Marine geophysical survey is a rapidly developing and changing field. Fundamentally it is concerned with providing detailed images of the seabed and the underlying sedimentary and rock layers.
A suite of different techniques is used to capture the detail. Each technique has its particular merits. No one is entirely sufficient in its own right, but used in combination the techniques make it possible to construct useful insight.
Bathymetry records the surface contours of the seabed. Side-scan sonar acquires an image of the seabed surface. Magnetometry identifies ferrous metal anomalies on the seabed and in the underlying deposits, as well as natural geological variations. Sub-bottom profiling or seismic survey detects variations of the underlying seabed layers, helping to distinguish sediments from rock, and sands from mud. It can also distinguish cultural indicators such as shipwreck in the right circumstances.
ADCO works closely with select marine hydrography companies to ensure that the correct suite of instruments is used on particular projects. ADCO examines the primary data acquired and provides experienced archaeological interpretation and assessment.
To complete detailed survey of known submerged sites, such as shipwrecks, quays and fishtraps, ADCO recommends the use of the sector-scan sonar. This device captures metrically accurate data underwater and facilitates the production of 3D-imaging, much like a laser scanner does on land. The underwater data can also be merged with data captured from above the waterline. To learn more about the sector scan sonar and to use it on your project, contact ADCO at info@adco-ie.com.
