The positioning of ocean bottom seismometers (OBS) is a key step in the processing flow of OBS data,particularly in the case of self popup types of OBS instruments. The exhaust of first arrivals from airgun shots, rather than relying on the acoustic transponders mounted in the OBS, and is becoming a trend and generally leads to more accurate positioning due to the statistics from a large number of shots. In this paper,a linearization of the OBS positioning problem via the multilateration technique is discussed. The discussed linear solution solves jointly for the average water layer velocity and the OBS position using only shot locations and first arrival times as input data.
Source: usgs.gov