Land rig on artificial island is one of the drilling rig concepts for offshore drilling in shallow water environments.
1. Water depth range: 0-10m. Costs rise significantly with water depth and distance from shore.
2. The environmental impact for marine life is potentially high. Island would disappear, with time, due to wave and ice effects. sheet piling used for retention it would need to be removed for island to dissipate.
3. Concept is particularly suitable for ice, but ice scour and ice rubble needs particular consideration. It is a proven concept in the Caspian and currently used by AGIP for the development of the Kashagan field. Perimeter of island should be protected against ice damage by berms, ice deflector and ice rubble makers.
4. Suitable for development. Cost may be prohibitive for exploration, particularly if island must be removed. Island design and construction can take up to 2 years and the Caspian infrastructure, limited quarries and construction barges may limit the number of island that can be constructed simultaneously.
5. Simple solution with very high local content, provided there is a quarry in the region with access to the sea.
6. Possibility to use a conventional land rig, with maximum flexibility in specification and lay out. Size of rig only limited by size of island
Other drilling rig design concepts for shallow water depth environments will include:
1. Land rig on artificial island
2. Land rig on barge (with optional submerged caissons)
3. Swamp Barge (With Optional Submerged Caissons)
8. Steel Caisson with Drilling Rig
9. Modularised and Pile Elevated Drilling Rig
10. Drilling Rig on Pre-Installed Piles and Modules
11. Jacket Supported Offshore Rig
12. Posted Barge With Land Or Modular Rig
13. Heli-Rig
14. Submersible