大庆长垣东西两侧青一段泥岩超压形成与演化的差异性

Difference of formation and evolution of overpressure of K1qn1 mudstone east and west of Daqing placanticline

在泥岩超压形成与演化规律研究的基础上,分析了泥岩超压演化模式,研究了松辽盆地北部青一段泥岩超压形成与演化规律.通过对比大庆长垣东西两侧青一段泥岩超压形成与演化差异得到,虽然大庆长垣西部青一段超压值目前略大于大庆长垣东部超压值,但大庆长垣东部青一段泥岩超压开始形成时期略早于大庆长垣西部形成时期,大庆长垣东部扶杨油层油气主要成藏时期—嫩江组沉积末期古超压值明显大于西部超压值,大庆长垣西部目前较高的超压值形成时期明显晚于东部形成时期,这3个差异造成了大庆长垣东部扶杨油层油气运移和保存条件明显好于西部油气运移和保存条件,大庆长垣东部油气藏分布明显多于西部的油气藏分布.

Based on the study of formation and evolution laws of overpressure in mudstone,formation and evolution of overpressure of K1qn1 mudstone in the north of Songliao Basin was studied by the analysis of evolution models of overpressure in mudstone.By the contrast of formation and evolution of overpressure of K1qn1 mudstone between in the east and in the west of Daqing placanticline,overpressure of K1qn1 mudstone in the west of Daqing placanticline now is slightly bigger than that in the east,but the formation period of overpressure of K1qn1 mudstone in the east of Daqing placanticline is slightly earlier than that in the west.Ancient overpressure of K1qn1 mudstone in the east of Daqing placanticline is obviously bigger than that in the west in the main oil-gas accumulation period in F,Y oil layers during the end of Lenjiang sedimentary period.The formation period of high overpressure in the west of Daqing placanticline now was considered to be obviously later than that in the east now.The three differences are attributed to the fact that oil-gas migration and preservation conditions of F,Y oil layers in the east of Daqing placanticline is obviously better than that in the west.The distribution of oil-gas reservoirs of F,Y oil layers in the east of Daqing placanticline is obviously larger than that in the west.