Wafangdian, China, is widely known for its rich primary kimberlite diamond. Kimberlite pipes (veins) are well-developed in Wafangdian, but only exist in shallow areas. The reason for the pinching out or disappearance remains unclear. Some studies have suggested that a possible reason is the thrust fault at the pipe bottom, but no substantial evidence of such geological movement exists. In this study, structural analysis and drilling were integrated based on a detailed field geological survey. We found a new thrust-nappe structure in the Wafangdian diamond metallogenic belt, which comprised a hanging wall allochthonous terrane, footwall autochthon, and thrust fault belt. Statistics of the striation lineation and fold hinge showed that the main direction of thrust nappe is SEE–NWW with a low angle. The calculated horizontal displacement of the major thrust nappe was approximately 3.2 km, and the movement distance of the secondary thrust fault at the bottom of Pipe No. 50 was approximately 1.5 ± 0.5 km. The formation age of the thrust-nappe structure might be the middle to late Jurassic, and the driving force was mainly related to the subduction of the Paleo-Pacific Plate. The discovery of the thrust-nappe structure provides a direction and scientific basis for deep diamond prospecting in Wafangdian, and the SEE areas of Pipe No. 50 and surrounding mines are potential focus areas for future deep exploration. Additionally, a 10-m thick diamond-containing kimberlite was obtained by drilling, providing a leap from theory to practice and serving as a case of deep structural analysis prospecting.

Beach bars are important reservoirs and have good exploration potential in several petroliferous basins globally. However, the current models used for understanding the architecture of beach bars are an impediment to progress in this area. Our study area was the Binhai Park of Rongcheng, Moon Bay, and the Fenghe Estuary of Qingdao, along the coast of Shandong Peninsula, because they are ideal sites to study modern sedimentation; we also analyzed the beach bar of the fourth member of the Shahejie Formation of the Paleogene deposits found in Dongying Sag (Bohai Bay basin), which is an ideal region to study paleosedimentation. We used outcrops, fine-scale scanning with unmanned aerial vehicles (UAVs), cores, and conventional and image logging to study these regions hydrodynamic zoning and sedimentary environment and establish fine-scale architectural units. Automatic identification of beach bar architectural units was also conducted through principal component analysis and Bayesian discrimination. The results indicated that the beach bars could be divided into shore beach, submerged shoal, and bar, based on different sedimentary characteristics. The architectural units of the beach bars were divided into five different types, based on the hydrodynamic characteristics and sedimentary environment, corresponding to four evolutionary stages. Additionally, a discrimination standard was established, based on principal component analysis and Bayesian discrimination, while using fine-scale recognition for the verification of the units. The coincidence between manual recognition and machine recognition results could be 94.8%. The discrepancy of the evolutionary stages of the beach bars was compared based on the characteristics of architectural units, and the different sedimentary models for shore beach, submerged shoal, and bar were established eventually. We hope that our methodology and models can address the limitations in the studies conducted on beach-bar reservoirs, while promoting improvements in the related theories and optimizing the exploration and development of beach-bar reservoirs.