库车坳陷克深2气藏裂缝-孔隙型砂岩储层地质建模方法

目前，针对低渗透或致密裂缝-孔隙型砂岩储层的地质建模多局限于定性或半定量研究，通常的做法是将裂缝当做基质渗透率的增加因素来考虑，因而无法体现裂缝发育的方向性、不均一性，也无法描述连续合理的变化趋势。为此，针对塔里木盆地库车坳陷克深2气藏储集层为低孔隙度、低渗透率裂缝-孔隙型砂岩的实际情况，提出了一套将地质、地震、测井等手段综合一体化的裂缝-孔隙型砂岩储层地质建模方法。该方法首先利用地震、测井、岩心以及野外露头数据，以区内夹层分布为切入点建立岩性模型，并进行相控参数建模；再通过构造曲率法对该区裂缝的发育区带进行预测，并用其约束裂缝参数建模，从而建立了克深2气藏裂缝性砂岩储层的三维地质模型。实际运用效果证明，该方法所建模型符合地质认识规律，可量化储层参数，适用于裂缝-孔隙型油气藏评价阶段稀井网条件下的地质建模研究。

Geologic modeling of fractured and porous sandstone reservoirs in the Keshen-2 gas pool of the Kuqa Depression,Tarim Basin

At present, the geologic modeling of low permeability or tight fractured and porous sandstone reservoirs is qualitative or semi quantitative in nature. Generally, the fractures are regarded as a factor of enhancing matrix permeability, thus neither their orientation, heterogeneity nor their continuous variation can be rationally integrated in the model. As the reservoirs in the Keshen 2 gas pool of the Kuqa Depression, Tarim Basin, are fractured and porous sandstones with low permeability and low porosity, a comprehensive modeling method with geologic, seismic and logging data integrated is proposed for this type of sandstone reservoirs with dual porosity system. First, by use of seismic, logging, core and outcrop observation data, a lithologic model is built according to the distribution of interbeds in the study area, and the facies controlled petrophysical parameter modeling is performed. Then, the structure curvature method is used to predict the distribution of fractures, and the fracture parameters constrained are identified in modeling. Finally, a 3D geologic model is built for the sandstone reservoirs in the Keshen 2 gas pool. Results of field application show that models built with this method can reveal the real geologic conditions, quantify reservoir parameters, and will be used to evaluate the fractured and porous reservoirs with sparse well spacing.