Abstract:
Oilfield geological surveys and drilling data reveal distinct uranium anomalies in the GQ region of the northern Songliao Basin, specifically at the southern end of the Daqing Placanticline. Some drillings indicate that uranium mineralization has reached industrial grades, indicating significant potential for uranium metallogenesis in this area. However, the distribution characteristics of the main ore-bearing layer, the Sifangtai Formation sandstone, remain unclear, impeding further exploration breakthroughs in the region. Identifying the 3D geological structure and the developmental characteristics of ore-bearing sandstone bodies in the basin is crucial for mineralization predictions. Therefore, we conducted high-precision 3D reflection seismic exploration in the area and acquired a 50km
2 3D seismic data volume in the GQ region. Through detailed data processing, well logging curve reconstruction, and combined horizontal slicing, we revealed the thickness and planar distribution characteristics of sand layers in the upper, middle, and lower sections of the Sifangtai Formation. This led to the interpretation of the "mud sand mud" stratigraphic structure, structure, lithology, and rock equivalence closely related to sandstone-type uranium deposits. The study found that the Sifangtai Formation has a higher burial depth in the south and lower depth in the north, with thinner thicknesses in the south and thicker in the north. The sand body at the bottom of the lower section of the Sifangtai Formation is thick and stable, with good connectivity. It forms a stable "mud sand mud" stratigraphic structure with fine clastic sediments from the middle section of the Sifangtai Formation and the fifth section of the Nenjiang Formation, which is conducive to mineralization. A comprehensive analysis of sandstone-type uranium metallogenic factors suggests that areas with sand body thicknesses exceeding 20m are favorable for mineralization. Consequently, six uranium exploration target areas have been delineated, with five inferred to be confirmed by later drilling.