Structural records of the late Cretaceous-Cenozoic extension in eastearn china and the kinematics of the southern Tan-Lu and Qinling Fault Zone (Anhui and Shaanxi provinces, PR China)

J.L. Mercier (1) , P. Vergely (1) , Y.Q. Zhang (2, 3) , M.J. Hou (4) , O Bellier (5) , Y.M. Wang (4)

1 IDES - Interactions et dynamique des environnements de surface
2 Institute of Geomechanics
3 Department of Earth Sciences [Nanjing]
4 Institute of Geology
5 CEREGE - Centre européen de recherche et d'enseignement des géosciences de l'environnement

Our study of the Late Cretaceous-Cenozoic extension in Eastern China is a kinematic analysis of faults (≈ 1500 striated fault data, 175 stress solutions at 90 sites) that has permitted us to separate stress fields belonging to six tectonic events. A WNW-ESE extension (1) has affected Eastern China from the Campanian to the Late Palaeocene-Early Ypresian. Under this extension, the Qinling (QLFZ) and Southern Tan-Lu (STLFZ) Fault Zones have been dextral transtensional fault zones. A first transpressional event (2) (NNE-SSW shortening) has occurred during the Late Ypresian-Lower Lutetian; the QLFZ and the STLFZ have been dextral transpressional fault zones. A NE-SW extension (3) has affected the Weihe graben during the Palaeogene; after a second transpressional event (4), the NE-SW extension (5) has been rejuvenated during the Late Miocene and the QLFZ has been a normal fault zone again and the STLFZ a sinistral transtensional fault zone; synrift subsidence has occurred in the Weihe graben. The second transpressional event (4) (WNW-ESE shortening) has occurred during the Late Oligocene-Early Miocene, during a period of uplifting and exhumation. At that time, the STLFZ and the QLFZ have become sinistral transpressional fault zones. A period of extension (6) has taken place during the Late Pliocene-Quaternary; the extensional direction has trended ≈ NNW-SSE; during this event, the QLFZ has been a sinistral transtensional fault zone and the STLFZ a dextral transtensional fault zone. These results are compared with those previously published in order to evaluate the regional significance of these tectonic events.

Domains: Earth Sciences

J.L. Mercier, P. Vergely, Y.Q. Zhang, M.J. Hou, O Bellier, et al.. Structural records of the late Cretaceous-Cenozoic extension in eastearn china and the kinematics of the southern Tan-Lu and Qinling Fault Zone (Anhui and Shaanxi provinces, PR China). Tectonophysics, 2013, 582:, pp.50-75 (IF 2,433). ⟨hal-00738172⟩