Measuring the ‘Great Unconformity’ on the North China Craton using new detrital zircon age data

Abstract

Abstract New detrital zircon ages confirm that the Neoproterozoic strata of the southeastern North China Craton (NCC) are mostly of early Tonian age, but that the Gouhou Formation, previously assigned to the Tonian, is Cambrian in age. A discordant hiatus of >150–300 myr occurs across the NCC, spanning most of the late Tonian, Cryogenian, Ediacaran and early Cambrian periods. This widespread unconformable surface is akin to the Great Unconformity seen elsewhere in the world and highlights a major shift in depositional style from largely erosional, marked by low rates of net deposition, during the mid- to late Neoproterozoic to high rates of transgressive deposition during the mid- to late Cambrian. The age spectra for the southeastern NCC and northern India are consistent with a provenance affinity linking the NCC and East Gondwana by c. 510 Ma. Supplementary material: Sample descriptions, sampling GPS locations and a compiled dataset of detrital zircon U–Pb LA-ICP-MS dating results are available at https://doi.org/10.6084/m9.figshare.c.3571119