Geophysical techniques have been traditionally used, not only in the oil and gas industry, but also in other areas, as for engineering and oceanography studies. For these, one of the widely used methods is the high resolution reflection seismic, which consists in the investigation of structures and layers in shallow depths bellow the seafloor. In most cases, the data associated to this method do not allow any treatment, and are interpreted in its raw form. However, some studies have proved that the processing of this kind of data can consistently improve data quality and make the interpretation even better, especially in noisy data. This paper describes the processing of high-resolution single-channel seismic lines acquired with a sub-bottom profiler system, analyzing the results and proving that seismic processing techniques can improve the interpretation of shallow seismic data. For this purpose, some conventional seismic processing techniques such as frequency filtering, amplitude correction and migration were applied to the data. The seismic lines used in this project are located near the Cabo Frio Island, SE coast of Brazil, where a feature with difficult characterization and showing an ambiguous interpretation can be observed. Analyzing the raw data, there are evidences to associate this structure either to a beachrock or to an outcrop of the crystalline basement. After submitting the seismic lines to a processing flow, the improvement in the data quality is clearly visible and the characterization of the geological feature could be done more appropriately as a beachrock. By comparing the changes observed in the post-processed data with the raw data, it was noted that the adapting conventional processing techniques can refine the seismic image, improving the interpretation of shallow seismic data. New tests are being conducted in order to establish a basic processing flow for a single-channel high-resolution seismic data with applications on several problems where the definition of small geological features is necessary.