Mobile offshore drilling unit, a method of using such a unit and a system comprising such a unit

A method of performing a plurality of well-processing tasks on a plurality of wells in the seafloor of an offshore oil or gas reservoir, the method comprising:

• positioning a mobile offshore drilling unit in a proximity of an offshore platform different from the mobile offshore drilling unit and located above the plurality of wells, the mobile offshore drilling unit defining one or more well centres and comprising a primary drill rig comprising a drill floor and a hoisting system for raising and lowering tubular equipment from/into at least one of the plurality of wells in the seafloor via one of said one or more well centres, wherein the mobile offshore drilling unit is a jack-up platform comprising a cantilever supporting said primary drill rig and configured to extend the cantilever above the offshore platform;
• providing a remote well-processing device positioned on said offshore platform different from the mobile offshore drilling unit at a position displaced from the one or more well centres defined by the mobile offshore drilling unit;
• operationally coupling the remote well-processing device to the mobile offshore drilling unit;
• performing, by the remote well-processing device positioned on the offshore platform displaced from the one or more well centres defined by the mobile offshore drilling unit and away from any cantilever of the mobile offshore drilling unit, the first well-processing task on the first well, assisted by the mobile offshore drilling unit via said operational coupling;
• and
• concurrently performing the second well-processing task on the second well, wherein the second well-processing task is performed by the mobile offshore drilling unit or by the primary drilling rig of the mobile offshore drilling unit.

A mobile offshore drilling unit defining one or more well centres and comprising a primary drill rig comprising:

• a drill floor and a hoisting system for raising and lowering tubular equipment through one of the one or more well centres defined by the mobile offshore drilling unit;
• wherein the mobile offshore drilling unit is a jack-up platform comprising a cantilever supporting said primary drill rig and configured to extend the cantilever supporting said primary drill rig and configured to extend the cantilever above an offshore platform different from the mobile offshore drilling unit;
• wherein the mobile offshore drilling unit is configured to establish an operational coupling with a remote well-processing device positioned on the offshore platform and at a position different from the well centre defined by the mobile offshore drilling unit and away from any cantilever of the mobile offshore drilling unit;
• and to assist in performing two or more concurrent well-processing tasks performed on respective wells of an offshore oil or gas reservoir;
• wherein at least a first one of said well-processing tasks is performed by said remote well-processing device and a second one of said well-processing tasks is performed by said primary drilling rig.