ePrints

Early generation of 20S-5α(H),14α(H),17α(H)- and 5α(H),14β(H),17β(H)-steranes in low salinity lacustrine shales

Lookup NU author(s): Professor Stephen Larter

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.

Abstract

A quantitative sterane biomarker study was conducted on a series of paralic freshwater lacustrine shale samples ranging in maturity from immature to near oil window maturity taken from Section 3 of the Shahejie Formation (Es3) in the Liaohe Basin, N.E. China. Concentrations of 5 alpha(H),14 alpha(H),17 alpha(H)-20S and 5 alpha(H),14 beta(H),17 beta(H)-steranes remain nearly constant throughout the sample suite. However, the decrease in the absolute concentrations of the 20R-5 alpha(H),14 alpha(H),17 alpha(H)-C-29 steranes with increasing maturity results in an increase in the conventionally defined maturity parameters, 20S/(20S + 20R)-alpha alpha alpha and alpha beta beta/(alpha alpha alpha + alpha beta beta) sterane ratios. In addition, the data suggest that relatively early generation of 5 alpha(H),14 alpha(H),17 alpha(H)-20S and 5 alpha(H),14 beta(K),17 beta(H)-steranes has occurred in lacustrine sediments with a vitrinite reflectance similar to 0.3% (R(o)). The data provide strong support for the major importance of relative thermal stability of epimers, but do not exclude the possibility of isomerization as a viable mechanism for production.

Publication metadata

Author(s): Li MW, Larter SR, Mei B

Publication type: Article

Publication status: Published

Journal: Organic Geochemistry

Year: 1994

Volume: 22

Issue: 6

Pages: 893-902

Print publication date: 01/12/1994

ISSN (print): 0146-6380

ISSN (electronic): 1873-5290

Publisher: Pergamon

URL: http://dx.doi.org/10.1016/0146-6380(94)90027-2

DOI: 10.1016/0146-6380(94)90027-2

Altmetrics

Share