Integrated petroleum prospectivity assessment for a deep-water frontier basin based on structural restoration of the margin and 2D burial history modelling; Mentelle Basin, southwestern Australia

Author(s): Borissova, Irina; Nicholson, Chris; Krassay, Andrew; Neumann, Volkmar; Di Primio, Rolando; Boreham, Chris
Author Affiliation(s): Primary:
Geoscience Australia, Australia
Other:
FrOG Tech, Australia
GeoS4, Federal Republic of Germany
GeoForschungsZentrum Potsdam, Federal Republic of Germany
Volume Title: 33rd international geological congress; abstracts
Source: International Geological Congress [International Geological Congress, Abstracts = Congrès Géologique International, Résumés, Vol.33; 33rd international geological congress, Oslo, Norway, Aug. 6-14, 2008. Publisher:], [location varies], International CODEN: IGABBY
Note: In English
Summary: The Mentelle Basin is a large (36,400 km2) frontier basin lying less than 100 km to the west of the oil and gas producing Perth Basin. The basin was formed during Jurassic extension that preceded the breakup between Australia and Greater India in the Valanginian. The breakup was accompanied by significant volcanism with extensive basaltic lava flows overlying the Valanginian unconformity. The shallow-water eastern depocentre of the Mentelle Basin is a large complex half graben with up to 8 km of dominantly syn-rift sediments. The deep-water western depocentre contains up to 7 km of syn-rift and 2.5 km of post-rift section. Because no wells have been drilled in the basin, seismo-stratigraphic correlations are made to the DSDP well 258 on the Naturaliste Plateau and to the exploration wells in the southern Vlaming Sub-basin. However, direct correlations are possible only for the Late Cretaceous to Recent part of the section. Recent structural restoration of the margin, has shown similar major tectonic and accommodation cycles for both basins. The ages of the syn-rift sequences in the Mentelle basin therefore have been interpreted using the Vlaming Sub-basin tectonostratigraphic framework as an analogue. Seismic facies analysis defined potential source rock intervals and allowed correlation to the known source rocks in the Vlaming Sub-basin. To test the petroleum potential of this frontier basin, 2D burial history analysis has been performed for three regional lines. For each line, three different scenarios with varying source rock characteristics that reflect end member possibilities have been explored. The modelling results suggest that Jurassic source rocks in the deepest part of the syn-rift section are overmature, while uppermost Berriasian source rocks are immature. Source rocks that are currently within the maturation window are Middle Jurassic to Early Cretaceous shaly and coaly intervals, which commenced generation in the Late Jurassic. Erosion of significant sedimentary thickness in the eastern Mentelle Basin during continental breakup slowed down and, in some cases, stopped hydrocarbon generation. As this part of the basin has less that 1 km of post-rift section only source rocks with sufficient overburden are still generating. In the western Mentelle Basin, the same source rocks are buried much deeper and according to the model continued to generate throughout the Tertiary to the present. The main risk in the Mentelle Basin is whether good quality seals are present at the appropriate stratigraphic level. Existing seismic coverage is insufficient for a detailed structural interpretation at the play level to define potential traps. Provided suitable traps can be delineated, the Mentelle Basin may emerge as a prospective frontier basin. GA will collect about 2200 km of 2D seismic in the Mentelle Basin to infill the existing grid and constrain the current interpretation.
Year of Publication: 2008
Research Program: DSDP Deep Sea Drilling Project
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; 29 Economic Geology, Energy Sources; Basins; Blaming Subbasin; Burial; DSDP Site 258; Deep Sea Drilling Project; Half grabens; Indian Ocean; Jurassic; Leg 26; Mentelle Basin; Mesozoic; Naturaliste Plateau; Oil and gas fields; Overburden; Paleoenvironment; Perth Basin; Petroleum; Sedimentary basins; Shallow-water environment; Two-dimensional models
Coordinates: S334742 S334741 E1122826 E1122825
Record ID: 2010056346
Copyright Information: GeoRef, Copyright 2018 American Geosciences Institute. Reference includes data supplied by International Geological Congress Organizational Committee