TY - JOUR
T1 - Cenozoic paleoaltimetry of the SE margin of the Tibetan Plateau
T2 - Constraints on the tectonic evolution of the region
AU - Li, Shanying
AU - Currie, Brian S.
AU - Rowley, David B.
AU - Ingalls, Miquela
N1 - Funding Information:
We are grateful to Gerry Olack and Albert Colman at the University of Chicago and Daniel Schrag at Harvard University for stable isotope analyses reported in this paper. We thank John Rakovan and Matthew Duley at Miami University for their assistance in the XRD and SEM laboratory. Two anonymous reviewers provided careful and constructive reviews that greatly improved the quality of the manuscript. This work was funded by the National Science Foundation ( EAR-0609756 to Currie and EAR-0609782 and EAR-1111274 to Rowley).
Publisher Copyright:
© 2015 Elsevier B.V.
PY - 2015/12/15
Y1 - 2015/12/15
N2 - An improved understanding of the elevation history of the Tibetan Plateau is crucial in discriminating among the various tectonic models for the evolution of the India-Asia continental collision. We reconstruct the paleoelevation history for three Cenozoic sedimentary basins from SE Tibet and Yunnan, China, to provide more constraints on the tectonic processes for raising the SE margin of the Tibetan Plateau. The results presented here, together with those of previous studies, indicate that (1) the plateau margin of NW Yunnan was near its elevation (~2.6 km) by the latest middle Eocene (~40 Ma); (2) the plateau margin of SE Yunnan reached its current elevation (~1.6 km) by the middle Miocene (~13 Ma). Interpretations of the tectonic processes responsible for this inferred surface uplift of the region are made in the context of well-documented surface geology. We conclude that high landscape (~2.6 km elevation) in NW Yunnan may represent the remnants of the Eocene Tibetan plateau that originally formed in the northeastern Qiangtang Block by crustal thickening associated with the India-Asia continental collision. The near-modern elevation of SE Yunnan since ~13 Ma probably reflects the initiation of lower crustal flow in this area by at least that time. Collectively, our paleoaltimetric interpretations disagree with previously proposed models of middle Miocene to Pliocene crustal flow acting as a sole tectonic process for raising the SE margin of the plateau, but support a protracted history of surface uplift that most likely involved crustal thickening during the Eocene, southeastward extrusion of a portion of Eocene Tibetan plateau during the Oligocene to early Miocene, and lower crustal flow beneath this region since at least the early Miocene.
AB - An improved understanding of the elevation history of the Tibetan Plateau is crucial in discriminating among the various tectonic models for the evolution of the India-Asia continental collision. We reconstruct the paleoelevation history for three Cenozoic sedimentary basins from SE Tibet and Yunnan, China, to provide more constraints on the tectonic processes for raising the SE margin of the Tibetan Plateau. The results presented here, together with those of previous studies, indicate that (1) the plateau margin of NW Yunnan was near its elevation (~2.6 km) by the latest middle Eocene (~40 Ma); (2) the plateau margin of SE Yunnan reached its current elevation (~1.6 km) by the middle Miocene (~13 Ma). Interpretations of the tectonic processes responsible for this inferred surface uplift of the region are made in the context of well-documented surface geology. We conclude that high landscape (~2.6 km elevation) in NW Yunnan may represent the remnants of the Eocene Tibetan plateau that originally formed in the northeastern Qiangtang Block by crustal thickening associated with the India-Asia continental collision. The near-modern elevation of SE Yunnan since ~13 Ma probably reflects the initiation of lower crustal flow in this area by at least that time. Collectively, our paleoaltimetric interpretations disagree with previously proposed models of middle Miocene to Pliocene crustal flow acting as a sole tectonic process for raising the SE margin of the plateau, but support a protracted history of surface uplift that most likely involved crustal thickening during the Eocene, southeastward extrusion of a portion of Eocene Tibetan plateau during the Oligocene to early Miocene, and lower crustal flow beneath this region since at least the early Miocene.
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U2 - 10.1016/j.epsl.2015.09.044
DO - 10.1016/j.epsl.2015.09.044
M3 - Article
AN - SCOPUS:84946843264
SN - 0012-821X
VL - 432
SP - 415
EP - 424
JO - Earth and Planetary Science Letters
JF - Earth and Planetary Science Letters
ER -