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Research output: Contribution in Book/Report/Proceedings - With ISBN/ISSN › Chapter (peer-reviewed) › peer-review
Research output: Contribution in Book/Report/Proceedings - With ISBN/ISSN › Chapter (peer-reviewed) › peer-review
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TY - CHAP
T1 - A geomagnetic polarity timescale for the Permian, calibrated to stage boundaries
AU - Hounslow, Mark William
AU - Balabanov, Yuri P.
PY - 2018/3/7
Y1 - 2018/3/7
N2 - The reverse polarity Kiaman Superchron has strong evidence for at least three, or prob ably four, normal magnetochrons during the early Permian. Normal magnetochrons are during the early Asselian (base CI1r.1n at 297.94+0.33 Ma), late Artinskian (CI2n at 281.24+2.3 Ma), mid-Kungurian (CI3n at 275.86+2.0 Ma) and Roadian (CI3r.an at 269.54+1.6 Ma). The mixed-polarity Illawarra Superchron begins in the early Wordian at 266.66+0.76 Ma. The Wordian–Capitanian interval is biased to normal polarity, but the basal Wuchiapingian begins the beginning of a significant reverse polarity magnetochron LP0r, with an overlying mixed-polarity interval through the later Lopingian. No significant magnetostratigraphic data gaps exist in the Permian geomagnetic polarity record. The early Cisuralian magnetochrons are calibrated to a succession of fusulinid zones, the later Cisuralian and Guadalupian to a conodont and fusulinid biostratigraphy, and Lopingian magnetochrons to conodont zonations. Age calibration of the magnetochrons is obtained through a Bayesian approach using 35 radiometric dates, and 95% confidence intervals on the ages and chron durations are obtained. The dating control points are most numerous in the Gzhelian–Asselian, Wordian and Changhsingian intervals. This significant advance should provide a framework for better correlation and dating of the marine and non-marine Permian
AB - The reverse polarity Kiaman Superchron has strong evidence for at least three, or prob ably four, normal magnetochrons during the early Permian. Normal magnetochrons are during the early Asselian (base CI1r.1n at 297.94+0.33 Ma), late Artinskian (CI2n at 281.24+2.3 Ma), mid-Kungurian (CI3n at 275.86+2.0 Ma) and Roadian (CI3r.an at 269.54+1.6 Ma). The mixed-polarity Illawarra Superchron begins in the early Wordian at 266.66+0.76 Ma. The Wordian–Capitanian interval is biased to normal polarity, but the basal Wuchiapingian begins the beginning of a significant reverse polarity magnetochron LP0r, with an overlying mixed-polarity interval through the later Lopingian. No significant magnetostratigraphic data gaps exist in the Permian geomagnetic polarity record. The early Cisuralian magnetochrons are calibrated to a succession of fusulinid zones, the later Cisuralian and Guadalupian to a conodont and fusulinid biostratigraphy, and Lopingian magnetochrons to conodont zonations. Age calibration of the magnetochrons is obtained through a Bayesian approach using 35 radiometric dates, and 95% confidence intervals on the ages and chron durations are obtained. The dating control points are most numerous in the Gzhelian–Asselian, Wordian and Changhsingian intervals. This significant advance should provide a framework for better correlation and dating of the marine and non-marine Permian
U2 - 10.1144/SP450.8
DO - 10.1144/SP450.8
M3 - Chapter (peer-reviewed)
SN - 9781786202826
VL - 450
T3 - Geological Society, London, Special Publications
SP - 61
EP - 103
BT - The Permian timescale
A2 - Lucas, Spencer
A2 - Shen, Shugong. Z.
PB - Geological Society of London
CY - London
ER -