Rights statement: An edited version of this paper was published by AGU. Copyright 2020 American Geophysical Union. Li, S., van Hinsbergen, D. J. J., Shen, Z., Najman, Y., Deng, C., & Zhu, R. ( 2020). Anisotropy of magnetic susceptibility (AMS) analysis of the Gonjo Basin as an independent constraint to date Tibetan shortening pulses. Geophysical Research Letters, 47, e2020GL087531. https://doi.org/10.1029/2020GL087531
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Anisotropy of Magnetic Susceptibility (AMS) Analysis of the Gonjo Basin as an Independent Constraint to Date Tibetan Shortening Pulses
AU - Li, Shihu
AU - van Hinsbergen, D.J.J.
AU - Shen, Zhongshan
AU - Najman, Yani
AU - Deng, Chenglong L.
AU - Zhu, Rixiang X.
N1 - An edited version of this paper was published by AGU. Copyright 2020 American Geophysical Union. Li, S., van Hinsbergen, D. J. J., Shen, Z., Najman, Y., Deng, C., & Zhu, R. ( 2020). Anisotropy of magnetic susceptibility (AMS) analysis of the Gonjo Basin as an independent constraint to date Tibetan shortening pulses. Geophysical Research Letters, 47, e2020GL087531. https://doi.org/10.1029/2020GL087531
PY - 2020/4/28
Y1 - 2020/4/28
N2 - The Tibetan Plateau accommodated major upper crustal shortening during Indian Plate oceanic and continental lithosphere subduction. Deciphering whether shortening was continuous or episodic, and how it correlates to major geodynamic changes is challenging. Here we apply anisotropy of magnetic susceptibility (AMS), a sensitive synsedimentary strain indicator, to a ~3 km thick magnetostratigraphically dated sedimentary section (69–41.5 Ma) in eastern Tibet. AMS shows “earliest deformation” fabrics from 69–52 Ma, followed by a sudden change to “pencil structure” fabrics with increasing anisotropy degree at ~52 Ma, dating a sudden increased synsedimentary shortening strain. This change coincides with enhanced sedimentation rates and synsedimentary vertical‐axis rotations of the Gonjo Basin, suggesting a causal link to a marked India‐Asia convergence rate deceleration. We show that AMS analysis provides a strong tool to distinguish between climatic and tectonic causes of sedimentological change and is an asset in identifying discrete tectonic pulses in intensely deformed terrane.
AB - The Tibetan Plateau accommodated major upper crustal shortening during Indian Plate oceanic and continental lithosphere subduction. Deciphering whether shortening was continuous or episodic, and how it correlates to major geodynamic changes is challenging. Here we apply anisotropy of magnetic susceptibility (AMS), a sensitive synsedimentary strain indicator, to a ~3 km thick magnetostratigraphically dated sedimentary section (69–41.5 Ma) in eastern Tibet. AMS shows “earliest deformation” fabrics from 69–52 Ma, followed by a sudden change to “pencil structure” fabrics with increasing anisotropy degree at ~52 Ma, dating a sudden increased synsedimentary shortening strain. This change coincides with enhanced sedimentation rates and synsedimentary vertical‐axis rotations of the Gonjo Basin, suggesting a causal link to a marked India‐Asia convergence rate deceleration. We show that AMS analysis provides a strong tool to distinguish between climatic and tectonic causes of sedimentological change and is an asset in identifying discrete tectonic pulses in intensely deformed terrane.
M3 - Journal article
VL - 47
JO - Geophysical Research Letters
JF - Geophysical Research Letters
SN - 0094-8276
IS - 8
M1 - e2020GL087531
ER -