Abstract

Relatively successive sequences of Late Mesozoic are preserved and exposed in Luxi Uplift (LU), eastern North China block (NCB), which is an important region to study the late Mesozoic tectonic evolution of the eastern NCB. In this study, in situ U–Pb ages and Hf isotopic analyses on detrital zircons from the sandstones of Jurassic Fangzi and Santai Formations in LU combining the analysis of sandstone detrital modes were performed, with an aim to trace the Jurassic sediment provenances and the tectonic–paleogeographic configuration of eastern NCB. Three sandstone samples (one from Fangzi Formation and two from Santai Formation) have very similar U–Pb age spectrums which can be divided into three major groups: Phanerozoic (I), Paleoproterozoic (II), and Neoarchean (III). Detrital zircons of Group II and Group III broadly match the age spectra of the basement of NCC which exposed extensively in the northern part. No middle Neoproterozoic magmatic zircons or Triassic metamorphic zircons were found in this study, ruling out the clastic provenance transported from the Sulu orogen to LU. Dominant zircon populations of Group Iare Late Paleozoic (250–393 Ma) recording the corresponding magmatic activities which are not found both in LU and its peripheral tectonic terranes, but can be well compared with that of the northern NCB (NNCB) and the Xing-Meng Orogenic Belt (XMOB). Furthermore, Hf isotope compositions of the Phanerozoic detrital zircons can be distinctly divided into two clusters with εHf(t) values ranging from −1.0 to +12.7 and −21.9 to −3.0, respectively resemble those from the XMOB and NCB (mainly from NNCB). Sandstone detrital modes analysis indicates the provenance came from the areas that have been eroded deeply to expose the basement rocks which accords with the tectonic setting of the NNCB. This research proposes that an evident mountain or provenance region once increasingly developed along NNCB during Early to Late Jurassic (182–155 Ma) due to the continuous collision of the Siberia and North China–Mongolian plates, easily shed mass clastic materials southward into the inner NCB and became the major provenance of Jurassic sediments in LU.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.