四川盆地海相碳酸盐岩储层特征及控制因素

四川盆地海相碳酸盐岩储层发育层系多、累计厚度大，在川渝地区天然气储量和产量贡献中占有重要地位。从岩石类型、物性特征、储层类型等基本特征分析入手，研究和总结了盆地内碳酸盐岩储层发育的主控因素和分布预测思路。盆地主要储集岩类型是颗粒白云岩、藻（礁）格架白云岩、粉-细晶白云岩，石灰岩次之;物性总体上具低孔、低渗的特征，局部地区发育的优质储层是重要的勘探对象;储层类型可分为裂缝-孔隙型、孔隙型、裂缝-孔洞型和裂缝型4类;储层发育程度主要受有利沉积相带分布、白云石化作用、3期岩溶作用等因素控制。针对生物礁、颗粒滩等相控型储层，精细沉积微相刻画是储层分布预测的有效手段;对于风化岩溶型储层，区域性和重点目标区的岩溶古地貌恢复可为成藏区带评价和储层预测提供依据。

The characteristics and development law of marine carbonate reservoirs in Sichuan Basin, China

Many carbonate reservoirs in Sichuan Basin have been developed in multi-strata and accumulated in large thickness. These carbonate reservoirs play a great role in natural gas reserves and production in Sichuan-Chongqing region. Based on the analysis of basic characteristics such as rock types, physical properties and reservoir types, this study summarized the main controlling factors of development of carbonate reservoirs and the prediction of reservoir distribution in Sichuan Basin. The main types of reservoir rocks are granular dolomite, algal (reef) dolomite, and powder-fine crystal dolomite, followed by limestone. The reservoir rocks are generally characterized by low porosity and low permeability. High-quality reservoirs developed in local areas are the favorable exploration zones. The reservoirs can be divided into four types, i.e., fractured-porous reservoir, porous reservoir, fractured-vuggy reservoir, and fractured reservoir. The degree of reservoir development is mainly controlled by multi-factor such as the favorable sedimentary facies, dolomitization, and three-stage dissolution. Detailed depiction of sedimentary microfacies is an effective way for prediction of reservoir distribution in facies-controlled reservoirs such as organic reefs and grain shoals. As for the karst reservoirs associated with weathering, reconstruction of regional and local palaeogeomorphology will provide a basis for reservoir evaluation and prediction.