IMI30: Advantages
Currently, researchers who desire to use NSF instruments to map areas of several thousand square kilometers with sufficient resolution to identify small fault scarps, lava flows, or submarine channels are limited to using the DSL-120. The meter-scale resolution of DSL-120 sidescan is ideal for detailed studies of outcrop-scale geological features such as eruptive vents and hydrothermal mounds on midocean ridges (Scheirer, 2000). However, DSL-120 has a maximum sidescan swath width of 1 km and is towed at ~1 knot, which make it an inefficient tool for surveying larger scale features. For instance, a 40 km x 100 km survey of a midocean ridge spreading segment requires at least 90 days of DSL-120 survey time.
The IMI-30 will survey the same 40 km x 100 km area in about 8 days, assuming a 6 km swath width and 2 knot tow speed. This is a conservative estimate, because faster towing speeds may be possible at midocean ridge depths, and wider swath widths may be possible over highly backscattering terrain. For comparison, Figure 1 shows the amount of seafloor that can be surveyed per hour by the DSL-120, the HAWAII MR-1, and the IMI-30. The IMI-30 will be able to survey at least 11 times the area of DSL-120 over a given period.
