The present study focused on the Permian to Jurassic sequence in the Northern Highlands
area, NW Jordan. The Permian to Jurassic sequence in this area is thick and deeply buried, consisting
mainly of carbonate intercalated with clastic shale. This study integrated various datasets, including
total organic carbon (TOC, wt%), Rock-Eval pyrolysis, visual kerogen examination, gross composition,
lipid biomarkers, vitrinite reflectance (VRo%), and bottom-hole temperature measurements. The
main aim was to investigate the source rock characteristics of these strata regarding organic richness,
kerogen type, depositional setting, thermal maturity, and hydrocarbon generation timing. The
Permian strata are poor to fair source rocks, primarily containing kerogen type (KT) III. They are
immature in the AJ-1 well and over-mature in the NH-2 well. The Upper Triassic strata are poor
source rocks in the NH-1 well and fair to marginally good source rocks in the NH-2 well, containing
highly mature terrestrial KT III. These strata are immature to early mature in the AJ-1 well and at
the peak oil window stage in the NH-2 well. The Jurassic strata are poor source rocks, dominated
by KT III and KT II-III. They are immature to early mature in the AJ-1 well and have reached the oil
window in the NH-2 well. Biomarker-related ratios indicate that the Upper Triassic oils and Jurassic
samples are source rocks that received mainly terrestrial organic input accumulated in shallow
marine environments under highly reducing conditions. These strata are composed mostly of clayrich
lithologies with evidence of deposition in hypersaline and/or stratified water columns. 1D basin
models revealed that the Upper Triassic strata reached the peak oil window from the Early Cretaceous
(~80 Ma) to the present day in the NH-1 well and from ~130 Ma (Early Cretaceous) to ~90 Ma (Late
Cretaceous) in the NH-2 well, with the late stage of hydrocarbon generation continuing from ~90 Ma
to the present time. The present-day transformation ratio equals 77% in the Upper Triassic source
rocks, suggesting that these rocks have expelled substantial volumes of hydrocarbons in the NH-2
well. To achieve future successful hydrocarbon discoveries in NW Jordan, accurate seismic studies
and further geochemical analyses are recommended to precisely define the migration pathways.
Research Abstract
Research Date
Research Department
Research Journal
Minerals
Research Member
Research Year
2024