Detrital zircon analysis of the Mesozoic strata in the northern Ordos Basin: Revealing the source‐to‐sink relationships and tectonic settings

Abstract

The Geo‐chronology of the Mesozoic sequences from the northern Ordos Basin provides an excellent window for understanding the source‐to‐sink analysis and tectonic settings. In this study, nine groups of detrital zircon U–Pb ages from the Middle Triassic to Lower Cretaceous strata of the northern Ordos Basin are presented. Three dominant age groups are revealed through the kernal density estimation: ca. 2,300 ~ 2,500 Ma (Siderian), ca. 2,050 ~ 1,800 Ma (Orosirian), and ca. 358.9 ~ 298.9 Ma (Carboniferous). Significant differences are distinguished according to multidimensional scaling analysis and cumulative distribution function. The Middle Triassic sample is the closest to the Yin Mts and the upper Triassic and lower Jurassic samples have significant similarities with the Jining area. The samples YA‐1 and ZL‐1 from the Middle Jurassic sequences are the closest to the Daqing Mts (DQS) and Wula Mts (WLS), respectively. The sample ZL‐1 is the second closest to the DQS. The sample YJ‐1 from the Lower Cretaceous sequences has apparent affinities with multiple resources, including the DQS, WLS and samples EM‐1 and AD‐1, while the sample LH‐1 only resembles the sample YA‐1. Overall, the northern Ordos Basin experienced three stages of transformations in the source areas: (a) Southward migration during the Middle Triassic and the Early Jurassic; (b) Westward migration during the Early Jurassic and latest Middle Jurassic; (c) Southward migration during the latest Middle Jurassic, and multiple resources and recycled sediments for the Cretaceous sequences. The transition to the North China Craton's (NCC) extensional tectonic setting was closely related to the transformation from the Palaeo‐Asian Ocean's closure to the Palaeo‐Pacific Plate's subduction during the Early Jurassic. The multiple resources and recycled resources for the Lower Cretaceous sequences were related to the destruction of the NCC.