CAJ | 학술논문

东海陆架盆地西湖凹陷平湖构造带古近纪平湖组普遍发育异常压力，探讨地层高压发育的特征及其与油气分布的关系，旨在为油气勘探提供地质依据。以声波时差资料为基础，结合测井、地质、地化及油气测试资料，利用Bowers法计算单井地层压力，恢复平湖构造带单井压力剖面，以实测地层压力结果为约束，分析地层压力的分布特征。认为该构造带异常高压主要分布在埋藏较深的平湖组，随深度增加，高压幅度呈阶梯状增大；平湖构造带不同构造单元高压顶界面的深度具有明显差异，从平中区向平北区高压异常顶界面有变深的趋势，其中平中区为3．3 km，平北区为3．7 km。压力场的纵向叠置决定了油气的分布，高压发育与油气层分布的耦合关系分为4种类型：双封闭高压型、双封闭压力过渡型、单封闭压力过渡型、单封闭常压型，其中以双封闭压力过渡型和单封闭常压型为主。单封闭常压带、双封闭压力过渡带和双封闭高压带的顶部为油气的有利聚集区。
동해륙가분지서호요함평호구조대고근기평호조보편발육이상압력，탐토지층고압발육적특정급기여유기분포적관계，지재위유기감탐제공지질의거。이성파시차자료위기출，결합측정、지질、지화급유기측시자료，이용Bowers법계산단정지층압력，회복평호구조대단정압력부면，이실측지층압력결과위약속，분석지층압력적분포특정。인위해구조대이상고압주요분포재매장교심적평호조，수심도증가，고압폭도정계제상증대；평호구조대불동구조단원고압정계면적심도구유명현차이，종평중구향평북구고압이상정계면유변심적추세，기중평중구위3．3 km，평북구위3．7 km。압력장적종향첩치결정료유기적분포，고압발육여유기층분포적우합관계분위4충류형：쌍봉폐고압형、쌍봉폐압력과도형、단봉폐압력과도형、단봉폐상압형，기중이쌍봉폐압력과도형화단봉폐상압형위주。단봉폐상압대、쌍봉폐압력과도대화쌍봉폐고압대적정부위유기적유리취집구。
The abnormal pressure develops commonly in Paleogene Pinghu Formation of the Pinghu tectonic belt,East China Sea shelf basin.This paper discusses the characteristics of the abnormal high pressure developing in strata and their relationship with the distribution of oil and gas in order to provide geological bases for oil and gas exploration in the study area.Based on the acoustic travel time data and combined with the logging,geological,geochemical and formation test data,the paper uses the Bowers method to calculate the pore fluid pressure of the single well and restores the single well pressure profile of the Pinghu tectonic belt.The measured formation pressure is used to analyses the characteristics of the distribution of formation pressure.The result shows the abnormal high pressure in this tectonic belt is mainly distributed over the deeper buried Pinghu Formation,with the increase of depth, the overpressure increases as ladder-shape;The burial depths of the reservoirs with abnormal high pressure in different tectonic units of the Pinghu tectonic belt are obviously different. The burial depth of the reservoirs with abnormal high pressure in the Pingzhong area is 3. 3 km,and the that of the reservoirs with abnormal high pressure in the Pingbei area is 3. 7 km,indicating that the burial depths of the reservoirs with abnormal high pressure,from the Pingzhong area to the Pingbei area will become deeper and deeper.The vertical superimposed pressure field determines the distribution of oil and gas.The coupling relationship of the overpressure and the distribution of hydrocarbon zones can be divided into four types:the double seal type with high pressure,the double seal type with transitional pressure,the single seal type with transitional pressure,and the single seal type with normal pressure.The double seal type with transitional pressure and the single seal type with normal pressure are more common in the study area.The top of the zone of the single seal type with normal pressure,the top of the zone of the double seal type with transitional pressure and the top of the zone of the double seal type with high pressure are the favorable accumulation areas of oil and gas .