摘要
库车坳陷大北—克拉苏构造带天然气经历过深埋高温作用,为了判定盐下天然气的母质类型和成因类型,根据镜质体反射率的计算公式和金刚烷与成熟度的关系计算成熟度;依据Behar关系图谱和碳同位素值图谱识别裂解气类型。通过地球化学数据最终计算出Ro达到1.5以上,达到裂解气的形成条件;裂解气类型为干酪根裂解气。并且进一步证实干酪根类型为自由型干酪根,与黏土矿物的催化关系不密切;从干酪根的聚集类型可证实为聚集型干酪根而非可溶有机质。综合分析得出大北—克拉苏构造带盐下天然气为腐殖型+依附型+聚集型干酪根裂解气。
The natural gas in Dabei - Kelasu tectonic belt of Kuche Depression has gone through deep buried and high temperature. In order to distinguish the genetic and parent material type of natural gas under evaporite bed,the maturity was calculated by the calculation formula of vitrinite reflectance and the relationship between adamantane and maturity. The cracked gas type was identified according to Behar relationship maps and carbon isotope values. Finally,by analyzing the geochemical data,the calculated Ro was above 1. 5,which reaches the formation conditions of the cracked gas. So the cracked gas type belonged to free type kerogen related to clay mineral catalysis. The aggregate type of kerogen was organic carbon instead of soluble organic matter. Comprehensive analysis showed that the nature gas under the evaporate bed of Da-bei - Kelasu tectonic belt is humus,free,and gathered kerogen pyrolysis gas.
出处
《复杂油气藏》
2014年第3期20-23,共4页
Complex Hydrocarbon Reservoirs
关键词
裂解气
成因识别
大北
-
克拉苏构造带
库车坳陷
cracked gas genetic identification Dabei - Kelasu tectonic belt Kuche Depression
