岩石物理相分类与油层有效厚度研究——以HQ地区长6特低渗透储层评价为例

PETROPHYSICAL FACI. FACIES CLASSIFICATION AND STUDY OF EFFECTIVE PAY THICKNESSES THICKNESS——TAKING THE EVALUATION OF CHANGTAKING CHANG 6 ULTRA-LOW PERMEABILITY RESERVOIRS IN HQ AREA AS AN EXAMPLE

针对长庆油田HQ地区长6储层受多期沉积、成岩作用及构造等因素影响,油层处于低孔、特低渗、复杂岩性、复杂孔隙结构储层中,储层储集性能和渗流结构差异大,测井响应复杂的特点,利用岩石物理相分类确定特低渗透油层有效厚度。通过油区各类测井、岩心和试油资料,研究评价岩石物理相的多种信息、划分方法及其分类评价。特别是开展了储层含油性、物性和电性关系分析,基于岩石物理相分类建立起特低渗透油层有效厚度下限标准,阐明了分类确定的参数下限变化表达出不同类别岩石物理相油层有效厚度下限差异及特征,避免了测井评价中有效储能和产能丢失。并以实例分析提取特低渗储层岩石物理相分类测井表征参数,实现了将非均质、非线性问题转化为相对均质、线性问题解决,提高了测井精细评价解释油层有效厚度的精度和效果。

The reservoir of HQ are in Changqing oilfield, located in the formation which is low porosity, low-permeability, complex lithology and complicated pore structure, is influenced by multi-period sedimentary, diagenesis and structrue. It is featured by complex logging response related to reservoir and difference heading from reservior storage and seepage structure. The effective thickness of low-permeability reservior can be determined by the use of petrophysical facies classification in the area based on the analysis of all kinds of logging core analysis data and formation test.Considering relationship and categorization features, the lower limit standards for ultra-low permeability effective pay thickness are established which give out the difference and characteristics between different petrophyical facies. They can avoid effective stored energy and productive capacity missed in logging evaluation.With the help of example analysis, anisotropic and nonlinear problems can be changed into relatively isotropical and linear ones, which improves the precision and effect of fine logging evaluation and interpretation.