| 川东北普光地区下三叠统蒸发岩沉积特征与演化及其对钾盐矿形成的控制作用 |
| |
| 关键词:microfacies sequences stratigraphy sedimentary control on mineralization polyhalite Lower Triassic northeastern Sichuan Basin |
| 基金项目:国家重点研发计划项目“重点含盐盆地钾盐成矿规律、勘查技术与增储示范”所属课题“川东北海相新型杂卤石钾盐矿成矿规律、勘查技术与增储示范”(编号: 2023YFC2906503);中国地质调查局地质调查二级项目“四川盆地东北部锂钾资源综合调查评价”(编号: DD20190172);中国地质调查局地质调查三级项目“我国重要含盐盆地钾盐重点调查区区块优选与综合研究”(编号: DD20230296) |
|
| 摘要点击次数: 448 |
| 全文下载次数: 159 |
| 摘要: |
| Sedimentary Characteristics and Evolution of the Lower Triassic Evaporite and Its Control on the Formation of Potassium Ore in the Puguang Area, Northeastern Sichuan Basin |
| Thick layers of anhydrite and salt are deposited in the Middle and Lower Triassic strata in the Sichuan Basin. The rediscovery and transvaluation of polyhalite associated with salt, which has been called “a new type of polyhalite potassium ore”, has brought widespread attention to this mineral in recent years. However, research on this type of polyhalite has focused mainly on the aspects, such as the mineral development characteristics and genetic types, etc. Studies focusing on high-resolution analyses of the sedimentary characteristics and evolution of the surrounding strata and its control on the formation of polyhalite are rare. Therefore, in this study, microfacies and high-precision sequence stratigraphy analyses were carried out using core data of the continuous coring target interval of well CXD1. Fourteen microfacies types were identified and divided into six microfacies associations representing different sedimentary facies zones with different energy and environmental characteristics ranging from restricted to evaporative platform. On this basis, according to the vertical development of microfacies, stratigraphic thickness and typical diagnostic interfaces, four fourth-order sedimentary sequences and multiple fifth-order cycles within them were defined. The results implied that the primary polyhalite associated with salt in the northeast Sichuan Basin was obviously affected and controlled by sea level fluctuations. Specifically, it developed mainly in the superposition period between the end of regressions in the fourth-order sequences and transgressions of the fifth-order cycles. The evaporative condition in the former provided an important basis for the formation of polyhalite; however, the external seawater replenishment provided by the latter was the necessary condition. |
| ZUO Fanfan,ZHANG Yongsheng,SU Kui,GUI Baoling,XING Enyuan,NIU Xinsheng,PENG Yuan,SHANG Wenjun.2024.Sedimentary Characteristics and Evolution of the Lower Triassic Evaporite and Its Control on the Formation of Potassium Ore in the Puguang Area, Northeastern Sichuan Basin[J].Acta Geoscientica Sinica,45(5):651-664. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
|
|
|
|
|