利用测井资料评价有利沉积相带及其储量分布

Study on the favorable facies evaluation and reservoir distribution by logging data

针对雁木西油田白垩系低阻油层受沉积相带及其断裂、构造和岩性等多种因素控制影响,测井信息应用难度增大的特点,提出利用多种测井响应提取单渗砂层能量厚度信息,使其曲线形态、特征和数据大小能够集中反映相对高渗的单渗砂层最大沉积能量及厚度变化,控制划分扇三角洲前缘水下辫状河道、浅水河道骨架砂体有利微相带的发育、规模及分布范围,克服了层段中几个成因相近薄砂层或砂泥互层中砂层累加厚度划分主体骨架砂体微相带的失误.通过该区白垩系井径、自然伽马、密度、中子、声波测井曲线和岩性、孔隙度及其能量厚度统计,建立起单渗砂层能量厚度下限标准,在该区白垩系目的层段储层中提取单渗砂层沉积能量,分析了水下辫状河道、浅水河道有利沉积微相带展布及其与油气聚集分布的关系.进而,分别采用浅水河道微相控制K1S1期、水下辫状河道控制K1S2、K1S3期储量计算,阐明了有利沉积微相带控制计算的储量参数及其分布,有效地圈定了各储量计算单元的含油面积和探明石油地质储量,为该区油藏增储上产和调整挖潜提供了可靠依据.

In the Yanmuxi oil region, the low resistivity reservoir is influent by sedimentary facies, fracture , structure and lithologic, so the logging information is difficult to use. In this paper we have picked up single sand thickness energy information by several logging methods to make it able to reflect the relatively high permeability＇s largest sedimentary energy and thickness divergence. On this basis, we find out that the underwater braided channel to shallow channel sand body are the favorable sedimentary microfacies and its distribution, so it overcome the lapse that the total sand thickness of several genetic similar thin sand layer or sand-clay layer to classify frame sedimentary facies. Through the statistic of diameter, natural gamma ray, density, neutrons, acoustic as well as lithologic character, porosity and sedimentary thickness statistic. We set up the lower limit of the energy thickness of SinglePermeability Sand Bed and picked up information of Single Permeability Sand Bed and other sedimentary energy . We analyzed the distribution of underwater braided channel microfacies and the favorable shallow water channel facies and we researched its relationship to reservoir distribution. Furthermore, the shallow water channel is controlling the KS1 period, the underwater braided channel is controlling the KIS2 and K2S3 period. Plus the effective thickness limit standards obtained by the reservoir log interpretation, favorable facies controlling the reserve calculation parameter and its distribution is explanted. So easch unit reserves area and geologic reserves are found out, and our effort gives reliable basis to the reserve increasing and potential capacityl seeking.