Abstract: The Dongfang 1−1 diapir area in the Yinggehai Basin has superior conditions for hydrocarbon accumulation. Several shallow gas fields have been proven in this area using high-resolution towed streamer seismic data. However, the widespread seismic fuzzy zones in the medium–deep layers exhibit low imaging resolution, which cannot be addressed even through rounds of reprocessing, thus seriously restricting the hydrocarbon exploration process in the central depression zone. After identifying the genetic mechanisms of the fuzzy zones, this paper proposes a set of seismic acquisition and P-wave processing technology system based on ocean bottom node (OBN), and innovatively designs an "three highs and one low" (high signal-to-noise ratio, high fold, high quality, and low cost) OBN geometry-variable acquisition scheme to break through the interferences of shallow gas shielding and diapiric fractures. Moreover, the key technologies such as dual-sensor summation in the wavelet domain, full-waveform inversion (FWI) in viscoelastic media and Kirchhoff prestack depth Q-migration are combined to significantly improve the accuracy of OBN P-wave imaging. Applications show that the newly acquired seismic data are significantly improved in the signal-to-noise ratio (SNR) compared with the old data, thus enabling more accurate and reliable velocity modeling. The proposed technology system allows for the first realization of clear imaging of diapir cores in greatly reduced fuzzy areas, providing high-quality data for the hydrocarbon exploration in the medium–deep layers of the Dongfang 1−1 diapir area.