Geoscience Australia - Product Database



Zeewyck Sub-basin

Entity ID: 22074 Compiled by: Bradshaw, B.E. Year: 2003 Status: Defined

Last Revised: 2013

Rank: subprovince Type: sedimentary Subtype: strike-slip fault-related Location: WA Off-shore

Synonyms: NA Symbol: NA

Minimum age: Recent Age method: inferred, seismic interpretation

Maximum age: Jurassic Age method: inferred, seismic interpretation

Summary: The ?Jurassic to Recent Zeewyck Sub-basin is a moderate size, deep water, frontier, strike-slip sub-basin within the Perth Basin containing at least 7 km of ?continental to marine strata.

Area (square kilometres): 15400
State: WA
Minimum present water depth (m): 1000
Maximum present water depth (m): 5000
Main rock types: siliciclastic sediments and sedimentary rocks
Jurassic-Lower Cretaceous
Main rock types: carbonate sediments and sedimentary rocks
Main depositional environment: marine
Maximum sediment thickness (m): 7000
Present crustal setting: continental
Country: AUS

Parent: Perth Basin

Child Provinces: No data

Adjoins - Houtman Sub-basin, Turtle Dove Ridge, Vlaming Sub-basin, Yallingup Shelf

Constituent units:

Events: No data

Mineral Deposits: No data

Key Reference: Bradshaw, B.E., Rollet, N., Totterdell, J.M., Borissova, I. 2003, A revised structural framework for frontier basins on the southern and southwestern Australian continental margin., Geoscience Australia. Record, 2003/03, 44 (Refid:13490)

Comments: No data

Overview: The Zeewyck Sub-basin a recently defined structural element of the Perth Basin that describes a north-south to northwest-southeast trending, strike-slip basin that extends over an area of 15,400 sq. km. It is a deep water (1 to 5 km water depth), frontier basin with no previous petroleum exploration. The main depocentre is located just west of the Houtman Sub-basin, and is characterised by a symmetrical, unfaulted sag wedge that overlies and onlaps an extensively faulted sedimentary section, and underlies a basinward-thinning passive margin cover. The faulted section is believed to contain at least 4 km of Jurassic continental to marine siliciclastics, while the sag fill contains up to 2 km of strata that are possibly equivalent to marine siliciclastics from the Lower Cretaceous Warnbro Group. Overlying passive margin strata are about 1.2 km thick, and are correlated with Aptian to Recent deepwater calcareous and argillaceous rocks from DSDP 259, drilled just west of the Zeewyck Sub-basin. Farther south, the Zeewyck Sub-basin is narrower and shows evidence for localised compressional tectonics with a small fold-thrust belt. The Zeewyck Sub-basin is believed to have been subjected to strike-slip tectonism along the Turtle Dove Transfer either during or just after breakup of the southwest Australian margin and Greater India during the Valanginian. The petroleum potential of the Zeewyck Sub-basin is difficult to evaluate due to the absence of well data to constrain the presence of source rocks. However, the Zeewyck Sub-basin may have generated hydrocarbons from Jurassic and Lower Cretaceous source rock intervals later (post Valanginian) than other source kitchens in the Perth Basin, and have provided a charge to structural and stratigraphic traps within the Zeewyck Sub-basin, and adjoining sub-basins. Some evidence for an active petroleum system in the Zeewyck Sub-basin is provided by SAR anomalies detected just south of the main depocentre.

Images: Perth Basin regional cross-section Profile 1 (53 KB), Perth Basin regional setting and cross-section location map (101 KB), Perth Basin regional cross-section Profile 8 (45 KB)

Other media: No data

Source Information:

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This report was generated on Monday, June 25, 2018 10:32:00 AM EST.