Reservoir Prediction And Analysis Of Sandstone-type Uranium Deposits In Southwestern Ordos Basin

In recent years,many large-scale uranium-grade sandstone-type uranium deposits have been found in many areas,such as the eastern,northern,and central regions of the Ordos Basin.Gamma logging in the area found that a large number of radioactive anomalies appeared in the early exploration in the Xichuan-Zhenyuan area at the edge of the southwestern basin of Ordos.Through the combination of seismic and logging data,the area is suspected to have a large scale.Sandstone-type uranium deposits have been formed,so since 2017,the drilling of three uranium mines in the area after preliminary geological and geophysical logging work has shown that the area has the potential to form higher-grade sandstone-type uranium deposits.,In line with the "oil and uranium simultaneous exploration" prospecting theory of oil and uranium inside the basin.Existing drilling data show that the sandstone-type uranium deposits in the study area are roughly distributed in the formations of the Luohe Formation of Zhidan Group in the Early Cretaceous,with a buried depth of about 1,000 meters,a shallow depth,and a relatively wide area,Has the potential to form large-scale sandstone-type uranium deposits.The purpose of this article is to understand the geological structure of the study area,the distribution of the sedimentary special stratum,and the relationship of the study area through the study of the theory of hydrouranium ore,structural geology,sedimentary geology,uranium ore geology,geophysics,and so on.The basic five elements of geophysics,etc.,through seismic exploration technology analysis,analyze the seismic attributes of the target layer,understand the seismic response characteristics of sandstone-type uranium deposits,and preliminary understand the underground structure characteristics of the study area and the distribution of sedimentary strata through the seismic section.For the relevant tectonic conditions of sandstone-type uranium deposits and the reservoir strata that are favorable for the storage of sandstone-type uranium deposits,the seismic profile in the study area shows a large range of near-horizontal continuums that are continuous on the same axis,which is stable with the Ordos Basin."Tong Basin" features are consistent.The inversion profile shows a large set of formations with continuum continuum and distinct energy strength,as well as obvious faults and slight fold tectonic changes.These are all represented by the formation environment and reservoir changes of sandstone-type uranium deposits in this area feature.By analyzing the log data in the study area,it is found that the gamma logging anomalies in the formations at a depth of about 1,000 meters are very prominent,which is significantly different from the gamma value of uranium-free formations,and is consistent with the uranium-containing uranium deposits or uranium mineralization characteristics.Low density anomaly and high sonic time difference anomaly in the formation corresponding to the density log and sonic time difference log,to determine that the porosity of the formation is higher than that of the upper and lower surrounding rock formations.According to the sedimentary characteristics and physical properties of the formation The change judges that the formation is very favorable for the enrichment of sandstone-type uranium deposits.Through the analysis of logging data,fine division of the target layer,accurate horizon calibration of seismic synthesis records,broadband constrained inversion,and related parameter inversion,such as comprehensive logistic research,the uraniumcontaining uranium of the sandstone-type uranium deposit in the study area was completed.Reservoir prediction has obtained the spatial distribution of sandstone-type uranium deposits in the study area.