The uplift and denudation history of the orogenic belt and the basin–mountain coupling process have directly or indirectly affected the generation, scale, and preservation of sandstone-type uranium deposits in the eastern Junggar Basin by controlling the uranium source, lithology, facies, hydrogeology, post-generation modification, and other mineralization conditions. Taking the eastern Junggar Basin as the research area, this study proposes the constraints on sandstone-type uranium deposits by the tectonic uplift and denudation history of the orogenic belt in the basin using the apatite fission track (AFT), detrital zircon geochronology, and other methods. The results of the AFT age test and thermal path simulation indicate that the orogenic belt in the eastern Junggar Basin underwent four rapid uplifts; (from approximately 300 Ma to approximately 250 Ma, from approximately 130 Ma to approximately 90 Ma, from approximately 65 Ma to approximately 30 Ma, and from approximately 20 Ma to 0 Ma). Moreover, the timing of the uplift has a spatial trend of gradually becoming younger from south to north. The detrital zircon U-Pb age test showed that the sediment source area of the basin is mainly distributed in three age intervals, i.e., 460–390, 360–270, and 190–170 Ma. The comprehensive evaluation of the clastic sediment composition, stratigraphic distribution of the erosion source area, and thermal history showed that a large amount of exposed Carboniferous–Permian granites in the Qinglidi and Karameri Mountain erosion source areas contributed dominant sediment material and uranium sources for the Triassic and Middle and Lower Jurassic strata in the basin. The Ordovician–Early Devonian granites only provided sediment sources for the Upper Triassic and Lower Jurassic strata in the basin. Altay Mountain contributed some sediment sources for the Middle and Upper Jurassic strata after the magmatic activity and rapid uplift occurred in the Middle Jurassic. Based on the comprehensive analysis of the influence of the tectonic uplift process of the orogenic belt and the transformation of material source areas on uranium mineralization, the granites in the erosion source areas are proposed to contribute both external and internal uranium sources for uranium mineralization. Uranium mineralization mainly occurred in the tectonic retreat period after the rapid uplifts of the Cretaceous and Paleogene. It was terminated by the intensive uplift-induced stratigraphic deformation in the Miocene.

The redeposition of pristine phosphorite plays an important role in phosphorus accumulation, which created reworked phosphorite extensively on the continental shelf. This paper, using geochemical analysis combined with data from petrology and diagenesis, focuses on the reconstruction of the formation processes of the Late Cretaceous Thaniyat phosphorite deposition in northwestern Saudi Arabia, which is a part of the famous large Neo-Tethys Ocean’s phosphorite deposit. The results of our study illustrate that the phosphorites represent the reworked products from the north, close to the edge of the Neo-Tethys Ocean’s shelf, where upwelling had accreted the pristine phosphorite. The reworked phosphatic grains were redeposited near the shore in sandstone, forming sandy phosphorite and on a carbonate platform and creating calcareous phosphorite. The microscale sedimentological and geochemical information hosted in the eroded phosphorite grains indicates that the source sediment, pristine phosphorite, occurred under a fluctuating geophysical condition and in a relatively limited geochemical environment. They were physically crushed and transported landward and deposited under oxic conditions, forming the Thaniyat phosphorites. Early diagenesis in the Thaniyat phosphorite was evidenced by recrystallization of the phosphate minerals, geochemical depletion, and C and O isotope excursion.

The Qianjiadian (QJD) uranium ore field, located in the southwest of the Songliao Basin of east China, was discovered within the red-variegated depositional layer of the Upper Cretaceous Yaojia Formation (Fm). It preformed some particular and complex characteristics in respect of the occurrence location, ore-hosting strata, alteration, and morphology of the ore body, compared with the sedimentary uranium deposit generated in the traditional dark coal-bearing clastic strata. In this study, the categories of organic matter (OM) within the Lower Member of Yaojia Fm (LYF), and their effects on the rock alteration and uranium mineralization process, were researched macro-microscopically. The aim of the study was to confirm the co-associated relationships between the gray layer, rock-faded zone, and tabular-shaped ore body, in addition to their genesis. Results showed that the OM mainly consists of synsedimentary carbonaceous detritus (kind-I), amorphous movable humic substances (kind-II), and deep-originated hydrocarbon fluid (kind-III), which widely led to rock-bleaching, green alteration, and different forms of pyritization and carbonation throughout the geological history. OMs of kind-I and kind-II were inherited from terrigenous higher plants, and did not directly adsorb and bio-reduce hexavalent uranyl ions during the metabolic processes of sulfate reducing bacteria (SRB), but indirectly promoted uranium precipitation related to a H₂S-rich secondary reducing barrier, produced by bacterial sulfate reduction (BSR) and the pyrolysis of the diabase dikes. III-OM was derived from deep reservoirs and exhibited multiple positive effects of increasing the reduction capacity of the primary weak reducing strata, and protecting and enriching the earlier ores. Uranium in the ores is mainly composed of pitchblende, followed by a small amount of coffinites and uranium-bearing titanium minerals. Combined with the geological setting of the QJD ore field, a six-stage ore-forming model for the LYF was constructed from the perspective of the reducing medium, i.e., (1) development of ore-bearing sand-bodies in the Yaojia Fm period; (2) formation of a tabular grey layer before the Nenjing Fm period; (3) initial bleaching and uranium pre-concentration during the diagenetic period; (4) initial mineralization and hydrocarbon reduction from the end of the Nenjing period to the end of the Mingshui period; (5) main mineralization and thermal transformation in the Paleogene period; and (6) superimposed mineralization in the Neogene period. The proposed new model does not enrich the uranium metallogenic mechanism for the red-variegated bed, but plays a key role in guiding the uranium prospecting for similar red beds, both in the Songliao Basin and in other sedimentary basins globally.