基于岩性定量判别的潜山演化模式与储层发育机理

BURIED HILL EVOLUTION MODEL AND RESERVOIR FORMING MECHANISM BASED ON QUANTIRATIVE LITHOLOGICAL STUDIES

PL油田为国内第1个大型花岗岩潜山油田,发育孔隙裂缝型储层,潜山岩性多样,平面分布规律及其对储层的控制作用复杂,研究难度大。利用PL油田的岩矿和测井资料识别了岩浆岩和变质岩双重潜山结构;利用岩心岩屑的元素数据和QAPF岩性分类法,判别二长花岗岩和花岗闪长岩2种岩性,结合常规测井资料,首次建立了基于自然伽马的可细分酸性岩浆岩的判别标准;在此基础上,明确了岩性变化规律,探讨了潜山演化及岩性变化模式,并对岩性的平面变化对潜山储层发育的影响进行了机理分析。该研究为后期开发寻找优质储层奠定了基础,以期对同类型潜山油藏储层研究具有指导意义。

The PL oilfield is the first large terized by lithological diversity and porou voir, therefore, remains critical, even it is granitic buried hill oilfield s fractured reservoirs. Stu discovered in China. It is ch dy of the lithology of the r arac- eser- quite difficult. Upon the mineralogy and well logging data, a double structure of buried hill consisting of Proterozoic metamorphic rocks and Mesozoic igneous rocks respectively has been recognized. As for the igneous rocks, according to the element composi- tion of the rocks and following the QAPF lithology classification, granodiorite and monzogranite are i- dentified. In combination with well logging data, quantitative discriminant criteria for buried hill igne- ous rocks are established for the first time. On this basis, the lithology variation is carefully studied, which found the basis for the construction of the buried hill evolution model. In addition, the variation in buried hill lithology and the influence of lithology on the development of buried hill reservoirs are thoroughly discussed. The study results is believed useful in the further research and development of buried hill reservoirs.