沙特赛尼亚特含铀磷块岩矿床区域地质背景及对磷-铀的制约作用  

Regional Geological Background and Its Constraints on Phosphorusuranium Interaction of the Thaniyat Uranium Bearing Phosphorite Deposit in Saudi Arabia

作　　者：李治兴[1] 秦明宽[1] 范洪海 蔡煜琦[1] 衣龙升[1] 张云龙 李国臣[1] 张康[1] 郭帮杰[2] LI Zhixing;QIN Mingkuan;FAN Honghai;CAI Yuqi;YI Longsheng;ZHANG Yunlong;LI Guochen;ZHANG Kang;GUO Bangjie(CNNC Key Laboratory of Uranium Resources Exploration and Evaluation Technology,Beijing Research Institute of Uranium Geology,Beijing 100029,China;National Key Laboratory of Remote Sensing Information and Image Analysis Technology,BeijingResearch Institute of Uranium Geology,Beijing 100029,China)

机构地区：[1]核工业北京地质研究院中核集团铀资源勘查与评价技术重点实验室,北京100029 [2]核工业北京地质研究院遥感信息与图像分析技术国家级重点实验室,北京100029

出　　处：《世界核地质科学》2022年第4期685-697,共13页World Nuclear Geoscience

基　　金：沙特阿拉伯磷块岩型铀钍资源调查评价(编号:地技ST1703);中国铀成矿区划及找矿部署研究(编号:202143-5);红杂色砂岩后生蚀变机理成矿模拟实验(编号:202246-6)联合资助。

摘　　要：赛尼亚特含铀磷块岩矿床所在的新特提斯磷块岩成矿域占全球磷矿石的陆上储量约82.7%,该成矿域磷块岩如此大规模聚集的成矿地质背景研究程度较弱。文章通过系统梳理全球磷块岩成矿域、成磷时间,解剖赛尼亚特含铀磷块岩矿床区域古地理环境、沉积构造演化和地质特征,结果表明,全球磷块岩分布主要为5大成矿域,形成重要工业磷矿床主要有8大成磷期,其中晚震旦世—早寒武世、二叠纪、晚白垩世—古近纪为全球3大重要成磷期。赛尼亚特含铀磷块岩矿床位于新特提斯磷块岩成矿域东地中海成矿省锡尔汉—图赖夫盆地西南部,是晚白垩世—古近纪成磷事件的一部分。在整个古生代,阿拉伯半岛的大部分为古特提斯洋边缘的一部分,广泛沉积了硅质碎屑岩,在白垩纪早期(至阿尔布期早期),东地中海地区几乎完全露出地面,沉积作用以河流碎屑沉积为主,晚白垩世土仑期至始新世,非洲-阿拉伯板块的海洋前缘与欧亚板块俯冲海沟碰撞,新特提斯洋发生闭合这一事件从时空和成因上控制了含铀磷块岩矿床的形成。晚白垩世Zaluma期,新特提斯洋开始海侵,在图赖夫期处于海侵阶段,直到古新世结束,在沙特北部从底到顶分别形成了Jalamid组,Mira组和Umm Wu’al组。他们逐渐向盆地中心方向退缩的分布特征表示形成的海侵规模逐渐减弱。赛尼亚特地区特殊的古地理环境和区域沉积构造演化是含铀磷块岩大规模聚集的主因,海侵事件是赛尼亚特地区含铀磷块岩沉积的诱因。The phorsphorite reserves of Thaniyat area in Saudi Arabia of Neo-Tethys phosphorite metallogenic domain take about 82.7% the world ’s land reserves of phosphate rock. However,study on the metallogenic geological background for such large-scale accumulation of phosphate rock is quite weak. This paper summarized the global phosphorite metallogenic domain and phosphorite forming time were systematically analyzed, and the paleogeographic environment,regional sedimentary-tectonic evolution and geological characteristics of the Thaniyat area in northern Saudi Arabia. The results showed that the phosphorites were distributed in five major metallogenic domains, and the global important industrial phosphorite deposits were formed mainly in eight phosphogenic periods, and the most important three are the Late Sinian-Early Cambrian,Permian and Late Cretaceous-Paleogene. Thaniyat area is located in the southwest of SirhanTurayf basin, the eastern Mediterranean metallogenic province of Neo-Tethys phosphorite metallogenic domain and composed part of the major Late Cretaceous-Palaeogene phosphorus events. During the Paleozoic, much of the Arabian Peninsula was part of the Paleo-Tethys margin,where extensive sequences of siliceous clastic rock were deposited, virtually no phosphorites, but only thin-bedded carbonates. During the Early Cretaceous(to Early Albian), the eastern Mediterranean was almost completely exposed and the sedimentation was dominated by fluvial clastic deposits. From the Late Cretaceous Turonian to Eocene, after the oceanic front of the AfroArabian plate collided with the subduction trench of the Eurasian plate, the Neo-Tethys Ocean closed, which controlled the formation of phosphorite deposits in time, space and genesis. The NeoTethys began its transgression during the Late Cretaceous Zaluma Stage, and was in the transgressive stage during the Turayf Stage until the end of the Paleocene. The Jalamid Formation,the Mira Formation and the Umm Wu’al Formation were formed from bottom to top in northern Saudi

关 键 词：时空分布 区域沉积-构造演化 区域地质特征 赛尼亚特含铀磷块岩矿床 

分 类 号：P619.14[天文地球—矿床学]