Triassic sandstone petrology of Tasmania: evidence for a Tasmania-Transantarctic basin

• Published in: Papers and Proceedings of the Royal Society of Tasmania
• Main Authors: Collinson, JW, Eggert, JT, Kemp, NR
• Format: Article in Journal/Newspaper
• Language: English
• Published: 1990
• Subjects: Royal Society of Tasmania; RST; Van Diemens Land; natural history; science; ecology; taxonomy; botany; zoology; geology; geography; papers & proceedings; Australia; UTAS Library; Antarctic; Victoria Land; Transantarctic Mountains; Pacific; Antarc*; Antarctica
• Online Access: https://eprints.utas.edu.au/13787/; https://eprints.utas.edu.au/13787/4/1990-collinson-triassic-sandstone.pdf

Similar fluvial sequences of Triassic age occur in Tasmania and the Transantarctic Mountains of Victoria Land. The Tasmanian reference section at Poatina consists of Lower Triassic quartzose fluvial sandstones overlain by Middle and Upper Triassic volcaniclastic fluvial sandstones and shale containing coal. Similar, but less wel1-exposed sequences, occur in many places in Tasmania and in southern Victoria Land. The hypothetical Tasmania-Transantarctic basin was similar in scale, configuration, and history to the Sydney foreland basin. Palaeocurrent data suggest that streams flowed along the axis of the basin from Antarctica to Tasmania. Lower Triassic sandstones were deposited by braided streams, but Middle and Upper Triassic stream deposits change from braided to meandering downstream towanl Tasmania. Quartzose sandstones in the Lower Triassic were derived from northwestern Tasmania and the East Antarctic craton. The source of volcaniclastic sandstones in the Middle and Opper Triassic was a calcalkaline volcanic arc along the palaeo-Pacific margin.