Archaeology of shipwrecks

The wreck of the Severance, a modern wreck with rigging intact.

Expedition to shipwreck in Tallinn Bay.

Side-scan sonar image of shipwreck "Aid" in Estonia.

The archaeology of shipwrecks is the field of archaeology specialised in the study and exploration of shipwrecks. Its techniques combine those of archaeology with those of diving.

It is necessary to understand the processes by which a wreck site is formed to take into account the distortions in the archaeological material caused by the filtering and scrambling of material remains that occurs during and after the wrecking process.

When a ship is wrecked, it suffers many changes of state until the remains eventually reach equilibrium with their environment. Initially, the wrecking process changes it from the human organised form of a working vessel to an unstable state of structure and artefacts underwater. Natural forces act upon it during the wrecking process and continue to act until equilibrium is reached. Heavy items sink rapidly, lighter items may drift before sinking, while buoyant items may float away completely. This causes a filtering and scrambling of the material remains. The sudden arrival of a structure on the seabed will change the currents, often resulting in new scour and deposition patterns in the seabed. Once underwater, chemical processes and the action of biological organisms will contribute to the disintegration. At any point in these processes, humans may have intervened, for example by salvaging items of value.

Prior to being wrecked, the ship would have operated as an organised machine, and its crew, equipment, passengers and cargo need to be considered as a system. The material remains should provide clues to the functions of seaworthiness, navigation and propulsion as well as to ship-board life.

Finally the ship as a means of transport can be considered as an element in a geographically dispersed social, political and economic system. Warships impose political will by force; cargo vessels exist in a system of commerce; while passenger carrying vessels give clues to social classes and structure. Social status may also exist within the ship, for example, segregation between officers and seamen.

UNESCO Convention on the protection of the Underwater Cultural Heritage

Shipwrecks that have been underwater for one hundred years or more are protected by the UNESCO Convention on the Protection of the Underwater Cultural Heritage. This convention aims at preventing looting and the destruction or loss of historic and cultural information.^[1] It helps states parties to protect their underwater cultural heritage with an international legal framework.^[2]

Archaeological theories of shipwrecks

Muckelroy's model

A systematic model for the characterisation and interpretation of the archaeology of shipwrecks was first proposed by Keith Muckelroy in 1976 ^[3] Muckelroy's system model describes the evolution of the material remains of the ship from the wrecking process, subsequent salvage operations and the disintegration and rearrangements of the remains from environmental factors. Although Muckelroy considered both natural processes and human activity in his model, subsequent research has mainly expanded the environmental factors and there has been little published on the human processes.

Considering human intervention

A paper by Martin Gibbs in 2006,^[4] expands Muckelroy's model to consider human behaviour at the time of the disaster and the long term relationship between people and shipwrecks. This model utilises studies of humans involved in disasters to characterise the human activity into phases around the time of the wrecking. This model considers:

Pre-impact threat phase, in which humans considering the risk may take avoiding action which results in there being no wreck, or may take unsuccessful action to mitigate the perceived threat, for example the wreck location may be the result of attempting to avoid some perceived greater threat. Stowage of cargo may also indicate consideration of threat.
Pre-impact warning phase, in which humans may take drastic action to avoid catastrophe, for example, running a vessel ashore, jettisoning cargo or running out anchors.
Impact, in which the decision is made to abandon ship or remain aboard, and, for example, attempt to refloat.
Post impact, where survivors regroup and, for example, salvage their own goods or make repairs.
Rescue and Post-disaster where the vessel is abandoned and in which third parties may be involved in salvage or in removing remains that present a hazard to navigation.

Footnotes

↑ UNESCO (ed.). "Convention on the protection of the Underwater Cultural Heritage - Text of the 2001 Convention". Retrieved 2016-02-04.
↑ UNESCO (ed.). "Underwater Cultural Heritage". Retrieved 2016-02-04.
↑ Muckleroy, K. (1976). "The integration of historical and archaeological data concerning an historic wreck site: The 'Kennemerland'". World Archaeology 7.3: 280–289. .
↑ Gibbs, M. "Cultural Site Formation Processes in Maritime Archaeology: Disaster Response, Salvage and Muckelroy 30 years". International Journal of Nautical Archaeology 35.1: 4–19.

External links

Lighthouse Archaeological Maritime Program (LAMP), St. Augustine Lighthouse and Museum, St. Augustine, Florida
Centre for Maritime Archaeology, University of Ulster, Coleraine
Shipwrecks UK: information on wrecks in the seas surrounding Britain and Ireland
The Sextant, Online community of Underwater Archaeology and Maritime History
Sea Research Society Ethics in Underwater Archaeology and Socialism versus Capitalism in Underwater Archaeology by Dr. E. Lee Spence
Institute of Nautical Archaeology
Institute of Maritime History
Nordic Underwater Archaeology
Flinders University Maritime Archaeology Program
A Code of Ethics for Maritime Archaeologists by Australian AIMA
[Richard Stillwell, ed. Princeton Encyclopedia of Classical Sites, 1976:] Richard Stillwell, ed. Princeton Encyclopedia of Classical Sites, 1976:]"Shipwrecks" Includes alphabetized list of known wreck sites from Classical Antiquity.

Types of ships and boats

Sailing vessels and rigs	Barque Barquentine Bermuda rig Bilander Brig Brigantine Caravel Carrack Catamaran Catboat Clipper Dutch clipper Coble Cog Corvette Cutter Dhow East Indiaman Fifie Fluyt Fore & Aft rig Frigate Full rigged ship Gaff rig Galiot Galleon Gunter Rig Hermaphrodite brig Jackass-barque Junk Ketch Longship Mersey Flat Multihull Nao Norfolk wherry Pink Pocket cruiser Polacca Pram Proa Sailing hydrofoil Schooner Ship of the line Sloop Smack Snow Square rig Tall ship Thames sailing barge Trimaran Vinta Wherry Windjammer Windsurfer Xebec Yacht Yawl

Military vessels	Aircraft carrier Amphibious assault ship Armed merchantman Auxiliary ship Battlecruiser Battleship Corvette Cruiser Destroyer Frigate Hospital ship Landing craft Mine countermeasures vessel Minelayer Missile boat Monitor Patrol boat Royal Yacht Ship of the line Sloop-of-war Submarine Submarine tender Survey ship Torpedo boat Trawler

Merchant vessels: Steamships and motor vessels	Bulk carrier Catamaran Container ship Cruiseferry Cruise ship Ferry Fireboat Hovercraft Hydrofoil Lifeboat Lightvessel Ocean liner Paddle steamer Rigid-hulled inflatable boat Roll-on/Roll-off Supertanker Surface effect ship Tanker Towboat Train ferry Trawler Tugboat Water taxi Whaler

Unpowered vessels and smaller boats	Barge Birlinn Bull Boat Cable ferry Canoe Coracle Currach Dinghy Dory Dragon boat Dredger Dugout Galley Gondola Kayak Lifeboat Lighter Outrigger canoe Parisal Punt Raft Reaction ferry Rowboat Sampan Whaleboat

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