This paper discusses development of bottom-founded platforms for conventional deep-water drilling and production operations. Major design and construction considerations for deep-water pile-founded structures are presented. Approaches to responding to these considerations are illustrated with some aspects of the Hondo and Cognac platforms; these two installations extended platform opzrations to 259 and 312 m, respectively. North Sea developments with deep-water application are briefly summarized. The paper also discusses guyed towers, a new platform concept capable of conventional drilling and production operations in water depths of at least 600 m. Results of a major offshore field test of the guyed tower are given.
Cette étude examine le développement des plates-formes fixées au fond pour les opérations de forage et de production classiques. Les facteurs importants dans la conception et la construction des structures sur piles en eau profonde sont étudiés. On présente des solutions à ces problèmes qui sont illustrées par quelques caractéristiques des plates-formes HONDO et COGNAC. Ces deux installations ont permis d'étendre les opérations des plates-formes jusqu'à 259 et 312 m de profondeur d'eau respectivement. Les développements en mer du Nord avec des applications en mer profonde sont brièvement résumés. On étudie égaiement les plates-formes haubanées, nouveau style de plate-forme capable de faire du forage classique et des opérations de production en mer profonde jusqu'a 600 m au moins. On donne le résultat d'un essai de plate-forme haubanée sur un important gisement offshore.
Extensive operations over more than 30 years have established use of fixed, bottom-founded platforms as a conventional method for offshore oil and gas development. These platforms provide a stable area for conduct of drilling and production operations. More than 850 platforms in the Gulf of Mexico alone have provided a base for development of technology.
Evolution of platforms has followed the general trend of exploratory drilling toward deeper water and greater capability. In the 1970s, North Sea operations reached water depths in a range around 140 m with platforms characterized by marked growth in deck load, number of wells, and consequent overall size. For these operations, capability to fabricate and install very large steel platforms developed, and concrete gravity platforms were introduced. Since 1976, the Hondo platform in the Santa Barbara Channel, California, and the Cognac platform in the Gulf of Mexico have brought major advances in water depths for fixed platforms; these platforms are installed in water depths of 259 and 312 m, respectively.
For Hondo and Cognac, owner companies elected to use a basis of proven
