Maturation modeling in Otway basin, Australia
- CSIRO Division of Fossil Fuels, North Ryde, NSW, Australia
The Otway basin is a Jurassic to Pliocene sedimentary basin formed on the southern Australian continental margin. Its formation is associated with rifting and breakup of the Australian and Antarctic plates. Lithospheric cooling and contraction have probably produced post-breakup subsidence. Either lithospheric stretching or deep crustal metamorphism may have produced pre-breakup subsidence. These mechanisms have identifiable thermal histories. Organic diagenesis (specifically the reflectance of vitrinite in oil) is empirically determined by the thermal and depositional history of an organic sediment. Thus, the stages of hydrocarbon maturity of Otway basin sediments can be modeled. Depositional history is determined from ''geo-history analysis'' and thermal history depends on the subsidence mechanism applied to the basin. A paleo-heat-flow history derived from the deep crustal metamorphism model of subsidence produces a maturation profile with depth that is consistent with observed vitrinite reflectance data, although organic diagenesis modeling is relatively insensitive to precise details of thermal history. Depositional and maturation history modeling for the present day, 20 Ma ago, 40 Ma ago, and 60 Ma ago is applied to a seismic profile across the southern Australian continental shelf in the Otway basin as a demonstration of the projection backward in time of sedimentation and organic diagenesis.
- OSTI ID:
- 5700404
- Journal Information:
- Am. Assoc. Pet. Geol., Bull.; (United States), Journal Name: Am. Assoc. Pet. Geol., Bull.; (United States) Vol. 67:2; ISSN AAPGB
- Country of Publication:
- United States
- Language:
- English
Similar Records
Thermal subsidence of Santos and Sergipe-Alagoas Basins, Brazil - application to hydrocarbon exploration
Modeling thermal evolution and petroleum potential of basins formed by extension
Related Subjects
020200* -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
AUSTRALASIA
AUSTRALIA
CENOZOIC ERA
DIAGENESIS
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC HISTORY
GEOLOGIC MODELS
GEOLOGIC STRUCTURES
GEOLOGY
GEOPHYSICAL SURVEYS
JURASSIC PERIOD
MACERALS
MATURATION
MESOZOIC ERA
MINERAL RESOURCES
NATURAL GAS DEPOSITS
PETROLEUM DEPOSITS
PETROLEUM GEOLOGY
RESOURCES
SEDIMENTARY BASINS
SEDIMENTATION
SEISMIC SURVEYS
SURVEYS
TERTIARY PERIOD