酒西盆地老君庙油田古近纪L油藏富油因素分析

酒西盆地为晚期型前陆盆地,老君庙油田位于盆地南部老君庙背斜带的中部,L油藏储层颗粒分选、磨圆较差,成分成熟度和结构成熟度较低,胶结物的成分主要为泥质和钙质,属中高孔隙中渗透含油好的油藏。依据岩心观察、野外露头以及钻井、测井等沉积相划分标志,老君庙油田L油藏主要发育河流、三角洲等2类沉积相,辫状河、三角洲平原、三角洲前缘等3类沉积亚相。老君庙油田古近纪L油藏上部沉积区域性的石油沟段棕红色泥岩盖层,L1,L2,L3储集砂体由于褶皱作用形成背斜圈闭,西部低洼地区为构造-岩性圈闭,其中控制油气运移和聚集的构造背景是成藏的地质基础,成岩作用形成的储集物性特点是成藏的前提,控制优质储层发育的沉积相带是成藏的必要条件,良好的生储盖组合配置是成藏的关键。

Enrichment of the paleogene L Reservoir in Laojunmiao Oilfield of Jiuxi Basin

Laojunmiao Oilfield is located in the center of Laojunmiao anticline of the Jiuxi Basin,which is a advanced foreland basin. The grainsize sorting and psephicity of the L reservoir is poor, and the mat uration of composition and structure is low, the main content of cement are shale and calcium, so the L reservoir is a good reservoir,with midhigh porosity and middle permeability. Based on the classification mark about sedimentary facies, including core observation, outcrop, drilling,logging and so on, the L res ervoir can be divided into 2 sedimentary facies and 3 sedimentary subfaeies, the facies are fluvialite and delta facies, the subfacies are braided fluvial and delta plain, delta front. The upper of the L reservoir de posited regional brownred mudstone caprocks of Shiyougou formation, the sandbody of L1 and L2, L3 formed anticline reservoir due to the folding, there is structurallithologic reservoir in the west, the tec tonic settings of controling migration and accumulation are the geological background of accumulation, the physical property features of diagenesis reservoir are the premises of accumulation, the sedimentary facies which control the quality development of the reservoir are the necessary conditions of accumula tion, the well assemblage for sourcereservoircap is the key to accumulation.