HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

Paleoproterozoic tectonic evolution of the Trans-North China Orogen: toward a comprehensive model.

Abstract : In this contribution we present a reconstruction of the overall lithotectonic architecture, from inner zones to external ones, of the Paleoproterozoic Trans North China Orogen, within the North China Craton. Moreover, forward thermobarometrical modeling on a kyanite-bearing gneiss yields a reliable prograde P-T-t-D path. In addition, 40Ar/39Ar dating on rocks from distinct litho-tectonic units helps us to distinguish several tectono-metamorphic events during the orogenic development. Considering these results, we propose a geodynamic model involving three cratonic blocks, namely the Western, Fuping and Eastern Blocks, separated by two oceans, the Lüliang and Taihang Oceans. The opening of oceanic basins occurred around 2.2-2.3 Ga. After the westward subductions of oceanic lithosphere, the Trans-North-China Orogen was built up through a polyphase tectonic evolution within the period 1900-1800 Ma. The first event (D1) corresponded to the emplacement of lower and upper nappes herein called the Orthogneiss-and-Volcanites Unit (OVU) and the Low-Grade-and-Mafic Unit (LGMU), respectively. The syn-metamorphic D1 deformation (1880 ± 10 Ma) is characterized by a NW-SE stretching and mineral lineation with a top-to-the SE sense of shear. During ongoing compression of the thickening orogenic crust, a second deformation event D2 (1850 ± 10 Ma) was responsible for (1) syn-anatectic lateral flow and exhumation of the orogenic root and (2) folding of the middle and upper parts of the orogenic wedge that consequently acquired a fan-type geometry. The late D3 (1830 ± 10 Ma) and D4 (1810 ± 10 Ma) events are related to late-orogenic normal and strike-slip shearing, respectively. In our present state of knowledge, the Paleoproterozoic Trans-North China Orogen might be regarded as the assemblage of two continent-continent collisional belts, both of which are characterized by nappe stacking accommodated by top-to-the E/SE ductile shearing. Continental subduction, crustal thickening, partial melting of overthickened crust, exhumation of HP rocks and deposition of syn-orogenic detrital basins are typical features of modern collisional-type orogens.
Complete list of metadata

Cited literature [123 references]  Display  Hide  Download

https://hal-insu.archives-ouvertes.fr/insu-00628119
Contributor : Nathalie Pothier Connect in order to contact the contributor
Submitted on : Monday, January 2, 2012 - 2:40:32 PM
Last modification on : Thursday, January 13, 2022 - 11:58:03 AM
Long-term archiving on: : Tuesday, April 3, 2012 - 2:20:08 AM

File

Trap-PrecambrianResearch-2011....
Publisher files allowed on an open archive

Identifiers

Citation

Pierre Trap, Michel Faure, Wei Lin, Nicole Le Breton, Patrick Monié. Paleoproterozoic tectonic evolution of the Trans-North China Orogen: toward a comprehensive model.. Precambrian Research, Elsevier, 2012, 222-223, pp.191-211. ⟨10.1016/j.precamres.2011.09.008⟩. ⟨insu-00628119⟩

Share

Metrics

Record views

294

Files downloads

573