Translations:Dictionary:Array (seismic)/3/en

2. The arrangement or pattern of a group of geophones or sources (Figure A-20). Arrays discriminate against events on the basis of their moveout or apparent wavelength; see directivity graph. For a uniform array (see Figure D-15) of n geophones separated by the distance d, the effective array length is nd and the first null response occurs when the apparent wavelength equals this. The half-width of the main lobe at 0.7 peak amplitude defines the pass wavelength. For a nonuniform array, the effective array length is the length of the uniform array that has the same pass wavelength. Compare spread.