塔河油田超埋深碳酸盐岩油藏基质的力学试验研究

Experimental Study of Matrix Mechanical Properties of Ultra Deep Carbonate Rock Oil Reservoir in Tahe Oilfield

碳酸盐岩油气藏在全球范围内分布广泛，其中30％以上为缝洞型碳酸盐岩油气藏。在我国缝洞型油藏占已探明的碳酸盐岩油藏储量的2／3，是今后增储的主要领域。为准确揭示碳酸盐岩油藏基质的力学特性，本文以塔河油田奥陶系油藏地层为研究背景，通过现场深孔钻井取样得到埋深达5300~6200m的碳酸盐岩油藏基质岩样，并通过力学试验首次获得超埋深碳酸盐岩油藏基质的弹模、泊松比、抗压强度、抗拉强度、粘聚力、内摩擦角等力学参数，借助电镜扫描试验揭示出超埋深碳酸盐岩的微细观破裂机制。该项研究成果可为分析碳酸盐岩油藏溶洞的垮塌破坏机理提供有效的试验参数。

Carbonate rock oil and gas reservoirs are widely distributed all over the world, among them, more than 300/00 are crack-cave type carbonate rock reservoirs. In our country, the proportion of crack- cave type oil reservoir is 2/3 of the proven carbonate rock oil reservoir, which is also the main increasing domain of oil storage in the future. In order to accurately reveal the mechanical properties of carbonate rock oil reservoir matrix, the ordovician oil reservoir stratum in Tahe oilfield was adopted as study background. Through spot deep hole drilling, carbonate rock oil reservoir matrix samples buried in underground depth of 5300 ~ 6200m were obtained. Mechanical parameters of ultra deep carbonate rock oil reservoir matrix, including elastic modulus, poisson＇s ratio, compressive strength, tensile strength, cohesion and angle of internal friction were obtained based on mechanical experiment. The micro fracture mechanism of ultra deep carbonate rock was revealed by electron microscope scanning. Above results may provide important experimental parameters for analyzing collapse failure mechanism of carbonate rock oil reservoir karst cave.