高校地质学报2024，Vol.30Issue(6)：737-746,10.DOI:10.16108/j.issn1006-7493.2023061
澳大利亚苏拉特盆地中—上侏罗统Walloon煤系旋回地层的天文周期驱动
Astronomical Forcing in the Middle-Upper Jurassic Walloon Coal Measures Cycles in the Surat Basin,Australia
摘要
Abstract
The Walloon coal measures in the Surat Basin,Australia,has a huge amount of coalbed methane(CBM)resources,but the spatial heterogeneity of CBM production capacity varies significantly.Variable characteristics of multiple thin coal seams in the Walloon coal measures,and rapid lateral changes in lithology limit further research on the lateral differences of coal reservoirs.Therefore,fine-scale stratigraphic framework delineation of the Walloon coal measures in the Surat Basin is fundamental for understanding the temporal and spatial differences of coal reservoirs.The S-4 well,which has a complete and continuous sedimentary formation,is used as the main drilling well.Time series analysis of its natural gamma(GR)logging data is used for the cyclostratigraphic study.The power spectrum analysis results show that the Walloon coal measures in the Surat Basin recorded 15 sedimentary cycles of 405 kyr periodicity,and orbital forcing had a significant impact on its depositional process.The long eccentricity,short eccentricity,obliquity,and precession are represented by sedimentary cycles with thickness of 23.9 m,6.3-9.3 m,2.4-2.7 m,and 1.2-1.4 m,respectively.Correlation coefficient analysis indicates that the Walloon coal measures was driven by astronomical cycles at>99%confidence level.Using the zircon CA-TIMS U-Pb age of 162.54±0.05 Ma from the S-4 well coal-bearing tuff as a constraint,an astronomical calibration was performed using a stable 405 kyr cycle to establish an astronomical time scale for the Walloon coal measures.The duration of this formation was determined to be 5.7-6.1 Myr,mainly deposited during the Middle Jurassic Callovian to Late Jurassic Oxfordian.Based on the consistency between time series analysis and identification of cyclic interfaces,combined with the identified sedimentary cycles of 405 kyr periodicity,the Walloon coal measures was divided into 5 third-order sequences and 15 fourth-order sequences,establishing a high-frequency sequence stratigraphic framework for the study area.The stratigraphic framework provides a reference for high-precision isochronous correlation of the Walloon coal measures in the Surat Basin.关键词
时序分析方法/高频层序地层格架/天文周期/Walloon煤系/苏拉特盆地Key words
time series analysis/high-frequency sequence stratigraphic framework/astronomical cycle/Walloon coal measures/Surat Basin分类
天文与地球科学引用本文复制引用
崔泽宏,敬宇鸿,黄文松,刘玲莉,张云飞..澳大利亚苏拉特盆地中—上侏罗统Walloon煤系旋回地层的天文周期驱动[J].高校地质学报,2024,30(6):737-746,10.基金项目
中国石油天然气股份有限公司重大科技专项课题"非常规油气技术可采资源差异化评价技术研究(2023ZZ0703)"资助 （2023ZZ0703）
