海洋地质前沿2025，Vol.41Issue(12)：29-41,13.DOI:10.16028/j.1009-2722.2025.006
西江凹陷韩江组天文年代标尺建立及高频层序划分
Establishment of astronomical time scale and high-frequency sequence stratigraphy of the Hanjiang Formation in the Xijiang Sag
摘要
Abstract
This study employs cyclostratigraphic methods to investigate the Hanjiang Formation in the Xijiang Sag of the Pearl River Mouth Basin.Using natural gamma-ray logging data as the paleoclimate proxy and integ-rating time series analysis techniques,we identified astronomical orbital signals and extract the 405 ka long ec-centricity cycle using Gaussian bandpass filtering to construct a high-precision astronomical time scale.We ap-plied the sedimentary noise models(DYNOT and ρ1 models),reconstructed relative sea-level changes,and com-bined lithological and logging curve characteristics,based on which high-frequency sequence stratigraphic divi-sion of the Hanjiang Formation was conducted.Results demonstrate that the Hanjiang Formation was controlled by astronomical orbital cycles,with a depositional duration of 6.08 Ma and an optimal sedimentation rate of 20 cm/ka.Through astronomical tuning,a high-resolution astronomical time scale spanning from 16.17 Ma to 10.09 Ma was established,dividing the formation into 15 fourth-order sequences and 64 fifth-order sequences.This study highlights the critical role of sea-level fluctuations and sedimentation rates in the development of sand bodies during the Middle Miocene.This research not only provided a methodological support for understanding the sedimentary facies differentiation,sequence stacking patterns,and reservoir development of the Hanjiang Formation,but also confirmed the significance of Milankovitch cycles in high-resolution stratigraphic studies,of-fering new scientific insights and technical approaches for reservoir prediction and evaluation in the hydrocarbon exploration of the Pearl River Mouth Basin.关键词
旋回地层学/韩江组/天文年代标尺/海平面变化/沉积速率/高频层序Key words
cyclostratigraphy/Hanjiang Formation/astronomical time scale/sea-level change/sedimentation rate/high-frequency sequence stratigraphy分类
海洋科学引用本文复制引用
梁玉冰,张尚锋,徐恩泽,王雅宁,朱锐,梁建昊,巩高阳,韩睿..西江凹陷韩江组天文年代标尺建立及高频层序划分[J].海洋地质前沿,2025,41(12):29-41,13.基金项目
国家自然科学基金"南海北部宽缓大陆架海平面变化及双坡折带层序地层模型"(41472098) （41472098）
