轻烃录井在凝析气藏气源判识中的应用  

Application of light hydrocarbon logging in gas source identification of condensate gas reservoir

作　　者：李哲[1] LI Zhe(Research Institute of Exploration and Development,Jilin Oilfield Company,PetroChina,Songyuan, Jilin 138000,China)

机构地区：[1]中国石油吉林油田公司勘探开发研究院,吉林省松原市138000

出　　处：《录井工程》2020年第2期37-40,共4页Mud Logging Engineering

基　　金：中国石油吉林油田公司科技项目“梨树-双辽天然气目标评价及有效开发技术研究”(编号:201818)。

摘　　要：梨树断陷苏家次洼火石岭组油气分布比较复杂,实际录取获得的各类实验室分析化验资料已不能满足当前研究的需要。为进行该区凝析气藏天然气成因和气源的判识,基于轻烃录井资料,使用C7轻烃化合物(MCC6、nC7、∑DMCC5)三角图板和C5-C7轻烃化合物(正构烷烃、异构烷烃、环烷烃)三角图板来识别天然气的成因类型,结合“(2-甲基己烷+3-甲基己烷)/正己烷”和“甲基环己烷/正庚烷”这2项指标对该地区天然气气源进行判识,并探讨了该区凝析气藏的形成机制。结果表明苏家次洼中环带凝析气藏天然气主要来源于腐泥型母质(有机质类型为Ⅱ1型和Ⅰ型干酪根);天然气主要由深凹陷带沙河子组早期原油裂解运移而来;火石岭组受两期油气充注过程的影响,晚期的气侵导致早期形成的油藏相态发生变化,使得该区中环带形成凝析气藏。Poor understanding of the hydrocarbon distribution pattern is the major constraint of petroleum exploration in Huoshiling Formation in Sujia Sub-depression of Lishu Fault Depression at present.All kinds of laboratory analysis data obtained by practical can not meet the needs of oil and gas exploration.To identify the genesis and gas source of the natural gas in the condensate gas reservoirs,based on the light hydrocarbon logging data,the genetic types of natural gas were identified by using triangular charts of the C7 light hydrocarbon compounds(MCC6,nC7,∑DMCC5)and the C5-C7 light hydrocarbon compounds(normal paraffin hydrocarbons,isoalkane,cycloparaffinic hydrocarbon),the gas sources of the natural gas in this area were determined by combining the two indicators of(2-methylhexane+3-methylhexane)/n-hexane and methylcyclohexane/n-heptane,and the formation mechanism of condensate gas reservoir in this area was studied.The results show that the main source of natural gas of the condensate gas reservoir in the middle ring zone of Sujia Sub-depression is sapropelic parent material(the organic matter types are typeⅡ1 and typeⅠkerogens);natural gas is mainly from the early crude oil cracking and migration of Shahezi Formation in deep depression;affected by the two stages of hydrocarbon charging process in Huoshiling Formation,the late gas invasion leads to the change of the phase behavior of the oil reservoir formed in the early stage,which makes the middle ring zone of this area form condensate gas reservoir.

关 键 词：凝析气藏 轻烃录井 天然气成因 气源 成藏机制 

分 类 号：TE132.1[石油与天然气工程—油气勘探]