A combination of an offshore marine structure and an auxiliary floating system for the installation and/or transport of said offshore marine structure, said offshore structure being provisionally or definitively self-floating and of the type that comprises an essentially vertical shaft, wherein said auxiliary floating system comprises: - a plurality of floating elements; - at least a coupling structure connected to said floating elements and configured to couple to the marine structure around the shaft thereof, wherein said coupling structure comprises an opening and closing subsystem to facilitate the placement on and/or removal thereof from the offshore structure, wherein the opening and closing subsystem comprises one or more articulations that allow for a rotation of the floating elements about said articulations with respect to an essentially vertical axis; and wherein the coupling structure is a modular or articulated structure connecting said floating elements. - one or more guide elements secured to the coupling structure which provide one or more sliding contact surfaces with said shaft; characterised in that the coupling structure comprises at least a ring adapted to surround the shaft of the offshore structure, and a plurality of lattice arms connecting said ring and the floating elements, wherein the guide elements are comprised in the ring and wherein the length of the lattice arms set the separation between the floating elements and the shaft; and in that the auxiliary floating system is configured such that, when the coupling structure is coupled to the offshore marine structure around the vertical shaft thereof: - the coupling structure allows for essentially free relative vertical movement between floating elements of the auxiliary floating system and the shaft such that if the offshore structure sinks, the auxiliary floating system remains at essentially the same level on the surface; and - the coupling structure limits and/or prevents other relative movements between the auxiliary floating system and the shaft, both in the relative horizontal movement and in the relative rotation during the roll, pitch or yaw. - a plurality of floating elements; - at least a coupling structure connected to said floating elements and configured to couple to the marine structure around the shaft thereof, wherein said coupling structure comprises an opening and closing subsystem to facilitate the placement on and/or removal thereof from the offshore structure, wherein the opening and closing subsystem comprises one or more articulations that allow for a rotation of the floating elements about said articulations with respect to an essentially vertical axis; and wherein the coupling structure is a modular or articulated structure connecting said floating elements. - one or more guide elements secured to the coupling structure which provide one or more sliding contact surfaces with said shaft; the coupling structure comprises at least a ring adapted to surround the shaft of the offshore structure, and a plurality of lattice arms connecting said ring and the floating elements, wherein the guide elements are comprised in the ring and wherein the length of the lattice arms set the separation between the floating elements and the shaft; and in that the auxiliary floating system is configured such that, when the coupling structure is coupled to the offshore marine structure around the vertical shaft thereof: - the coupling structure allows for essentially free relative vertical movement between floating elements of the auxiliary floating system and the shaft such that if the offshore structure sinks, the auxiliary floating system remains at essentially the same level on the surface; and - the coupling structure limits and/or prevents other relative movements between the auxiliary floating system and the shaft, both in the relative horizontal movement and in the relative rotation during the roll, pitch or yaw. - the coupling structure allows for essentially free relative vertical movement between floating elements of the auxiliary floating system and the shaft such that if the offshore structure sinks, the auxiliary floating system remains at essentially the same level on the surface; and - the coupling structure limits and/or prevents other relative movements between the auxiliary floating system and the shaft, both in the relative horizontal movement and in the relative rotation during the roll, pitch or yaw.