Marine seismic data are always affected by noise. An effective method to handle a broad range of noise problems is a time-frequency de-noising algorithm. In this paper we explain details regarding the implementation of such a method. Special emphasis is given to the choice of threshold values, where several different strategies are investigated. In addition we present a number of processing results where time-frequency de-noising has been successfully applied to attenuate noise resulting from swell, cavitation, strumming and seismic interference. Our seismic interference noise removal approach applies time-frequency de-noising on slowness gathers (t — p domain). This processing trick represents a novel approach, which efficiently handles certain types of seismic interference noise that otherwise are difficult to attenuate. We show that time-frequency de-noising is an effective, amplitude preserving and robust tool that gives superior results compared to many other conventional de-noising algorithms (for example frequency filtering, x — p or fx-prediction). As a background, some of the physical mechanisms responsible for the different types of noise are also explained. Such physical understanding is important because it can provide guidelines for future survey planning and for the actual processing.
展开▼
