YANG W T,ZHU J K,FU Q. Detrital zircon U-Pb chronology and provenance analysis from the first member of Ordovician Majiagou Formation in the southern North China[J]. Journal of Henan Polytechnic University( Natural Science), doi: 10.16186/j.cnki.1673-9787.2024120064.

doi: 10.16186/j.cnki.1673-9787.2024120064

Received：2024-12-28

Revised： 2025-04-24

Online： 2026-04-20

Detrital zircon U-Pb chronology and provenance analysis from the first member of Ordovician Majiagou Formation in the southern North China

Yang Wentao ¹ ，Zhu Jinkun ²，Fu Qiang²

（1.Henan International Joint Laboratory of Biogenic Traces and Sedimentary Minerals, Henan Polytechnic University，Jiaozuo 454000，Henan，China； 2. School of Resources and Environment, Henan Polytechnic University Jiaozuo 454000 ，Henan ，China）

Abstract: Objectives To explore the tectonic evolution process of the North Qinling Orogenic Belt during the Early Ordovician period,Methods based on the field geological survey work, the detrital zircon U-Pb chronology analysis was carried out on the first member of the Majiagou Formation in the Jiaozuo area of the southern North China. Results The results show that the first member of the Majiagou Formation has two detrital zircon age groups, namely the Neoarchean-Paleoproterozoic and the Early Paleozoic, and three age peaks are formed: 483 Ma, 1840 Ma, and 2445 Ma. Among them, the Neoarchean-Paleoproterozoic (~1840 Ma, ~2445 Ma) detrital zircons are derived from the basement of the North China Craton, while the Early Paleozoic (483 Ma) detrital zircons are from the North Qinling Orogenic Belt. The results of the provenance analysis are consistent with the paleogeographical features, suggesting that the arc-continent collision orogenic belt activity occurred in the North Qinling Orogenic Belt during the Early Ordovician period. Before the Early Ordovician period, the Kuanping Ocean had not been completely closed, and due to the isolation of the ocean basin, the Erlangping island arc terrane was unable to transport detrital materials to the North China Basin; during the Early Ordovician period, due to the closure of the Kuanping Ocean, the arc-continent collision between the Erlangping island arc terrane and North China occurred, enabling the detrital materials from the Erlangping island arc to smoothly enter the Early Ordovician strata of the North China Basin. We have realized that the detrital zircon ages of the sandstone in the first member of the Ordovician Majiagou Formation in the southern North China indicate that the provenance of the southern part of the North China Basin during the Early Ordovician may be provided by the North Qinling, and the detrital zircon ages of the Late Paleozoic do not appear in the chronological data. The detrital zircon ages of the Late Paleozoic are the characteristic ages of the Inner Mongolia Uplift, and the absence of this age peak may support the fact that the southward subduction of the Paleo-Asian Ocean was not intense. The age peaks of the Neoarchean-Paleoproterozoic detrital zircons are the characteristic ages of the basement of the North China Craton, and the provenance forming these two age peaks may be the products of the recycling of the North China Craton. Conclusions Before the Early Ordovician, the Kuanping Ocean had not yet completely closed, and the Erlangping island arc was unable to supply clastic materials to the North China Basin due to the isolation of the ocean basin. During the Early Ordovician, the Erlangping island arc terrane was accreted to the southern margin of the North China Craton, making the Erlangping island arc an important provenance for the first member of the Majiagou Formation in southern North China.

Key words：sediment source, Majiagou Formation, detrital zircon , Kuanping Ocean, Erlangping island arc