Paleozoic to Early Mesozoic Tectonics of North China Craton

The North China Craton (NCC) started its Paleozoic evolution from ca. 520 Ma when Gondwana assembled in its peak tectonism. The Middle Cambrian developed in margins of the NCC on older strata or basement rocks. Then the marine environment expansion and it

  • PDF / 2,216,345 Bytes
  • 14 Pages / 595.276 x 790.866 pts Page_size
  • 107 Downloads / 208 Views

DOWNLOAD

REPORT


18

Yue Zhao, Mingguo Zhai, and Shuan-Hong Zhang

Abstract

The North China Craton (NCC) started its Paleozoic evolution from ca. 520 Ma when Gondwana assembled in its peak tectonism. The Middle Cambrian developed in margins of the NCC on older strata or basement rocks. Then the marine environment expansion and its extensive invasion led to the late Middle Cambrian marine deposits, the Mantou Formation and afterwards occurred throughout the NCC. New results of the Bainaimiao arc belt, north to the northern NCC indicated that the arc was active from 520 Ma and lasted to 420 Ma, which could extend to east Siping in NE China. Along the southern edge of the NCC the northward subduction of the Shangdan Ocean was operated during ca. 514–420 Ma. Marine regression occurred postdated the Majiagou phase in Middle Ordovician in most parts of the NCC. Recently in the northern NCC some Devonian plutons and volcanic rocks were recognized. The Late Carboniferous sedimentary sequence with the ‘G’ layer of bauxites at its bottom is overlain disconformably upon the Middle Ordovician limestone. The bauxites were derived mainly from ashes produced by volcanism mainly in the Inner Mongolia Paleo-uplift (IMPU) during Paleozoic period, particularly in latest Early Carboniferous to Early Permian when the northern margin of the NCC evolved as an Andean-style active continental margin. The sequence is mainly clastic formations, composed of coal-bearing sandstones and siltstones interlayered with marine limestone and volcanic ash, which demonstrates that they formed in terrestrial–marine transitional or terrestrial environment with volcanic arc settings. After late Early Permian a terrestrial environment was dominant in the NCC. In the southern NCC and the Qinling Orogenic Belt (QOB) spreading of the Mianlue Ocean between the South China Craton (SCC) and South Qinling Block (SQB) was sustained in Late Paleozoic and the northward subduction– accretion of the Mianlue Ocean was active in Late Paleozoic. In Triassic, the collision between the SCC and SQB along the Mianlue suture resulted in intense shortening and uplift of QOB and HP/UHP metamorphism documented in Hong’an-Dabie-Sulu terranes. Y. Zhao  S.-H. Zhang Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing, 100081, China Y. Zhao (&)  S.-H. Zhang Key Laboratory of Paleomagnetism and Tectonic Reconstruction, Ministry of Land and Resources, Beijing, 100081, China e-mail: [email protected] M. Zhai Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China M. Zhai State Key Laboratory of Geodynamics, Northwest University, Xian, 710069, China © Springer Science+Business Media Singapore 2016 M. Zhai et al. (eds.), Main Tectonic Events and Metallogeny of the North China Craton, Springer Geology, DOI 10.1007/978-981-10-1064-4_18

453

454

Y. Zhao et al.

Meanwhile in the northern NCC, significant changes in tectonic deformation and magmatism occurred in Late Triassic. In the Panshan region, the northern NCC, intensive regional folding and