The effective reservoirs in the study area are mainly distributed in the south central and western parts of the block and are mostly of low porosity and low permeability reservoirs. Their distribution is significantly controlled by sedimentary facies. The effective reservoirs predominantly of channel sands have remarkably higher porosity than the other reservoirs of different lithologies. (2) The reservoirs with relatively high porosity and permeability are separated both laterally and vertically by reservoirs with relatively low porosity and permeability, resulting in large interwell variations of porosity and permeability.