The Jin72 well block in Hangjinqi, located in the northern Ordos Basin, has been identified as a potential area for natural gas development. However, the geological characteristics of the main target layer, the He1 Member of Lower Shihezi Formation, should be probed into for further study. In order to gain better understanding of the stratigraphic and sedimentary characteristics of this area and to delineate sedimentary micro-facies boundary of sublayer units, comprehensive analysis was conducted using core, well logging, and seismic data. The target strata core was observed to identify various lithological interfaces, and the logging curves were calibrated in detail using the core marker layer interface and the high-frequency stratigraphic sequence interface. The logging response characteristics of all interfaces were then summarized. Additionally, a detailed subdivision of the strata from the Taiyuan Formation to the Lower Shihezi Formation was achieved through a combination of well and seismic data. Based on observations of lithofacies and analysis of depositional environment, the logging curve characteristics of the lithofacies were summarized to complete the sedimentary micro-facies division of individual wells. The seismic facies were calibrated using individual well sedimentary micro-facies, and a comprehensive seismic response model of the sedimentary micro-facies was established. The reflection characteristics derived from the well-seismic calibration of the target layer and combined with geophysical forward modeling indicated that the most suitable attribute for reflecting the sedimentary micro-facies was determined to be the maximum trough amplitude, which was extracted using geophysical stratigraphic slicing technology. Through well-seismic combination and mutual calibration techniques, the sedimentary micro-facies planar distribution of the H1-1 sublayer was comprehensively mapped. The results showed that the He1 Member in study area could be further divided into four sublayers and seven five-level high-frequency sequences. The combination of lithofacies markers, facies sequence characteristics, and the vertical and horizontal distribution of sandstone bodies allowed the conclusion that the sedimentary type was determined to be braided river deposits, with channel bar, channel filling, and floodplain being the three most dominant sedimentary micro-facies. The sedimentary micro-facies distribution of the H1-1 sublayer revealed the development of 4–6 braided river channels with widths ranging from 1.5 to 6.5 km and a nearly north–south distribution. The use of well-seismic combination, in combination with step-by-step constraints, allows for the full exploitation of the high lateral resolution of seismic data, providing an effective means of achieving sublayer correlation and boundary delineation of sedimentary micro-facies. These research results can serve as constraint boundaries for further evaluation and zone selection of sublayer units.