摘要
柴达木盆地西部古近-新近系的地层压力剖面可分为3种类型,其主要特征为:Ⅰ型是地层压力随深度增加呈常压段和异常超压段两段型;Ⅱ型类似于Ⅰ型,但在异常超压段有压力突降点;Ⅲ型是地层压力随深度变化的趋势呈单段式,压力值常在静水压力线附近变化。Ⅰ型地层压力剖面主要分布在沉降为主区;Ⅱ型主要分布在沉降为主区的断裂发育区;Ⅲ型主要分布在剥蚀区内。柴达木盆地西部古近-新近系油气田分布主要与地层压力类型(Ⅱ型和Ⅲ型)有关,其原因主要是在油气水共存的条件下,压力的降低可导致油气大规模运移。
The formation pressure profile of western Qaidam basin is divided into 3 types and characterized by those as follows： Type Ⅰ ap- pears the increase of formation pressure with depth by normal pressure section and abnormal uverpressure section; Type Ⅱ is similar to Type Ⅰ except for pressure drop point in the abnormal overpressure section; Type Ⅲ： the trend of the formation pressure changing with depth occurs in single seetion, namely, the pressure changes normally nearby the hydrostatic pressure line. The formation pressure profile of Type Ⅰ mainly appears in settling area, that of Type Ⅱ in fault or fracture developing area of it, while that of Type Ⅲ in denudation area. The distribution of oil and gas fields of the Tertiary in western Qaidam basin is mainly related to Type Ⅱ and Type Ⅲ profiles with pressure drops. And the main reason is probably that the pressure drops could lead to the large scale migration of oil and gas in condition of coexist- ing oil, gas and water.
出处
《新疆石油地质》
CAS
CSCD
北大核心
2012年第6期651-653,共3页
Xinjiang Petroleum Geology
关键词
柴达木盆地
压力剖面
成因
油气田
Qaidam basin
furmation pressure profile
origin
oil-gas field
