Sea floor engineering geomorphology: recent achievements and future directions

New mapping technology is providing perspectives of the sea floor “as if there were no ocean”, revealing that ocean floors exhibit a wide variety of relief, sediment properties, and active geologic processes such as erosion, faulting, fluid expulsion, and landslides. The development of coastal and offshore resources, such as oil and gas and minerals, involves sea floor engineering in remote, complex, and sometimes hazardous environments. Optimum engineering design and construction practice require detailed surveys of sea floor geomorphology, geologic conditions on the sea bed and to various depths beneath it, combined with geotechnical properties of the sediments and oceanographic information. Integrated site survey models attempt to predict conditions and process frequencies and magnitudes relevant to the engineering design lifetimes of sea floor installations, such as cables, pipelines, production platforms, as well as supporting coastal infrastructure such as jetties, wharves, bridges and harbors. Recent use of deep water areas for oil and gas production, pipelines, and cable routes are also showing that the “worldʹs greatest slopes”, beyond the continental shelves contain exciting, exotic, and enigmatic geomorphological features and processes. Safe and cost-effective engineering use of these regions depends upon exciting new technical and conceptual advances for understanding sea floor geomorphology — a task which has barely begun.