Broadband seismic data is data that is rich in both low and high frequencies. High frequencies increase temporal resolution, and low frequencies reduce the side lobes of the wavelet. Bandwidth, a measure of broadband data, is defined as the difference between the upper and lower frequencies in a continuous set of frequencies. It is often defined in octaves: two frequencies are one octave apart if they have a ratio of two. A standard goal in broadband processing is to achieve six octaves of bandwidth of seismic data: interference between the source pulse and reflections from the water surface - "ghosts" - and the "earth filter," which attenuates high  frequencies in the wavefield as it travels through the subsurface.