There has been rapid growth in the requirement for environmental baseline and habitat surveys in the North Sea and elsewhere in the world during recent years, to the extent that these, rather than pre-engineering surveys, are increasingly becoming the main driver for seabed survey work carried out in advance of offshore developments. Seabed surveys for engineering applications and environmental considerations are conventionally treated as separate exercises for planning and data analysis purposes. Different groups of specialists often work independently despite the high degree of overlap between conventional geophysical, seabed sample and photographic datasets. Pre-engineering and environmental surveys have different objectives, but a more integrated approach to survey planning and consideration of preliminary results would lead to efficiencies in data collection and the early identification of constraints. By working more closely together, engineering geophysicists and environmental scientists can resolve the apparently contradictory interpretations sometimes made from geophysical and environmental datasets collected from the same area. Confidence in survey results would increase and value would be added to both pre-engineering and environmental conclusions.
Seabed surveys have been carried out routinely for many years to provide the information necessary for safe and efficient installation of offshore facilities, installations and infrastructure. Hydrographic and marine geophysical techniques produce datasets that provide essential information on water depths, seabed topography and the nature and distribution of seabed sediments. Seismic profilers define the seismic stratigraphy of foundation zone sediments which, when integrated with geotechnical information, provide soil province maps essential to the conceptual and detailed design of offshore structures. Because mainly of the demands of the offshore oil and gas industry, seabed surveys for pre-engineering purposes are a mature science, although substantial markets also exist in the subsea cable industry and, more recently, in the offshore renewables industry.
