Substructure

Substructure is pleased to offer its hydrographic and geophysical survey capabilities, a logical extension of its many years of successful commercial diving, search-and-recovery, and marine design and fabrication operations. Whether it’s a focused, high-resolution survey to assess the condition of an underwater engineering structure, a broad-scale mapping effort to characterize a marine habitat or to help plan a dredging project, or a detailed search and recovery operation, Substructure has the personnel, tools, and experience to efficiently tackle a wide range of marine surveying applications.

Survey Personnel

Substructure offers a team of engineers, marine scientists, and computer specialists with extensive experience in a wide range of geophysical, oceanographic, and engineering marine survey operations. The senior hydrographer has spent over 25 years planning and conducting marine-related survey operations, with professional experience evenly divided among NOAA, the US Army Corps of Engineers, and a large commercial engineering and science firm. One of Substructure’s proven strengths is the ability to effectively complete challenging marine field operations; Substructure personnel have successfully mobilized and conducted survey and diving operations on a wide range of vessels throughout the world — from flat-bottom skiffs to large offshore survey ships. In addition to the experience necessary to effectively acquire the field data, Substructure has the required technical staff to successfully process and analyze the often complex data sets.

Substructure is also a commercial member of the nearby University of New Hampshire Center for Coastal and Ocean Mapping (CCOM), a national center for expertise in ocean mapping and hydrographic sciences. Substructure has participated in recent projects with CCOM and looks forward to the continued opportunities to collaborate with them in the future.

Survey Vessel Orion

Over a lengthy and well thought-out process, Substructure’s engineers and technicians designed and built an inshore survey platform that would allow them to efficiently and reliably acquire accurate, high-resolution seafloor characterization data. Survey vessel Orion was specifically designed around a system of Substructure-owned multibeam survey components to conduct near shore multibeam surveys capable of satisfying the International Hydrographic Organization’s (IHO) Special Order standards, while also enabling fast and predictable mobilizations.

The attention to detail during the design and development of Orion enables highly accurate and repeatable depth measurements that are critical for a range of applications. These design details, along with the ability to apply real-time kinematic DGPS tidal corrections and also acquire frequent speed–of-sound casts enable Substructure to acquire data exceeding the IHO Special Order standards; under well-controlled conditions it will be possible to provide repeatable vertical resolution on the order of only a few centimeters. These types of accuracies can be critical for dredging-volume computations, seafloor-change evaluations, and engineering and structural assessments.

Survey Techniques

The many techniques routinely employed during geophysical field operations include multibeam bathymetry, side-scan sonar and multibeam backscatter imaging, acoustic sub-bottom profiling, magnetic anomaly profiling, sediment profile imaging, underwater video imaging (towed and ROV), and a variety of sediment sampling and coring techniques. During water column measurement operations, these same techniques may be supplemented with a variety of surface- or bottom-mounted arrays, which might include current meters, water-level gauges, conductivity/temperature/depth probes, and a wide variety of other sensors.