Editing Anchor (section)

===Multiple anchor patterns===
When it is necessary to moor a ship or floating platform with precise positioning and alignment, such as when drilling the seabed, for some types of salvage work, and for some types of diving operation, several anchors are set in a pattern which allows the vessel to be positioned by shortening and lengthening the scope of the anchors, and adjusting the tension on the rodes. The anchors are usually laid in prearranged positions by an anchor tender, and the moored vessel uses its own winches to adjust position and tension.<ref>{{cite report |url=https://assets.publishing.service.gov.uk/media/5a7a2ac2e5274a319e77853e/SD_SEA2EandP.pdf |title=An overview of offshore oil and gas exploration and production activities |page=8 |date=August 2001 |publisher=Department of Trade and Industry, UK }}</ref>

Similar arrangements are used for some types of [[single buoy mooring]]s, like the [[catenary anchor leg mooring]] (CALM) used for loading and unloading liquid cargoes.