Movement History of the Microcontinents from the Tibetan Plateau Based on Paleomagnetic Results with Sufficient Sampling Units.

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Bibliographic Details
Title:	Movement History of the Microcontinents from the Tibetan Plateau Based on Paleomagnetic Results with Sufficient Sampling Units.
Authors:	Ma, Yiming¹ (AUTHOR) maym@cug.edu.cn, Ruan, Weimin² (AUTHOR), Niu, Chao¹ (AUTHOR), Yang, Tianshui³ (AUTHOR)
Source:	Journal of Earth Science. Oct2022, Vol. 33 Issue 5, p1072-1080. 9p.
Subject Terms:	Confidence intervals, Statistical sampling, *Eocene Epoch
Geographic Terms:	Lhasa (China), Tibetan Plateau
Abstract:	Paleomagnetic results cannot be applied in global and regional tectonic reconstructions unless the paleosecular variation has been adequately averaged. However, how many sampling sites and samples are enough to calculate a reliable paleopole remains debated. Based on the relation among the sampling sites N, the precision parameter k, the virtual geomagnetic pole scatter s, and the confidence limit A95 of the paleopole, we find that 20 sites (samples) or more are required to yield a paleopole with an A95 ≈ 5° based on a review of available paleomagnetic results from the Lhasa, Qiangtang and Tethyan Himalaya. Random samplings of Jurassic virtual geomagnetic poles from the Sangri area show that the Fisher mean pole with neglectable angle deviation can be obtained when sampling sites increase to 20. High-quality paleomagnetic results, with sites/samples number N/n ⩾ ∼20–30, show that the Qiangtang, Lhasa, and Tethyan Himalaya moved northward in the Late Permian-Middle Triassic, Jurassic, and Cretaceous, respectively, and then accreted to Asia in the Late Triassic, Late Jurassic-Early Cretaceous and Paleocene-Early Eocene, respectively. [ABSTRACT FROM AUTHOR]
Database:	Energy & Power Source

Description
Abstract:	Paleomagnetic results cannot be applied in global and regional tectonic reconstructions unless the paleosecular variation has been adequately averaged. However, how many sampling sites and samples are enough to calculate a reliable paleopole remains debated. Based on the relation among the sampling sites N, the precision parameter k, the virtual geomagnetic pole scatter s, and the confidence limit A95 of the paleopole, we find that 20 sites (samples) or more are required to yield a paleopole with an A95 ≈ 5° based on a review of available paleomagnetic results from the Lhasa, Qiangtang and Tethyan Himalaya. Random samplings of Jurassic virtual geomagnetic poles from the Sangri area show that the Fisher mean pole with neglectable angle deviation can be obtained when sampling sites increase to 20. High-quality paleomagnetic results, with sites/samples number N/n ⩾ ∼20–30, show that the Qiangtang, Lhasa, and Tethyan Himalaya moved northward in the Late Permian-Middle Triassic, Jurassic, and Cretaceous, respectively, and then accreted to Asia in the Late Triassic, Late Jurassic-Early Cretaceous and Paleocene-Early Eocene, respectively. [ABSTRACT FROM AUTHOR]
ISSN:	1674487X
DOI:	10.1007/s12583-022-1721-2