Hydrographic & Geophysical Surveys
Artist's rendition of typical swath bathymetry coverage of the seafloor. Courtesy of Reson, Inc.
Substructure conducts hydrographic and geophysical surveys to support a variety of activities: port and harbor maintenance (dredging), pipeline and cable crossing surveys, dam face inspections, archaeological recovery, and coastal engineering (beach erosion and replenishment studies).
Data types of interest include depth of seawater, the nature of seafloor material, magnetic anomalies, and the composition of sub-bottom strata.
Substructure utlilizes, among other tools, both multibeam and side-scan sonar, a magnetometer, and a sub-bottom profiler to compile the data required by our clients’ diverse needs.
Worlwide Hydrographic Surveys
Substructure has performed hydrographic surveys throughout the world. We have surveyed locations along the eastern seaboard of the United States from Maine to Florida, as well as international sites from Ireland to Peru.
Advanced Survey Vessels
Substructure is nearing completion of its latest and most advanced survey vessel. This vessel has an overall length of 31’6” and is equipped with a medium speed tractor jet drive system from North American Marine Jet. This medium speed jet has very little impeller cavitation at low speed and the jet drive shaft rides on bearings both fore and aft of the impeller, thus reducing any endplay and associated vibration.
Reason Seabat 8125 Multibeam Echosounder
The vessel itself is built to utilize the Reson SeaBat 8125 Multibeam Echosounder. This system is a 455 kHz sonar unit that is hull-mounted, although the array can be angled for surveys of dam faces or other vertically-oriented surfaces.
The system transmits 240 dynamically focused beams, measuring a 120 degree swath across the seafloor. With a depth resolution of 6 mm, an across-track beam width of 0.5 degrees, and an along-track beam width of 1 degree, the Reson SeaBat 8125 is capable of consistently providing IHO Special Order accuracy and USACE Special Order accuracy.
The Latest In Subsurface Data Acquisition
The Reson 8125, combined with an advanced navigation system, motion sensors, a sound velocity probe, and several ancillary components, makes up the backbone of the survey system onboard Substructure’s latest vessel. Coupling these with advanced magnetometer and sub-bottom profiler capabilities rounds out the technical package and provides for the latest in subsurface data acquisition.