To change the relative contribution of components of a stack with record time. 1. In the early part of the record, long-offset traces may be muted (excluded from the stack) because they are dominated by refraction arrivals or because their frequency content after NMO correction is appreciably lower than other traces. Muting may be either abrupt or gradual, and may distort the design for deconvolution or other operators. Muting is shown in Figure V-7. 2. Muting may be done over certain time intervals to keep ground roll, air waves, or noise bursts out of the stack. See also tail mute (inside mute) and surgical mute, and compare diversity stack. Also called fade.