Calibrating the middle and late Permian palynostratigraphy of Australia to the geologic time-scale via U–Pb zircon CA-IDTIMS dating

Autor: James L. Crowley, Robert S. Nicoll, David C. Champion, John R. Laurie, Arthur J. Mory, G.R. Wood, Tegan Smith, E.K. Holmes, S. Bodorkos, John Backhouse, Daniel Mantle
Rok vydání: 2016
Předmět:
Zdroj: Australian Journal of Earth Sciences. 63:701-730
ISSN: 1440-0952
0812-0099
DOI: 10.1080/08120099.2016.1233456
Popis: The advent of chemical abrasion-isotope dilution thermal ionisation mass spectrometry (CA-IDTIMS) has revolutionised U–Pb dating of zircon, and the enhanced precision of eruption ages determined on volcanic layers within basin successions permits an improved calibration of biostratigraphic schemes to the numerical time-scale. The Guadalupian and Lopingian (Permian) successions in the Sydney, Gunnedah, Bowen and Canning basins are mostly non-marine and include numerous airfall tuff units, many of which contain zircon. The eastern Australian palynostratigraphic scheme provides the basis for much of the local correlation, but the present calibration of this scheme against the numerical time-scale depends on a correlation to Western Australia, using rare ammonoids and conodonts in that succession to link to the standard global marine biostratigraphic scheme. High-precision U–Pb zircon dating of tuff layers via CA-IDTIMS allows this tenuous correlation to be circumvented—the resulting direct calibratio...
Databáze: OpenAIRE