The 3D marine seismic technology is the key technology for the deep-water hydrocarbon exploration and development. Compared with conventional 3D towed streamer seismic, which lacks low frequency components, the 3D slant streamer seismic contains abundant low and high frequency components, which can effectively improve the imaging accuracy of deep water turbidite sand. Ghost in slant broadband seismic data are one of the key factors affecting high-resolution imaging of deep-water turbidite sandstones, and In this paper, On the basis of analyzing the ghost notch diversity of 3D slant streamer seismic, we have established a method for generating 3D oblique streamer seismic mirror data, systematically investigated the principle of deghosting by joint deconvolution of a migration and a mirror migration, and optimized the pre-stacked deghosting by multichannel joint deconvolution with the schmidt orthogonal polynomial technique. The pre-stack or post-stack deghosting by joint deconvolution can effectively suppress the slant streamer ghost and improve the resolution of seismic imaging. The slant streamer broadband seismic has achieved good results in deepwater DX reservoir exploration. The slant broadband seismic imaging is the doubled resolution compared with that of conventional marine 3D seismic imaging, and can improves the seismic identification accuracy of turbidite. It can not only identify turbidite sandstone with a thickness of about 8 meters, but also finely characterize the internal characteristics of turbidite sand in deepwater reservoirs. Reservoir characterization based on the slant broadband seismic data improves the accuracy of reservoir geological reserve assessment and reduces the risk of deepwater hydrocarbon exploration and developmen.