Early Jurassic palaeoenvironments in the Surat Basin, Australia – marine incursion into eastern Gondwanaстатья из журнала
Аннотация: Abstract Interpretations of palaeodepositional environments are important for reconstructing Earth history. Only a few maps showing the Jurassic depositional environments in eastern Australia currently exist. Consequently, a detailed understanding of the setting of Australia in Gondwana is lacking. Core, wireline logs, two‐dimensional and three‐dimensional seismic from the Precipice Sandstone and Evergreen Formation in the Surat Basin have been used to construct maps showing the evolution of depositional environments through the Early Jurassic. The results indicate the succession consists of three third‐order sequences (Sequence 1 to Sequence 3) that were controlled by eustatic sea level. The lowstand systems tract in Sequence 1 comprises braidplain deposits, confined to a fairway that parallels the basin centre. The strata were initially deposited in two sub‐basins, with rivers flowing in different orientations in each sub‐basin. The transgressive systems tract of Sequence 1 to lowstand systems tract of Sequence 3 is dominated by fluvio–deltaic systems infilling a single merged basin centre. Finally, the transgressive and highstand systems tracts of Sequence 3 show nearshore environments depositing sediment into a shallow marine basin. In the youngest part of this interval, ironstone shoals are the most conspicuous facies, the thickness and number of which increase towards the north and east. This study interprets a corridor to the open ocean through the Clarence–Moreton Basin, or the Carpentaria and Papuan basins, evidence of which has been eroded. These results challenge a commonly held view that eastern Australia was not influenced by eustasy, and propose a more dynamic palaeogeographic setting comprising a mixture of fluvial, deltaic and shallow marine sedimentary environments. This work can be used to unravel the stratigraphic relationships between Mesozoic eastern Australian basins, or in other basins globally as an analogue for understanding the complex interplay of paralic depositional systems in data poor areas.
Год издания: 2019
Авторы: Andrew D. La Croix, Jianhua He, Valeria Bianchi, Jiahao Wang, Sebastián González, Jim Undershultz
Издательство: Wiley
Источник: Sedimentology
Ключевые слова: Geological and Geophysical Studies, Geological formations and processes, Hydrocarbon exploration and reservoir analysis
Другие ссылки: Sedimentology (HTML)
Research Commons (The University of Waikato) (PDF)
Research Commons (The University of Waikato) (HTML)
Research Commons (The University of Waikato) (PDF)
Research Commons (The University of Waikato) (HTML)
Открытый доступ: green
Том: 67
Выпуск: 1
Страницы: 457–485