Abstract: A method for determining the absolute geophysical location of a streamer using reference signal source(s), or alternately detector(s), of unknown location. The absolute geophysical location of a seismic streamer is determined by the optimal sequential use of the field measurements of reference signal travel time, streamer magnetic heading and conventional navigational measurement. The absolute location determination is accomplished in three steps. Each step solves for one aspect of streamer location by optimally utilizing one of three types of field measurement. This procedure requires no a priori knowledge of the absolute location of the reference signal source(s), or alternately detector(s).

Abstract: A marine seismic survey is disclosed in which a plurality of steerage centers are selected for circular traversal thereabout by a marine vessel towing a streamer cable. While the vessel and the streamer are following a circular track about a steerage center, the feathering of the cable creates a separate concentric track line for each of the mid-points between the receivers included in the cable and the source. In this manner an areal coverage is assured which requires no reliance on unpredictable and uncontrollable currents for the desired feathering. An additional important feature of the current disclosure is that there is little wasted time in which the survey vessel moves outside of the overall surveyed area. A preferred course tracking for the vessel is to move from the arc of one steerage course line to another in tangential fashion.

Abstract: A novel array of vertically and horizontally spaced hydrophones is shown which is capable of high ratio of desired signal to noise because of good directional sensitivity when used with any seismic source. Alternatively, a novel directionally sensitive array of vertically and horizontally spaced seismic sources is disclosed for use in seismic surveying with any spread of hydrophones or geophones, again attaining a high ratio of desired signal to noise. A reception pattern (in the first case) and a radiation pattern (in the second place) is produced which essentially eliminates reception or radiation at all frequencies except for waves within a predetermined angle with respect to the array. The sensitivity is essentially constant within such angle for all frequencies and essentially zero outside it.