Lithology and U–Pb Geochronology of Basement of Cenozoic Yitong Basin in Northeastern China: Implication for Basin Architecture and New Horizon of Deep Natural Gas Exploration

Zhenlin Chen,Yu Zou,Hongbo Miao,Lianfu Mei,Hua Wang,Shu Jiang

doi:10.3390/min8120559

Abstract

The lithology and formation age of basement rocks are significant for the understanding of the nature of basin architecture, evolution and the potential of hydrocarbons of a basin. In this study, the basement lithology of the Cenozoic Yitong Basin is investigated through the petrological analysis of cores, cuttings, and thin sections. The results suggest that the basement rocks of the Yitong Basin are mostly composed of unique igneous rocks that are different from nearby basins’ sedimentary and metamorphic basement. The igneous rocks are dominated by intrusive monzonite granite and alkali feldspar granite. Additionally, U–Pb zircon geochronology of basement samples by LA-ICP-MS and the geological interpretation of apparent resistivity data indicate that the igneous basement in major part of the basin was mainly formed by a lateral intrusion of granite into the Permian sedimentary stratum in the Yanshanian period from 177 to 170 Ma. The results also reveal the two-layer basin architecture with coal-bearing Carboniferous–Permian strata below the igneous basement covered with Tertiary sediments, thus providing a new geologic horizon for deep natural gas exploration in the older coal-bearing sedimentary rocks beneath the current igneous basement.

Highlights

An increasing number of studies have revealed that, during the Late Jurassic, the tectonic activity in eastern Asia changed drastically from a regime of strong intracontinental compressional orogenesis and crustal thickening to one of the strong intracontinental extensional rifting and lithospheric thinning [1]
The distributions of the entire LA-ICP-MS data obtained from the 10 zircon samples in this study indicated that these zircons were densely distributed on the concordant curve (Figure 4), with only a minority of the zircons deviating slightly from the curve
A series of faulted basins were developed in eastern China during the Yanshanian period, such as the Songliao and Bohai Bay Basins, which closely neighbor the Yitong Basin (YB)

Summary

Introduction

An increasing number of studies have revealed that, during the Late Jurassic, the tectonic activity in eastern Asia changed drastically from a regime of strong intracontinental compressional orogenesis and crustal thickening to one of the strong intracontinental extensional rifting and lithospheric thinning [1]. This transformation of tectonic deformation was closely related to the subduction of the Pacific Plate under the Asian continent [2,3,4]. Oiltoand resources and have their been consistently ranked the proven first and second places reserves and production, respectively, among all production haveinbeen in the Songliao andfor

Methods

Results

Discussion

Conclusion