Oil and Gas platforms are large fixed structures that are fixed to the seabed.They are either built on steal legs that are piled into the seabed or sitting on concrete bases .They are only used in shallow waters up to 457 meters .Some have facilities to drill wells.Then they extract and process the oil or natural Gas, Its then pumped ashore via large diameter pipes on the seabed to a refinery ashore then on to marketing
Ninian Central Platform is an oil platform in the North sea .When constructed in Loch Kishorn Scotland in 1978 the 600,000 tonne platform was the worlds largest man made movabe object.Before being towed to its current position and fixed to the sea floor .It is Circular concrete gravity structure 140m in diameter at its base with seven concentric walls of stepped heights intersected by radial walls at 45 degree angles.A 14m wide central shaft is surrounded by a breakwater wall (Jarlin Wall ) 45m in diameter and 1.6m thick pieced with 1.5 diameter holes.Between these two walls drill slots are arranged for drilling upto 42 wells.Originally operated by Chevron Petroleum UK a division of Chevron ,it is currently operated by CNR International
