Techniques are disclosed relating to reducing noise in geophysical marine survey data through use of a dip map data structure. Such techniques may include adapting a model of multiple noise to seismic data. A multiple dip map may be generated by convolving the adapted model of multiple noise with a set of directional filters. A modified record of the seismic data may be generated through adaptive subtraction that is sufficient to remove most multiple events but may also damage at least some primary events. A primary dip map may then be determined from the modified record by interpolation dependent on the multiple dip map. A noise template may then be adaptively subtracted from the seismic data. Prior to the adaptive subtraction, the noise template is adapted to the seismic data by a degree of adaptation that is determined dependent upon relative amplitudes of the primary and multiple dip maps.