摘要
冀北坳陷中上元古界一下古生界是一套以碳酸盐岩为主的海相沉积岩系,其内广泛发育有结晶、重结晶作用形成的方解石、萤石、石英、重晶石等矿物。通过对这些矿物中流体包裹体特征的系统研究,划分出六类有机(烃)包裹体和三类水溶液包裹体。这些流体包裹体分别是由油气和油田水两种不混溶流体所形成;在这两种不混溶流体运移过程中,油田水以连续相形式存在,而油气以分散相(珠滴、气泡)形式悬浮于其中。按地层层序,各地层流体包裹体的均一温度表现出在上、下高,而中间低的特点。同一地层在坳陷不同部位,其均一温度也明显不同,但油气是由高温区向低温区运移。另外,据各地层中有机包裹体发育的类型和数量,推测此坳陷内油气主要储集层是中上元古界的铁岭组、雾迷山组,以及下古生界的奥陶系。
There is a set of marine-facies sedimentary series which are mainly composed of carbonate rock for middle-upper Proterozoic and lower Palaeozoic sub-erathem of Jibei depression.The sedimentary formation have many minerals which are formed by crystallization and recrystallization such as calcite,fluorite,quartz,barite ect.Through making a systematic study to fluid inclusions characteristics in these minerals,there are six types hydrocarbon inclusions and three kinds aqueous inclusions have been differentiated.These fluid inclusions separately formed by two immiscible fluid oil-gas and oil field water.During the two immiscible fluid migration,oil field water exist within it by continuous phase,and oil-gas by dispersed phase (drop,bubble). In these fluid inclusions,the vapor volume of vapor-liquid aqueous inclusions are between 1～10%,and it' s salinity between 1.73～9.86% (NaCl),and average is 4.72%(NaCl),showing that it came from paleo-seawater.The homogenization temperature of the aqueous inclusions is in the range 47-173℃,and the homogenized phase is liquid phase which represents the lowerest formation temperature for oil-gas migration and reservior in the depression.The hydrocarbon inclusions are the direct sign of oil-gas primary and secondary migration,in which the vapor volume of oil-gas hydrocarbon inclusions is in the range 2～10%,and its homogenization temperature is between 41 -186℃with the oil homogenized phase showing that oil-gas migration and reservoir was in oil phase.When forming temperature is lower,the homogenization temperature of hydrocarbon inclusion is lower than aqueous inclusion.But when the temperature is higher,the homogenization temperature of aqueous inclusion is lower than hydrocarbon inclusion. According to the strata sequence of middle-upper Proterozoic and lower Palaeozoic sub - erathem in Jibei depression,the mean homogenization temperature of fluid inclusion is higher in the top and bottom of strata,and lower in the middle strata.This is because that there are giant thick-b
出处
《沉积学报》
CAS
CSCD
北大核心
1997年第A12期35-40,共6页
Acta Sedimentologica Sinica
关键词
液包体
地质意义
坳陷
上元古界
油气田
aqueous inclusions
hydrocarbon inclusions
Middle-upper Proterozoic suberathem
Lower Palaeozoic subeathem
Jibei depression
