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Diffusion models are increasingly applied in low‐light image enhancement tasks due to their exceptional capability to model data distributions, but most current methods focus only on the original pixel space and neglect the potential of Fourier frequency information. In this article, SFDiff is proposed, a novel low‐light image enhancement method that integrates Fourier frequency information into the diffusion process. Specifically, Fourier transforms are applied at both the image and feature levels to separately enhance the amplitude and phase components, which restores global illumination degradation and positional information. Then a Spatial‐Frequency Fusion (SFF) block is used to fully integrate and interact with the information across spatial and frequency domains. Since illumination degradation is primarily manifested in the amplitude component, a loss function based on maximum likelihood learning is employed to constrain the amplitude component at each step of the sampling process, ensuring that the reverse process maintains an optimal trajectory. Owing to the streamlined network design and the fact that the Fourier transform requires no extra parameters, SFDiff achieves a reduction in parameters of over 35%$35\%$ compared to several state‐of‐the‐art (SOTA) diffusion models and delivers high‐quality enhancement results on multiple real‐world datasets. The code is available at https://github.com/MrWan001/SFDiff. [ABSTRACT FROM AUTHOR]

The Chang 9 interval at the lower part of the Upper Triassic Yanchang Formation in the Ordos Basin is a new discovery sequence for strategy replacement in the oil exploration field. By conducting a comprehensive study of outcrop sections, well drilling, drill cores, well loggings, and test data, based on the relevant research achievements of some predecessors, and combined with the analysis of geological background of this basin, it is considered that the Ordos Basin is a broad and shallow lake basin with terrigenous clastic deposition during Late Triassic Chang 9 time. The lake basin had been supplied with multiple drainage systems and provenances. The lake water in this basin is inland freshwater to brackish water. Sedimentary framework is characterized by the development of 'a lake surrounded by multiple deltas' pattern. On the basis of paleocurrent analysis, distribution of sedimentary facies and sand bodies, and the quantitative analysis results of rock fragment components and trace elements of Chang 9 sandstone, it is recognized comprehensively that the Chang 9 provenances have a close connection with the basin tectonic evolution and paleogeographic background. The provenance of the Ordos Basin in Chang 9 time can be divided into five provenance systems: i.e., the northeast, north, northwest, southwest, and south provenance systems. Characteristics of rock fragment and trace element assemblages are documented in the individual provenance systems, respectively. It is inferred that terrigenous clastic sediments in Chang 9 interval mainly originate from the old lands around the basin. Parent rocks in these provenances are composed of a variety of rocks dominated by metamorphic rocks. [ABSTRACT FROM AUTHOR]

LA-ICP-MS U-Pb dating has been performed on detrital zircons from the Nanyinger Group in the eastern section of the north Qilian orogenic belt in Jingyuan County, Gansu Province. The results show five major age groups: 3.1-2.0, 1.8-1.4, 1.4-0.8, 0.6-0.4, and ~0.26 Ga. Archean to Neoproterozoic zircons were derived from the central Qilian belt. The early Paleozoic grains are considered to have been derived from the magmatic arc related to ocean closure. The youngest age may be derived from the recycling of sediments prior to the Nanyinger Group. The youngest detrital zircon age (262 ± 5 Ma) is close to the depositional age of the strata, suggesting rapid uplift of the Qilian Mountains. In the early Indosinian, the palaeo-Qilian Mountains uplifted rapidly and provided the main source for the Hexi Corridor basins. The North Qilian Belt is the southern boundary of the Hexi Corridor basins. From the Ordovician to the Triassic, the depocenter gradually moved to the Qilian Mountains and was very close to the Qilian Mountains in the Late Triassic. By comparing with previous research, we infer that the Hexi Corridor basin may not connect with the Ordos Basin in the Triassic. [ABSTRACT FROM AUTHOR]