高校地质学报2024，Vol.30Issue(6)：726-736,11.DOI:10.16108/j.issn1006-7493.2023058
利用三角洲前积层的厚度恢复湖泊最大古水深:以渤海湾盆地秦南凹陷和珠江口盆地惠州凹陷为例
Using the Thickness of Delta Foredeposits to Restore the Maximum Paleo-water Depth of Lakes:A Case Study of Qinnan Sag in Bohai Bay Basin and Huizhou Sag in Pearl River Mouth Basin
摘要
Abstract
Water depth plays a decisive role in the redox conditions of a basin and plays an important role in the enrichment and preservation of organic matter in sedimentary basins.Previous studies mainly relied on paleontology,element geochemistry,stratigraphic thickness,and other methods for qualitative and semi-quantitative palaeodepth restoration.However,these methods have a high dependence on original samples and low prediction accuracy and are not suitable for Palaeogene Lake basin palaeodepth restoration in offshore basins.In this study,the depth of paleowater is mainly restored based on the thickness of the delta for deposits in seismic profiles.By using this method,the maximum palaeobathymetric during the sedimentary period of the third Member of the Shahejie Formation of the Eocene in Qinnan west subsag of Bohai Bay Basin is 595 m,and the maximum paleowater depth during the sedimentary period of Wenchang Formation in the southwest of Huizhou Sag of Pearl River Mouth Basin is 526 m.Combined with previous research results,it is found that the rate of sag-controlling fault activity is strong in the third Member of the Shahejie Formation period of Qinnan Sag and the Wenchang Formation period of Huizhou Sag,and they are during the strong rifting of the basin,which controls the formation of deep water lake basins.During this period,many Sags in Bohai Bay Basin and Pearl River Mouth Basin are in deep-water-ultra-deepwater environments,so it is inferred that the deep water environment is the result of strong fault activity.Then the redox conditions of the lake basin are controlled,and more organic matter is preserved in the lake basin to form high-quality source rocks.关键词
古水深/三角洲前积层/秦南凹陷/惠州凹陷/始新世Key words
palaeobathymetric/delta foredeposit/Qinnan Sag/Huizhou Sag/Eocene分类
天文与地球科学引用本文复制引用
党昭卿,陈莹,吕成福,白志钊,肖月也,周钱山..利用三角洲前积层的厚度恢复湖泊最大古水深:以渤海湾盆地秦南凹陷和珠江口盆地惠州凹陷为例[J].高校地质学报,2024,30(6):726-736,11.基金项目
国家自然科学基金面上项目(41972155) （41972155）
中海油项目"中国近海盆地潜在富油凹陷资源潜力、成藏机构与突破方向"(编号:YXKY-ZX01-2021)联合资助 （编号:YXKY-ZX01-2021）
