Late Artinskian–Early Kungurian (Early Permian) warming and maximum marine flooding in the East Gondwana interior rift, Timor and Western Australia, and comparisons across East Gondwana
MetadataShow full item record
© 2016Substantial new information is presented on upper Artinskian–Kungurian deposits in Timor-Leste and in the Canning, Southern Carnarvon and northern Perth basins of Western Australia. These basins, situated between about 35°S and 55°S palaeolatitude, formed part of the East Gondwana interior rift, a precursor to the rift that 100 my later formed the Indian Ocean in this region. Timor lay near the main axis of the East Gondwana interior rift, whereas the Western Australian basins were marginal splays from the rift axis. The main depocentres developed as a result of faulting that was initiated during the Late Pennsylvanian. Detailed lithostratigraphic and biostratigraphic analyses have been made on the newly recognized Bua-bai limestone and the type Cribas Group in Timor, the Noonkanbah Formation in the Canning Basin, the Byro Group in the Merlinleigh Sub-basin of the Southern Carnarvon Basin, and the Carynginia Formation in the northern Perth Basin. In Timor the succession, which is highly disrupted by faulting, was deposited under open-marine conditions probably in a shelf–basin setting. Restricted, very shallow-water seas flooded the Canning Basin and the Merlinleigh–Byro–Irwin sub-basins of the Southern Carnarvon and northern Perth basins and had highly variable oxygen levels and salinities typical of estuarine environments. A similar pattern of warming and bathymetric change is recognized in all studied basins. During the early part of the late Artinskian cool conditions prevailed, with water temperatures 0–4 °C forming sea ice in the Merlinleigh–Byro–Irwin rift. Rapid warming during the latter part of the late Artinskian was accompanied by maximum marine flooding close to the Artinskian–Kungurian boundary. Climatic and bathymetric conditions then allowed carbonate mounds, with larger fusulines and a variety of algae, to develop in the northern part of the rift system, and Tubiphytes, conodonts, and brachiopods with Tethyan affinities to migrate into the marginal-rift basins despite the generally adverse water quality at these depositional sites. Comparison between the stratigraphic record from the East Gondwana interior rift and coeval records from Lhasa and Sibumasu indicate a similar pattern of climate change during the Carboniferous to end Cisuralian. Similar trends probably are present in Eastern Australia although there is confusion over the correlation of some units.
Showing items related by title, author, creator and subject.
Provenance of Permian-Triassic Gondwana Sequence units accreted to the Banda Arc in the Timor region: Constraints from zircon U-Pb and Hf isotopesSpencer, Christopher; Harris, R.; Major, J. (2015)Analysis of zircons from Australian affinity Permian-Triassic units of the Timor region yield age distributions with large age peaks at 230-400. Ma and 1750-1900. Ma, which are similar to zircon age spectra found in rocks ...
Tectonic controls on sediment provenance evolution in rift basins: Detrital zircon U–Pb and Hf isotope analysis from the Perth Basin, Western AustraliaOlierook, Hugo; Barham, Milo; Fitzsimons, Ian; Timms, Nicholas Eric; Jiang, Q.; Evans, N.; McDonald, B. (2019)© 2018 The role of tectonics in controlling temporal and spatial variations in sediment provenance during the evolution of extensional basins from initial rifting to continental breakup and passive margin development are ...
Shi, X.; Kirby, Jon; Yu, C.; Jiménez-Díaz, A.; Zhao, J. (2017)As a proxy for long-term lithospheric strength, detailed information on lateral effective elastic thickness (Te) variations can aid in understanding the distribution pattern of surface deformation and its response to ...