The application on the towed-type shallow high-accuracy seismic detection for coastal tidal flats

Abstract

Restricted by the geological exploration equipment and tidal time, the deep seismic detection technology with large offset for exploration of oil and gas resources is often used in the seismic survey of the coastal tidal flats. Furthermore, the coastal tidal flats are only treated as the transition belt of the paralic zone, resulting in the low degree of geological exploration and low detection accuracy, which cannot meet the requirement for high-accuracy exploration in the coastal tidal flats. Conventional shallow seismic exploration technology can detect effectively the bottom interface and internal horizon of the shallow Quaternary system in the coastal tidal flats, but the equipment for data acquisition is complex, and the acquisition efficiency is low, restricting directly the seismic exploration in the coastal tidal flats. Therefore, a shallow high-accuracy seismic detection technology has been developed in this study, which is suitable for the coastal tidal flats. By making full use of the characteristics of the flat terrain in the coastal tidal flats, the method for towed data acquisition has been used, and the seismic detection equipment has been simplified in the tidal flats. With this method, the exploration cost has been reduced, and the data acquisition efficiency has been improved. The detection accuracy can reach the level of meters, and the detection depth is more than 800m with this method. With this technology, the shallow stratigraphic structure and interface in the coastal tidal flats can be detected effectively, and the location of paleochannels, concealed faults and shallow gas can be determined, which support effectively the geological survey of the coastal zone and offshore engineering, being of great practical significance for scientific disaster prevention and mitigation.