Provenance and Implication of Carboniferous–Permian Detrital Zircons from the Upper Paleozoic, Southern Ordos Basin, China: Evidence from U-Pb Geochronology and Hf Isotopes

Ziwen Jiang,Shangwei Ma,Xinyou Hu,Yuhua Hu,Jinglan Luo,Xinshe Liu,Yundong Hou,Liyong Fan

doi:10.3390/min10030265

Abstract

Carboniferous–Permian detrital zircons are recognized in the Upper Paleozoic of the whole Ordos Basin. Previous studies revealed that these Carboniferous–Permian zircons occurred in the Northern Ordos Basin mainly originated from the Yinshan Block. What has not been well documented until now is where this period’s zircons in the Southern Ordos Basin came from, and very little discussion about their provenance. To identify the provenance of the detrital zircons dating from ~350 to 260 Ma, five sandstone samples from the Shan 1 Member of Shanxi Formation and eight sandstone samples from the He 8 Member of Shihezi Formation were analyzed for detrital zircon U-Pb age dating and in situ Lu-Hf isotopic compositions. The results indicate that the two age clusters of 520–378 Ma and ~350–260 Ma in the Southern Ordos Basin most likely derived from the North Qinling Orogenic Belt–North Qilian Orogenic Belt and the North Qinling Orogenic Belt, respectively. Furthermore, we propose that the zircons aging ~320–260 Ma are representative of the important tectonothermal events occurred in the North Qinling Orogenic Belt during the Late Paleozoic.

Highlights

The Ordos Basin, located in the southwest part of the North China Craton (Figure 1), is the second largest sedimentary basin in China [1] and is over 250,000 km2 in size [2]
Paleozoic were from southwest to northeast, southeast to northwest and south to north, and the main source areas were the North Qinling Orogenic Belt (NQinOB) and North Qilian Orogenic Belt (NQiOB)
In order to study the potential relationship between zircon age and grain size, the grain size and shape parameters of each dated zircon were measured and used to calculate the equivalent spherical diameter (ESD) [50]

Summary

Introduction

The Ordos Basin, located in the southwest part of the North China Craton (Figure 1), is the second largest sedimentary basin in China [1] and is over 250,000 km in size [2]. Abundant oil and gas resources occur in the Upper Paleozoic clastic rocks of the basin. The Carboniferous–Permian (~350–260 Ma) detrital zircons are widely distributed in the Upper. Some studies have investigated the source of the Upper. Paleozoic in the Southern Ordos Basin (SOB) [4,5,6,7,8,9,10,11,12]. Sedimentary facies [4,7,8,9] in the SOB suggest that the source supplying directions of the Upper. Paleozoic were from southwest to northeast, southeast to northwest and south to north, and the main source areas were the North Qinling Orogenic Belt (NQinOB) and North Qilian Orogenic Belt (NQiOB). The provenance of the ~350–260 Ma detrital zircons in the SOB was poorly defined Previous studies that used the methods of analyzing sandstone detrital component [4,5,6,7,9,10,11], sandstone composition [4,5,6,7,9,10,11], heavy mineral component [4,5,7,8,9,11], whole rock geochemistry [4,6], and the analyses of the paleocurrent [4,5,8,9,10,11]

Results

Discussion

Conclusion