Sound Basis for North Sea Platforms - Programming of Essential Geotechnical Surveys

Abstract

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc. Abstract This paper describes the general considerations underlying the planning of geotechnical investigations for offshore oil and gas platforms. The investigations are split into three phases. The first phase consists of a site selection survey; the second phase deals with detailed surveys at specific sites, and the third phase includes laboratory testing, foundation analysis, construction planning and foundation evaluation. Details are given of the scope of the investigations and the equipment which can be used. Introduction oil companies, developing offshore hydrocarbon fields are bound to time frames. As far as the geotechnical consultant is concerned, these schedules run from the first commercially exploitable strike through the phase of final design to the installation and subsequent operation of the offshore facilities. The consulting geotechnical surveyor must meet the target dates set by the oil companies, so that sufficient information is available first when decisions on the number, type and lay-out of structures have to be made and later during the design and construction phases. THE PROCESS OF PLANNING AND DESIGN OF OIL/GAS FACILITIES Reservoir engineers and civil engineers jointly consider the layout, number and type of the production facilities. This takes production facilities. This takes place in stages in the period between place in stages in the period between the first commercial exploitable strike, the sinking of additional step-out wells and the consequential reservoir evaluation. As more information becomes available, the civil engineer can consider alternatives as to the most suitable sites, within the leeway given by the reservoir engineer, and the types of structures. The final lay-out and choice of the structures will be a compromise between both civil and reservoir engineering requirements. Once this has been completed, the final design work can start.