乌兹别克斯坦西部努库斯地区上白垩统土伦组沉积特征及铀成矿意义OA

In Nukus area of western Uzbekistan,the tectonic evolution has been stable since the Mesozoic-Cenozoic era and produced the Upper Cretaceous Toulon Formation,which is a set of thick-layered medium-fine-grained primary gray and grayish-green carbonaceous debris,with interlayer oxidation zones and certain exploration space for sandstone-type uranium deposits.To further enhance geological understanding and summarize and analyze the conditions for uranium mineralization,the article summarized and generated the characteristics of the sandstone clastic composition,sandstone structure,sedimentary structure,logging facies,and sand body distribution of the Toulon Formation.It holds that Upper Cretaceous Toulon Formation is a large delta sedimentary system developing from northeast to southwest,with thick-layer leading edge facies stable sand bodies.Uwais uplift was a small offshore uplift during the Toulon Formation sedimentation period,providing a small amount of nearby material sources.Through comprehensive analysis,it was believed that in Nukus area,the Lower Cambrian-Ordovician uranium-rich strata had not been exposed on the surface due to tectonic evolution,and the uranium source conditions were not favorable as those in the Central Kyzylkum uranium mineralization area.The post-sedimentary oxygenated water recharge direction in the study area was inconsistent with the paleocurrent direction during the sedimentary period and the main flow direction of the interlayer oxidation zone water was northwestward,therefore the favorable prospecting area should be the northwest part of Uwais uplift.