碳酸盐岩缝洞型油藏储层物性参数建模研究

Carbonate fracture-cavity reservoirs have various types of reservoir space and multiple porosity media structure. Because the evident difference of storage and permeability ability among different types of reservoirs, reservoir physical parameter distribution and variation are extremely complex, and space description and quantitative characterization are especially difficult, it has not formed mature method and simulation algorithm of property parameter modeling. At the section developing fractures and cavities of the reservoirs, drilling tool falling and drill mud leakage causes cores, well logs and other borehole data missing. So, it’s difficult to obtain the exact borehole datas, and the physical parameter model from these datas is low accuracy and reliability. This topic chooses Ordovician carbonate fracture-cavity reservoir of Tarim Basin as an experimental area, and focus on the following studies. First, the project team will carry out the logging evaluation of reservoir physical parameter for carbonate fracture-cavity reservoir, especially the large cave reservoir, and the reliable porosity and permeability datas will be obtained as hard datas of the physical parameter modeling. Second, the project team will develop a random simulation algorithm base on collaborative mathematical method, integrate seismic attribute data as modeling covariate to constrain crosswell physical parameter simulation. Third, according to the modeling method based on “physical parameter modeling controlled by fracture-cavity discrete distributed model”, the physical parameter models are established under the constraint of the facies controlled model and modeling covariate. Finally, a credible research method for physical parameter modeling of carbonate fracture-cavity reservoirs is proposed.

碳酸盐岩缝洞型油藏储集空间类型多样，不同类型储集体的储渗性能差异悬殊，储层物性分布及变化规律极其复杂，空间描述及定量刻画尤为困难，至今仍未形成较成熟的储层物性参数建模方法和模拟算法。此外该类储层缝洞发育部位常伴随钻具放空及泥浆漏失，造成岩心、测井曲线等井孔资料缺失，难以获取连续、准确的井孔确定性数据，建模获得的储层物性参数模型精度较低。本课题以塔里木盆地奥陶系碳酸盐岩缝洞型油藏为例，开展以下研究工作。一、针对性开展缝洞型储层，尤其是大型溶洞储集体物性参数测井定量评价研究，提供可靠的单井孔隙度、渗透率数据作为建模硬数据；二、开发基于协同型数学方法的建模算法，整合优选地震属性数据作为建模协变量，约束物性参数井间模拟；三、依据“缝洞离散分布相控”的建模思路，在相控几何形态模型和建模协变量的双重约束下建立储层物性参数模型。最终建立一套理论上可信、应用中可行的缝洞型油藏储层物性参数建模思路和方法。

碳酸盐岩缝洞型油藏储集空间类型多样，具有多重孔隙介质结构特征，不同类型储集体的储、渗性能差异悬殊，储层物性分布及变化规律极其复杂，空间描述及定量刻画尤为困难，至今仍未形成较成熟的储层物性参数建模思路和方法。加之该类储层缝洞发育部位常发生钻具放空和泥浆漏失，造成岩心、测井曲线等井孔资料缺失，难以获取连续、准确的井孔确定性数据，由此建立的储层物性参数模型精度较低、可靠性不高。.本课题以塔里木盆地奥陶系碳酸盐岩缝洞型油藏为例，开展并完成了以下研究内容。一、单井储层物性参数测井评价。针对性开展缝洞型储层，尤其是大型溶洞储集体物性参数测井定量评价研究，提供可靠的单井孔隙度、渗透率数据作为建模硬数据；二、缝洞型储层物性参数建模思路及方法。依据“缝洞离散分布相控”的建模思路，在储集体离散分布模型的相控约束下，建立储层物性参数模型；三、缝洞型储层物性参数建模模拟算法研究。开发基于协同型数学方法的建模算法，整合优选地震属性数据作为建模协变量，约束物性参数井间模拟。.本课题取得的主要研究进展和重要结果包括：一、建立了基于充填特征的缝洞储集体物性参数测井定量评价方法。比如综合考虑充填特征，分别采用微电阻率成像测井面孔率法、孔隙度赋值法和最优化测井解释程序计算孔隙度。二、提出“缝洞离散分布相控”的碳酸盐岩缝洞型油藏物性参数建模方法。在“储集体分类建模”思路的指导下，建立大型溶洞、溶蚀孔洞和裂缝储集体离散分布模型，在相控几何形态模型和物性空间分布模式建模协变量的双重约束下，分类建立不同类型储集体物性参数模型。三、开发适用于储层物性参数建模的随机模拟算法。使用带趋势的指示克里金算法等协同型数学算法，在模拟过程中引入地震属性、储集体发育概率体等协同约束数据，实现了对物性参数井间模拟的合理控制，提高所建储层物性参数模型的精度。最终形成了一套理论上可信、应用中可行的缝洞型油藏储层物性参数建模思路和方法。