FAN Q Q, ZHENG D S, SHUN F B, et al． Identification of Milankovitch cycles and reconstruction of earth-moon system: A case study of the middle and upper members in the Dagushi Formation, Southern margin of the North China Craton［J］. Journal of Henan Polytechnic University( Natural Science)， doi: 10.16186/j.cnki.1673-9787.2025100026.

doi: 10.16186/j.cnki.1673-9787.2025100026

Received：2025-10-02

Revised： 2025-12-03

Online： 2026-04-20

Identification of Milankovitch cycles and reconstruction of earth-moon system: A case study of the middle and upper members in the Dagushi Formation, Southern margin of the North China Craton (Online)

Fan Qiongqi, Zheng Deshun, Sun Fengbo, Li Ting

School of Resources and Environment, Henan Polytechnic University, Jiaozuo 454003, Henan, China

Abstract: Objectives This study aimed to identify the Milankovitch cycles in the early Mesoproterozoic (~1787 Ma) based on cyclostratigraphic evidence, and to calculate the Earth-Moon orbital parameters, including the precession constant k, Earth-Moon distance and day length, in order to reconstruct the evolutionary history of the deep-time Earth-Moon system. Methods With High-resolution Fe and Ti element concentration sequences as paleoclimate proxies, cyclostratigraphic analysis was performed on the middle-upper Dagushi Formation in the Huangbeijiao section, southern margin of the North China Craton, to identify the main astronomical cycles of the early Mesoproterozoic. Due to the lack of accurate radioisotope age constraints, the sedimentation rate could not be precisely estimated from chronostatigraphic data and formation thickness. To improve the reliability of the cyclostratigraphic interpretation, two methods, the Correlation Coefficient Method (COCO) and the Time Scale Optimization Method (TimeOpt), were employed to estimate the average sedimentation rate of the studied stratum. Furthermore, Earth-Moon orbital parameters were estimated via two independent methods: k+ and Bayesian inversion (TimeOptMCMC). Results The average sedimentation rate for the studied stratum is estimated to be 2.36-2.53 cm/kyr. Moreover, spectral analysis reveals that the dominant sedimentary cycles of 10.150 m, 2.200~2.210 m, 0.427~0.436 m, and 0.279~0.355 m correspond to the orbital 405-kyr long eccentricity, 86.50-87.00-kyr short eccentricity, 16.48~17.28-kyr obliquity, and 13.08-14.09-kyr precession cycles, respectively. The k+ approach yielded a precession rate k of 95.8±1.1 arcsec/yr, an Earth-Moon distance of 330 783(+937/-926) km, and a length of day of 17.86(+0.09/-0.08) h, while the TimeOptMCMC approach yields a precession rate k of 92.21±1.6 arcsec/yr, an Earth-Moon distance of 333 885(+1 426/-1,398) km, and a length of day of 18.14(+0.14/-0.12) h. Conclusions Significant Milankovitch cycle signals were recorded in the Dagushi Formation in the Huangbeijiao section, confirming that the sedimentary records in the early Mesoproterozoic Era (~1 787 Ma) were controlled by Milankovitch cycles. The Earth-Moon parameters derived from two independent methods will provide a new evidence for understanding the evolutionary history of the Earth-Moon system during the early Mesoproterozoic Era.

Key words: cyclostratigraphy; Huangbeijiao Section; Dagushi Formation; Earth-Moon System; southern margin of the North China Craton