The southern Bonaparte Gulf, northwest Australia - A basin model
- Western Mining Corp., Perth (Australia)
- Cultus Petroleum, Perth (Australia)
The Bonaparte Gulf basin Palaeozoic rift is an extension of the Petrel subbasin-Sahul syncline trend forming one arm of a rift triple junction, Salt tectonics developed in this rift setting are fundamental to a new model of the basin and have influenced the development of three Palaeozoic megasequences defined in the model. Megasequence I (MS-I), Silurian-Devonian restricted, synrift sedimentation was associated with extensive evaporitic systems which developed rich source rocks and massive halites. Early basinward salt withdrawal influenced sediment distribution and structuring, localizing shallow-water carbonates above deep salt ridges. Megasequence II (MS-Il) Late Devonian-Late Carboniferous sedimentation is restricted to subbasins formed by continued basinward salt withdrawal. Turbidites were channelled and stacked along subbasin axes during active subsidence (Milligans Formation), and shallow-water carbonate banks continued to develop on basin highs. As subsidence eased, eustatically controlled deltaic sedimentation filled the subbasins, culminating in deposition of a regional shallow-water carbonate (Tanmurra Formation). Continued salt withdrawal in the north produced a carbonate shelf break evidenced by the apparent termination of the Tanmurra Formation seismic reflector, coincident with the carbonate complex development which exhibits continued growth until this period. An overlying unit (Point Spring Sandstone) marks the transition to the next megasequence. Megasequence III (MS-Ill) Late Carboniferous-Late Permian marginal marine/fluvial sedimentation is associated with renewed rifting in the northwest. Associated driving subsidence produced northwest tilting, which was reinforced by Mesozoic-Cenozoic passive margin subsidence following the Late Jurassic continental breakup and abandonment of the northwest-southeast Paleozoic rift arm.
- OSTI ID:
- 7091896
- Report Number(s):
- CONF-900605--
- Journal Information:
- AAPG Bulletin (American Association of Petroleum Geologists); (USA), Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (USA) Vol. 74:5; ISSN AABUD; ISSN 0149-1423
- Country of Publication:
- United States
- Language:
- English
Similar Records
Definition of basin phases in the Petrel Sub-basin (Australia): Implications for the development of Palaeozoic petroleum systems
The southern Bonaparte Gulf, northwest Australia - New exploration plays
Related Subjects
020200* -- Petroleum-- Reserves
Geology
& Exploration
58 GEOSCIENCES
580000 -- Geosciences
AUSTRALASIA
AUSTRALIA
CARBONATE ROCKS
CARBONIFEROUS PERIOD
DEVONIAN PERIOD
EVAPORITES
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC FORMATIONS
GEOLOGIC MODELS
GEOLOGIC STRUCTURES
JURASSIC PERIOD
MESOZOIC ERA
PALEOZOIC ERA
PERMIAN PERIOD
RIFT ZONES
ROCKS
SALT DEPOSITS
SANDSTONES
SEDIMENTARY BASINS
SEDIMENTARY ROCKS
SEDIMENTATION
SILURIAN PERIOD
TECTONICS