Precision measurement of ocean depth

Abstract

An instrument for recording ocean depth to an accuracy better than one fathom in 3,000 fathoms has been constructed and tested at sea. The instrumentation includes the electronic portion of any of the standard deep sea echo sounders, a modified facsimile receiver, an additional open scale recorder, and appropriate gating, switching, filtering, and monitoring equipment for connecting them. Data from over 1,300 miles of track has been obtained from the following general topographic provinces of the North Atlantic: the Continental Rise, the basin west of Bermuda, the Bermuda Rise, the Nares Basin, the Outer Ridge, and the Puerto Rico Trench.Recent studies of submarine topography, deep sea sediments, and suboceanic crustal structure have emphasized the need for an accurate instrument of high resolution. The relationship between the seaward extension of submarine canyons and the gradients of the abyssal plains, in particular, can now be explored in detail. The data provided by this instrument greatly aid in the efficient utilization of deep sea corers, dredges and cameras, and in the intelligent interpretation of the data obtained from these and other instruments of oceanographic research.With further development of this instrument, it is anticipated that data will be obtainable on such phenomena as waves and tides in the deep ocean.