Both types of rig can be used for drilling in the search for either oil or gas. Jack-ups have the advantage of being more stable than floaters but their use is restricted, given their limited downward reach, to shallow waters at a maximum depth of 400ft. Floaters, whether in the form of 'semi-submersibles' or 'drillships', are capable of operating in much deeper waters. The situation in the North Sea exemplifies the constraints posed by water depth. Jack-ups are used primarily in the shallower southern gas basins such as those found in waters off the English coast.
Floaters predominate in oilfields in the deeper northern waters offshore from Scotland and Norway.
The geographic market for mobile offshore drilling has a global dimension, given the inherently transportable nature of the rigs. Regulations imposed by the UK and the Norwegian governments exclude floaters that are not built to certain design specifications. For floaters that do not already meet with the regulatory standards, there are high sunk costs involved in making the necessary modifications. There being limitations on the entry of drilling rigs into northern waters, I have therefore focussed my assessment on the competitive situation in this region. Falcon also had an 'accommodation rig'.