Inferring Ocean Currents from the Shapes of Towed Seismic Streamers

The vertical shape of a buoyant acoustic streamer between depth control units

“…When DCUs are included in the model, even though they provide a significant local force bending stiffness can still be safely neglected (Grant et al, 2014). Fixing θ 3 0, to remove any torsional effects, and setting DðsÞ ¼ d now lead to the reduced problem…”

Inferences of ocean currents from seismic streamer position data

“…Additionally, inferring the currents at a length scale that is shorter than the length of the streamers will provide valuable information on ocean currents to the oceanographic community. At present, currents on this length scale are poorly observed, being at a smaller scale than is presently observed using satellite altimetry; it is thought that processes on this smaller scale may play an important role in energy dissipation in the ocean and mixing of gases and nutrients (Grant, Laws and Shuckburgh ).…”

“…Grant et al . () recognised that, in many commercial streamer systems, there are no tension measurements along the length of the streamers; instead there is typically a single measurement of the tension at the head of the streamer. The lack of tension measurements makes the inverse problem for the currents fundamentally underdetermined.…”

“…The aim of this paper is to extend the work of Grant et al . () by attempting to apply the idea to a real dataset and thus demonstrate that inferring currents is possible. This is the first attempt (to the author's knowledge) to infer the ocean currents from real streamer shape data.…”

“…Grant et al . () assumed that the velocity of the streamer and its local angle were the observed variables. In truth, the only available data are the tension at the head of each streamer; the currents recorded at the vessel by the acoustic Doppler current profiler; the positions along the streamer, determined by an acoustic network at each shotpoint; and the time of each shotpoint.…”