High-Resolution Mass Spectrum Characteristics and Formation Mechanism of Low Maturity Oil in the Liaohe Western Depression
The Liaohe Western Depression is enriched in low-maturity oil resources,however the formation mechanism of its hydrocarbon remains unclear.GC/MS combined with ESI FT-ICR MS approaches are used to study the characteristics and formation mechanisms of low-maturity oil in the Gaosheng and Niuxintuo areas.The Gaosheng crude oil originated in a strongly reduced saline water environment,with its organic matter sourced from bacteria,algae,and terrestrial sources.The Niuxintuo crude oil originated in a reducing brackish water environment,with its organic matter primarily derived from a combination of microorganisms and terrestrial sources.Notably,the Niuxintuo crude oil exhibits a high wax content.The maturity parameters of the saturated hydrocarbons suggest that both sites contain low-maturity oils.Both low-maturity oils exhibited the presence of N1,N1O1,N1O2,O1,O2,O3,and O4 compounds.The Gaosheng low-maturity oil predominantly consists of N1 class compounds,while the Niuxintuo low-maturity oil is primarily composed of O2 class compounds.The former contains an abundance of fatty acids and hopanoic acid,whereas the latter is characterized by high levels of fatty acids and notably lower hopanoic acid content.This divergence underscores the differences in the forma-tion mechanisms of the two crude oils.The significant presence of hopanoic acid in the Gaosheng low-maturity oil suggests that the hydrocarbon source material underwent reformation by bacterium during the early diagenetic stage.The Gaosheng low-maturity oil results from a combined genetic mechanism involving early hydrocarbon generation from the biological lipids and bacterial reformation of the hydrocarbon source materials.The Niuxin-tuo low-maturity oil is abundant in fatty acids and higher plant waxes.Its formation mechanism involves early hydrocarbon generation from a significant quantity of biological lipids.Research into the genetic mechanisms of these two types of low-maturity oils provides a methodological approach for studying low-maturity oil genesis.This endeavor enhances our understanding of the genesis of low-maturity oils and provides guidance for exploring low-maturity oil in analogous basins.
Liaohe Basinlow-mature oilformation mechanismheteroatomic compoundhigh-resolution mass spectrometry
万方数据
维普
