吐哈盆地稠油特征及稠变机制

CHAEACTERISTICS OF HEAVY OIL AND THICKENING MECHANISM IN TUHA OIL FIELD

由于烃源岩低熟成烃及成藏后期稠化,造成吐哈盆地稠油密度、粘度普遍偏高,而降解程度相对较低,多属于中、低降解程度。古构造背景、断层发育及油藏内部连通性直接控制着不同区块原油的降解程度,呈现东强西弱、上油组降解程度强而下油组降解较弱的特点。成藏后期生物降解、水洗及扩散等因素的共同作用是导致本区原油稠变主要原因。

Owing to generating hymn of premature hydrocarbon source rock and thickening of reservoir formed in later stage the high density, High viscosity and low degree of degradation were formed and the most is in low and medial degrees of degradation. The degree of degradation of oil in different blocks of the basin is directly controlled by paleostructure, Fault development and interior connectivity of reservoir and present the characteristic which is high in the east and low. in the west, And high in upper oil formation group and low in lower oil formation group. The main reason of oil thickened in the area is the interaction of such factors as biodegradation, Water washing and diffusion in later stage of forming reservoir.