Organic geochemical characteristics of crude oils from the Masila Basin, eastern Yemen

The Masila Basin is an important hydrocarbon province in Yemen, but the origin of hydrocarbons and their generation history are not fully understood. In this regard, 10 crude oils from different petroleum reservoir sections in the Masila Basin were characterized by a variety of biomarker and non-bio...

Full description

Saved in:
Bibliographic Details
Published in:Organic geochemistry 2011-06, Vol.42 (5), p.465-476
Main Authors: Hakimi, Mohammed Hail, Abdullah, Wan Hasiah, Shalaby, Mohamed Ragab
Format: Article
Language:English
Subjects:
biomarkers
carbon
clay
Earth sciences
Earth, ocean, space
Exact sciences and technology
gas chromatography
Hydrocarbons
Isotope geochemistry
Isotope geochemistry. Geochronology
marine environment
mass spectrometry
oils
organic matter
petroleum
rocks
Sedimentary rocks
stable isotopes
Stratigraphy
sulfur
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The Masila Basin is an important hydrocarbon province in Yemen, but the origin of hydrocarbons and their generation history are not fully understood. In this regard, 10 crude oils from different petroleum reservoir sections in the Masila Basin were characterized by a variety of biomarker and non-biomarker parameters using GC, GC–MS and stable carbon isotope techniques. Oils from the Masila Basin display pristane/phytane (Pr/Ph) ratios ranging from 1.7 to 2.0, low sulfur content, high C 35 homohopane index, relatively high C 27 sterane concentrations and relatively high tricyclic terpanes suggesting a marine clay source rock that was deposited in mildly anoxic to suboxic conditions with dominantly algal organic matter. C 29 20S/(20S + 20R) steranes and ββ/(ββ + αα) sterane ratios indicate that the Masila oils have reached peak oil window maturity. Another related feature of these oils is the absence of 18α (H)-oleanane, which suggests a source age older than Cretaceous. The carbon isotope compositions are similar to those of the potential source rocks, which range from −25.4‰ to −28.3‰, indicating a marine environment. The new data presented in this paper suggest that the Masila oils constitute one oil family and that the oil originated from the Upper Jurassic Madbi source rock in the basin.
ISSN:0146-6380
1873-5290
DOI:10.1016/j.orggeochem.2011.03.015