CAJ | 학술논문

晚三叠世延长期鄂尔多斯为陆相坳陷盆地,主要发育湖泊三角洲相沉积,油藏主要为低-特低渗透岩性油藏.研究表明,长7生烃作用形成的异常高压是石油向低渗透储层运移的主要动力,运移方式主要为幕式运移.通过成藏物理模拟手段分析不同压力条件下低渗透成藏过程及成藏特征,同时对比不同注入压力、不同充注方向下幕式成藏特征及与稳态成藏的差异.实验结果表明,无论烃源岩向上还是向下排烃,异常压力越大越有利于低渗透储层成藏,成藏效率越高,含油饱和度越高.
만삼첩세연장기악이다사위륙상요함분지,주요발육호박삼각주상침적,유장주요위저-특저삼투암성유장.연구표명,장7생경작용형성적이상고압시석유향저삼투저층운이적주요동력,운이방식주요위막식운이.통과성장물리모의수단분석불동압력조건하저삼투성장과정급성장특정,동시대비불동주입압력、불동충주방향하막식성장특정급여은태성장적차이.실험결과표명,무론경원암향상환시향하배경,이상압력월대월유리우저삼투저층성장,성장효솔월고,함유포화도월고.
In the late Triassic Yanchang period,the Ordos Basin was a continental depression basin.The deposits of lake-delta facies are prevalent, and hydrocarbon reservoirs are mainly low-and ultra-low-permeability litholo-gic type.A research into the area reveals that the abnormally high pressure resulted from hydrocarbon generation in the Chang-7 Formation serves as the major dynamic force for the episodic migration of oil toward low-permeability reservoirs.Physical simulation was performed to analyze the process and features of hydrocarbon accumulation in low-permeability reservoirs under different pressures and to compare the characteristics of episodic hydrocarbon accumulation and steady hydrocarbon accumulation under different charging pressures and at different charging direction.The results show that,regardless the direction of hydrocarbon expulsion from source rocks,the higher the pressure in the low-permeability lithology reservoirs is,the higher the hydrocarbon accumulation efficiency and the oil saturation are.