哥伦比亚Magdalena盆地V油田沉积及演化特征

通过岩心、录井、测井等资料分析认为研究区为辫状河三角洲沉积，沉积主体为辫状河三角洲前缘亚相，只在研究区北端为辫状河三角洲平原沉积。研究区Guaduas组经历了两期湖平面的升降旋回，十几个短期旋回。由于辫状河道频繁改道，河漫滩以及水下分流河道间湾沉积形成的隔夹层分布广泛，储层的连通性变差，形成非常复杂的油水系统。储集砂体主要是水下分流河道与河口坝，物性受沉积微相的控制，河口坝砂体储层物性最好，水下分流河道次之，辫状河道最差。

Deposition and evolution of V oilfield in Magdalena Basin, Columbia

After analyzing the coring, cuttings and well logging data, it can be concluded that V oilfield belongs to braided river delta facies with braided river delta front as its main subfacies and braided river delta plain deposited only in the north. After two periods of up and down cycles, the lake level became the highest during Guad IV and Guad Ⅱ. The frequent river diversions, widespread interlayers formed by flood plain and underwater distributary interchannel deposition and poor reservoir connectivity have resulted in a very complex oil-water system. And the underwater distributary channel and mouth bar are the main reservoirs..As controlled by sedimentary microfacies, the reservoir property of mouth bar is the best, followed by underwater distributary channel, and braided river is the worst.