Geohazards need not be – redefining project risk

摘要

Much has been written, often in emotive terms, about the identification, investigation and potential project impact of geohazards. Experience now shows that they need not necessarily create the concerns that they do. Adopting a systematic approach to quantifying geohazard risk can minimise the time and cost impacts upon any field development. Based upon experience on projects in most of the world’s geohazard prone regions, including: ? Offshore Norway ? The Caspian Sea ? The Mediterranean ? West Africa ? Gulf of Mexico, the authors describe the Advanced Geohazard Evaluation System (AGES) approach, its philosophy, execution and benefits. Components of the approach include: a] A regional geohazards database b] Advanced seismic reprocessing, and inversion imaging c] Probabilistic risk analysis d] Tailored Data Acquisition e] Geotechnical modelling - physical and numerical f] Deterministic engineering analysis g] Seabed instrumentation and monitoring In the process, geohazards themselves may be redefined and their impacts reassessed. Soil salt content may for example, have a more detrimental effect on wells and facilities than seabed slope failure. Understanding these phenomena and their engineering impact is key to the process.