INTERFEROMETRY An integrated approach to achieving high resolution, wide swath bathymetrical measurements

A number of Cape Town based, West Coast, marine diamond mining companies have<br>been established in the last few years. The requirement to service these companies has<br>resulted in the rapid growth in the knowledge and techniques required to identify<br>prospective marine diamond placer targets on the inner shelf<br>A decade ago most bathymetrical surveys used single echo sounders coupled to a<br>heave swell compensator. Subsequent to this, multibeam swath systems were<br>introduced to the marine mineral, diamond, oil and gas exploration and engineering<br>markets as a new survey technique to gather sonar data in swaths allowing more<br>density and greater range.<br>Although multibeam swath systems are a huge step forward in technology, their<br>usefulness is limited at far ranges where beam spreading occurs. For this reason,<br>Interferometry was developed as an alternative technique of acquiring bathymetry<br>soundings providing a greater data density and range than a conventional multibeam<br>swath system, thereby decreasing survey time and cost.