Abstract: A bumper system is disclosed for docking an auxiliary drilling vessel to a compliant platform through first and second pads having vertically extending, complementary outboard faces presented from the respective structures in vertically slidable abutment. A biasing system pushes the vessel and platform into abutment across the first and second pads and the system allows the vessel to dock to the structure in a manner such that vertical loading is not substantially transmitted between the vessel and the structure across the sliding engagement.

Abstract: A method and system are disclosed for establishing hydrocarbon production for offshore reservoirs in which a compliant platform is installed at a selected site, an offshore drilling vessel is docked to the compliant platform and the vessel is positioned over a selected well site for conducting drilling operations, and the production riser is transferred from the vessel to the compliant platform and secured there. Communication between a surface tree installed on the production riser and facilities supported by the compliant platform is established and these steps are repeated for each selected well site served by the compliant platform.

Abstract: A method for building and assembling an offshore platform whose normal draft exceeds the depth of waterways between the building site and use location of the platform. The hull and deck of the platform are built separately in a shallow graving dock. The deck is then elevated, the graving dock partially flooded and the hull floated into position and mated to the deck. A modified form of the invention is the building of the hull and deck as a single structure and use of the barge to support a portion of the weight of the platform. The graving dock is then flooded to maximum depth, a barge is floated under the deck and ballasted down to a select draft. The barge is attached to the deck and then deballasted to partially support the platform structure and reduce its overall draft.

Abstract: A method is disclosed for conducting offshore well operations from an auxiliary vessel in support of a compliant platform. The auxiliary offshore drilling vessel is restrained with respect to the compliant platform in position adjacent the well bay of the compliant platform and vertically aligned with a selected well site for conducting well operations.

Abstract: A method is disclosed for conducting offshore well operations from an auxiliary vessel in support of a compliant platform. The auxiliary offshore drilling vessel is docked to the compliant platform and is positioned over a selected well site for conducting drilling operations by driving the compliant platform out of alignment as necessary to bring the well operations facilities of the auxiliary vessel docked thereto into substantially vertical alignment. The production riser is transferred from the auxiliary vessel to the compliant platform after well operations are complete.

Abstract: A method are disclosed for establishing hydrocarbon production for offshore reservoirs in which a compliant platform is installed at a selected site, an offshore drilling vessel is docked to the compliant platform and the vessel is positioned over a selected well site for conducting drilling operations, and the production riser is transferred from the vessel to the compliant platform and secured there. Communication between a surface tree installed on the production riser and facilities supported by the compliant platform is established and these steps are repeated for each selected well site served by the compliant platform.

Abstract: A tension leg well jacket ("TLWJ") is disclosed which is configured to receive well operations support from an offshore drilling vessel docked thereto and to receive the production riser in transfer operations from the vessel to the TLWJ. This permits a minimal platform suitable for supporting production risers which is particularly useful in deep water applications.

Abstract: A method and apparatus for positioning an offshore well substructure on the ocean floor. A substructure having a heigth of 1350 feet and base of 400 feet by 480 feet is subject to significant lateral forces caused by wind, wave, and current forces between the time period of lowering it to the ocean floor and driving piles through its skirt sleeves and into the ocean floor. Mudmats carried by the bottom corners of the substructure have downwardly-extending peripheral walls which penetrate the ocean floor so as to resist any lateral force to which the substructure is subjected. The base of a mudmat is approximately 10,000 square feet and the walls are approximately five feet high. A manifold system carried by each mudmat provides the capability of adjusting the level of the substructure after it has been lowered onto the ocean floor.

Abstract: A method and apparatus are disclosed for use in the installation of a platform structure upon the upper elements of a previously-installed substructure. The platform structure is mounted on a barge positionable between the upper elements of the previously-installed substructure. The barge can be flooded and lowered a sufficient distance to allow leg elements of the platform structure to contact and mate with leg support elements of the substructure.Impacts between the structures during the mating operation are absorbed by resilient neoprene pads carried by the leg supports. After the platform structure rests upon the leg supports, and the barge is removed, the platform structure can be lowered and leveled by draining a select volume of sand from the leg supports.