美国南佛罗里达盆地Sunniland原油和油源岩中芳烃的地球化学

本文用GC-MS技术分析了美国南佛罗里达盆地Sunnliand原油和油源岩抽提物中的芳烃,以便探讨碳酸盐岩环境中芳烃的分布特征,并用来重建古环境.Sunnliand原油和油源岩中含较半富的萘、菲、二苯并噻吩和三芳甾烷等化合物,甲基二苯并噻吩异构体呈V型分布.芴、氧芴和硫芴三系列化合物的相对含量以及其他地球化学特征如:Pr/Ph<1、正烷烃在C₂₂-C₃₀范围内呈偶碳优势、无或很少有二环倍半萜、含丰富的含硫芳烃等,指示Sunnliand原油和油源岩形成于海相强还原高盐环境.Sunnliand原油和油源岩中检出的一些化合物如:D环芳构化8,14-断藿烷、长链烷基苯、长链烷基苯并噻吩以及很高的延伸藿烷(C₃₁-C₃₅)和C₂₄、C₂₆四环萜烷表明Sunniland有机质有细菌输入.成熟度参数指示Sunniland原油和油源岩属未成熟至低成熟.

Geochemistry of Aromatic Hydrocarbons in Sunniland Oils and Source Rocks in the South Florida Basin,USA

Aromatic hydrocarbons in Sunniland oils and source rocks from South Florida Basin, USA , is analysed, in order to probe into the distribution characteristics of aromatic hydrocarbons and environmental paleoreconstruction. Sunniland oils and source rocks are richer in naphthalenes, phenanthrenes, dibenzothiophenes and triaromatic steroids; and methyldibenzothiophene isomers show V pattern. The relative abundances of fluorences, dibenzofurans and dibenzothiophenes and other geochemical characteristics such as Pr / Ph 1, the even preference of n-alkanes in the region C₂₂-C₃₀, low concentrations or absence of bicyclic sesquiterpanes and abundant aromatic-sulfur compounds indicate that Sunnliandd oils and source rocks were formed under the marine strongly reducing hypersaline environment. Some compounds such as D- ring aromatized 8, 14-secohopanes, long-chain alkylbenzenes and long-chain alkylbenzothiophenes and very abundant extented hopanes (C₃₁-C₃₅) and C₂₄, C₂₆ tetracyclic terpanes suggest that Sunniland organic matter can be related to the bacterial input. Maturity parameters (MPI1, MPI3, MDR4, 1, etc.) indicate that Sunniland oils and sourc rocks are immature to marginally mature.