塔里木盆地和田河气田轻质油成熟度判定及其油源意义  

Maturity of light oil and its significance in indicating oil source in Hetianhe gas field,Tarim Basin

作　　者：崔景伟[1,2] 王铁冠[2] 胡健[2] 李美俊[2] 

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油大学油气资源与探测国家重点实验室,北京102249

出　　处：《石油与天然气地质》2013年第1期27-36,共10页Oil & Gas Geology

基　　金：国家自然科学基金项目(40972089)

摘　　要：为评价和田河气田轻质原油的成熟度,利用气相色谱与气相色谱-质谱联用仪,对和田河气田4个轻质原油中具有成熟度信息的化合物进行分析。轻烃庚烷值与异庚烷值、甲基双金刚烷参数、甲基菲参数、甲基二苯并噻吩参数和Ts/(Ts+Tm)成熟度参数显示和田河轻质油处于高成熟阶段(凝析油阶段),烷基萘类成熟度参数、C29甾烷20S/(20S+20R)和C29甾烷ββ/(αα+ββ)显示尚未进入生烃高峰期。轻烃等参数显示原油高成熟与原油密度等物理性质一致,烷基萘类成熟度参数成熟度偏低可能与原油存在轻微生物降解有关,甾烷成熟度参数偏低是演化达到平衡终点后翻转所致。综合成熟度参数认为,和田河气田轻质原油处于成熟末期-高成熟阶段。与该地区典型的烃源岩样品成熟度对比,推断轻质原油与天然气同源,主要来自寒武系烃源岩。甾萜类生物标志物油-源对比分析支持该结论。GC and GC-MS analysis was performed on compounds possibly containing information on maturity in four light oil samples selected in Hetianhe gas field. Maturity indexes including heptane index, isoheptane index, methyldiamantane index, MPI, methyldibenzothiophene （MDBTs）and Ts/（ Ts ＋ Tm）indicate that the light oil in Hetianhe gas field is at high maturation stage（ gas condensate）. In contrast, methylnaphthalene, C29 sterane 20S/ （20S ＋ 20R）and C29 sterane ββ（ αα＋ββ）suggest that the source rocks have not entered peak oil generation stage. Indexes such as light hydrocarbon show that high maturity of the light oil is consistent with its physical properties. The anomalies of naphthalenes may be the result of weak biodegradation, while the low sterane indexes may be the result of overturning at the end of evolutionary balance. Comprehensive analyses of the matu- rity indexes reveal that the light oil is at the end of maturation-high maturation stage. Furthermore, comparison with the typical local source rocks indicates that both the light source rocks, a conclusion supported by oil-source correlation oil and natural gas are generated by the Cambrian based on sterane and teroane.

关 键 词：成熟度参数 油源 轻质油 和田河气田 塔里木盆地 

分 类 号：TE132[石油与天然气工程—油气勘探]