A method of generating a noise estimate during seismic surveying, including measuring noise energy having a plurality of frequencies in a second time interval. The second time interval having a second start time delayed from a first start time of a first time interval during which a first plurality of reflected seismic signals are present. The plurality of reflected seismic signals having the plurality of frequencies. The second time interval approximately concurrent with the first time interval to measure one of the plurality of frequencies of the noise energy different than one of the plurality of frequencies of the first plurality of reflected seismic signals that are present. A noise estimate is generated based on the noise energy measured.