Maritime archaeology is a discipline within archaeology as a whole that specifically studies human interaction with the sea, lakes and rivers through the study of associated physical remains, be they vessels, shore-side facilities, port-related structures, cargoes, human remains and submerged landscapes. A specialty within maritime archaeology is nautical archaeology, which studies ship construction and use.
Underwater archaeology is archaeology practiced underwater. As with all other branches of archaeology, it evolved from its roots in pre-history and in the classical era to include sites from the historical and industrial eras.
In archaeology, excavation is the exposure, processing and recording of archaeological remains. An excavation site or "dig" is the area being studied. These locations range from one to several areas at a time during a project and can be conducted over a few weeks to several years.
Placer mining is the mining of stream bed (alluvial) deposits for minerals. This may be done by open-pit or by various surface excavating equipment or tunneling equipment.
A diving air compressor is a gas compressor that can provide breathing air directly to a surface-supplied diver, or fill diving cylinders with high-pressure air pure enough to be used as a breathing gas. A low pressure diving air compressor usually has a delivery pressure of up to 30 bar, which is regulated to suit the depth of the dive. A high pressure diving compressor has a delivery pressure which is usually over 150 bar, and is commonly between 200 and 300 bar. The pressure is limited by an overpressure valve which may be adjustable.
A vacuum ejector, or simply ejector is a type of vacuum pump, which produces vacuum by means of the Venturi effect.
Dredging is the excavation of material from a water environment. Possible reasons for dredging include improving existing water features; reshaping land and water features to alter drainage, navigability, and commercial use; constructing dams, dikes, and other controls for streams and shorelines; and recovering valuable mineral deposits or marine life having commercial value. In all but a few situations the excavation is undertaken by a specialist floating plant, known as a dredger.
A gas lift or bubble pump is a type of pump that can raise fluid between elevations by introducing gas bubbles into a vertical outlet tube; as the bubbles rise within the tube they cause a drop in the hydrostatic pressure behind them, causing the fluid to be pulled up. Gas lifts are commonly used as artificial lifts for water or oil, using compressed air or water vapor.
An injector is a system of ducting and nozzles used to direct the flow of a high-pressure fluid in such a way that a lower pressure fluid is entrained in the jet and carried through a duct to a region of higher pressure. It is a fluid-dynamic pump with no moving parts except a valve to control inlet flow.
An airlift is device based on a pipe, used in nautical archaeology to suck small objects, sand and mud from the sea bed and to transport the resulting debris upwards and away from its source. It is sometimes called a suction dredge. A water dredge or water eductor may be used for the same purpose.
A dust collector is a system used to enhance the quality of air released from industrial and commercial processes by collecting dust and other impurities from air or gas. Designed to handle high-volume dust loads, a dust collector system consists of a blower, dust filter, a filter-cleaning system, and a dust receptacle or dust removal system. It is distinguished from air purifiers, which use disposable filters to remove dust.
An airlift pump is a pump that has low suction and moderate discharge of liquid and entrained solids. The pump injects compressed air at the bottom of the discharge pipe which is immersed in the liquid. The compressed air mixes with the liquid causing the air-water mixture to be less dense than the rest of the liquid around it and therefore is displaced upwards through the discharge pipe by the surrounding liquid of higher density. Solids may be entrained in the flow and if small enough to fit through the pipe, will be discharged with the rest of the flow at a shallower depth or above the surface. Airlift pumps are widely used in aquaculture to pump, circulate and aerate water in closed, recirculating systems and ponds. Other applications include dredging, underwater archaeology, salvage operations and collection of scientific specimens.
The term wet scrubber describes a variety of devices that remove pollutants from a furnace flue gas or from other gas streams. In a wet scrubber, the polluted gas stream is brought into contact with the scrubbing liquid, by spraying it with the liquid, by forcing it through a pool of liquid, or by some other contact method, so as to remove the pollutants.
Aquarium filters are critical components of both freshwater and marine aquaria. Aquarium filters remove physical and soluble chemical waste products from aquaria, simplifying maintenance. Furthermore, aquarium filters are necessary to support life as aquaria are relatively small, closed volumes of water compared to the natural environment of most fish.
Salvage diving is the diving work associated with the recovery of all or part of ships, their cargoes, aircraft, and other vehicles and structures which have sunk or fallen into water. In the case of ships it may also refer to repair work done to make an abandoned or distressed but still floating vessel more suitable for towing or propulsion under its own power. The recreational/technical activity known as wreck diving is generally not considered salvage work, though some recovery of artifacts may be done by recreational divers.
Gatecliff Rockshelter (26NY301) is a major archaeological site in the Great Basin area of the western United States that provides remarkable stratigraphy; it has been called the "deepest archaeological rock shelter in the Americas". Located in Mill Canyon of the Toquima Range in the Monitor Valley of central Nevada, Gatecliff Rockshelter has an elevation of 7,750 feet (2,360 m). David Hurst Thomas discovered Gatecliff Rockshelter in 1970 and began excavations in 1971. Full scale excavations occurred at Gatecliff Rockshelter for about seven field seasons in which nearly 33 feet (10 m) of sediments were exposed for a well-defined stratigraphic sequence. The well-preserved artifacts and undisturbed sediments at Gatecliff Rockshelter provides data and information have been applied to a range of research topics. Based on the analysis of the artifacts at Gatecliff Rockshelter, it can be determined that it was most likely a short-term field camp throughout prehistory. The latest evidence for human usage at Gatecliff occurs between ca. 5500 B.P. to 1250 B.P.
The conservation and restoration of shipwreck artifacts is the process of caring for cultural heritage that has been part of a shipwreck. Oftentimes these cultural artifacts have been underwater for a great length of time. Without conservation, most artifacts would perish and important historical data would be lost. In archaeological terms, it is usually the responsibility of an archaeologist and conservator to ensure that material recovered from a shipwreck is properly cared for. The conservation phase is often time-consuming and expensive, which is one of the most important considerations when planning and implementing any action involving the recovery of artifacts from a shipwreck.
This page is a glossary of archaeology, the study of the human past from material remains.
Underwater work is work done underwater, generally by divers during diving operations, but includes work done underwater by remotely operated vehicles and crewed submersibles.
Archaeological diving is a type of scientific diving used as a method of survey and excavation in underwater archaeology. The first known use of the method comes from 1446, when Leon Battista Alberti explored and attempted to lift the ships of Emperor Caligula in Lake Nemi, Italy. Just a few decades later, in 1535, the very same site saw the first use of a sophisticated breathing apparatus for archaeological purposes, when Guglielmo de Lorena and Frances de Marchi used an early diving bell to explore and retrieve material from the lake, although they decided to keep the blueprint of the exact mechanism secret. The following three centuries saw the gradual extension of diving time through the use of bells and submersing barrels filled with air. In the 19th century, the hard-hat diving gear was developed, allowing divers to stay underwater for extended periods through a constant air supply pumped down from the surface through a hose. Nevertheless, the widespread utilisation of diving gear for archaeological purposes had to wait until the 20th century, when archaeologists began to appreciate the wealth of material that could be found under the water. This century also saw further advances in technology, most important being the invention of the aqualung by Émile Gagnan and Jacques-Yves Cousteau, the latter of whom would go on to use the technology for underwater excavation by 1948. Modern archaeologists use two kinds of equipment to provide them with air underwater: self-contained underwater breathing apparatus (SCUBA), which allows for greater mobility but limits the time the diver can spend in the water, and surface supplied diving equipment, which is safer but more expensive, and can only be used in shallower waters.
