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77-877: The Nautical Archaeology Program offers admission to students seeking graduate degrees in nautical archaeology . The primary focus is on training archaeologists to become divers, rather than teaching divers the principles of anthropology and archaeology. Students are also required to learn the principles of archaeological conservation, with primary emphasis on the treatment of waterlogged artifacts. The program has six full-time faculty members and many research associates who conduct surveys, excavations, conservation and reconstruction of ancient, medieval, and early modern shipwrecks. Each professor holds an endowed fellowship. All NAP students are required to take several core courses: History of Wooden Shipbuilding, Research and Reconstruction of Ships, Conservation of Cultural Resources, and Archaeological Methods and Theory. The average time to complete

154-447: A body of water and usually juts out from its shore , typically supported by piles or pillars , and provides above-water access to offshore areas. Frequent pier uses include fishing , boat docking and access for both passengers and cargo , and oceanside recreation . Bridges, buildings, and walkways may all be supported by architectural piers . Their open structure allows tides and currents to flow relatively unhindered, whereas

231-618: A 60-metre (200 ft) high bungee jump over the North Sea waves. The present pier is a successor of an earlier pier, which was completed in 1901 but in 1943 destroyed by the German occupation forces. The first recorded pier in England was Ryde Pier , opened in 1814 on the Isle of Wight , as a landing stage to allow ferries to and from the mainland to berth. It is still used for this purpose today. It also had

308-538: A great deal of human activity that had been gathered round what had been an enormous, fresh-water lake. Significant cave art sites off the coast of western Europe such as the Grotto Cosquer can be reached only by diving, because the cave entrances are underwater, though the upper portions of the caves themselves are not flooded. Throughout history, seismic events have at times caused submergence of human settlements. The remains of such catastrophes exist all over

385-623: A leisure function in the past, with the pier head once containing a pavilion, and there are still refreshment facilities today. The oldest cast iron pier in the world is Town Pier, Gravesend , in Kent , which opened in 1834. However, it is not recognised by the National Piers Society as being a seaside pier. Following the building of the world's first seaside pier at Ryde, the pier became fashionable at seaside resorts in England and Wales during

462-647: A linear littoral quayside, and such piers are usually much shorter. Typically each pier would carry a single transit shed the length of the pier, with ships berthing bow or stern in to the shore. Some major ports consisted of large numbers of such piers lining the foreshore, classic examples being the Hudson River frontage of New York , or the Embarcadero in San Francisco . The advent of container shipping , with its need for large container handling spaces adjacent to

539-530: A master's degree is three to five years; for a Ph.D. the average is five to seven years. The program admits between eight and ten students each year. Graduating students are awarded their M.A. or Ph.D. in Anthropology. The Nautical Archaeology Program began after the Institute of Nautical Archaeology (INA) became affiliated with Texas A&M University in 1976. As part of the affiliation, Texas A&M established

616-471: A new pier was built in 1933. It remained till the present day, but was partially transformed and modernized in 1999–2004. In Nieuwpoort, Belgium there is a pleasure pier on both sides of the river IJzer . Scheveningen , the coastal resort town of The Hague , boasts the largest pier in the Netherlands , completed in 1961. A crane, built on top of the pier's panorama tower, provides the opportunity to make

693-563: A period of years, as is the case with port-related structures (such as piers , wharves , docks and jetties ) where objects are lost or thrown off structures over extended periods of time. This fact has led to shipwrecks often being described in the media and in popular accounts as ' time capsules '. Archaeological material in the sea or in other underwater environments is typically subject to different factors than artifacts on land. However, as with terrestrial archaeology, what survives to be investigated by modern archaeologists can often be

770-556: A pier has two decks. Galveston Island Historic Pleasure Pier in Galveston , Texas has a roller coaster, 15 rides, carnival games and souvenir shops. Early pleasure piers were of complete timber construction, as was with Margate which opened in 1824. The first iron and timber built pleasure pier Margate Jetty , opened in 1855. Margate pier was wrecked by a storm in January 1978 and not repaired. The longest iron pleasure pier still remaining

847-451: A pier presents a set of different circumstances to fishing from the shore or beach, as you do not need to cast out into the deeper water. This being the case there are specific fishing rigs that have been created specifically for pier fishing which allow for the direct access to deeper water. In Blankenberge a first pleasure pier was built in 1894. After its destruction in the World War I ,

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924-420: A ship, the destruction of a town by a seismic event can take place over many years and there may be evidence for several phases of damage, sometimes with rebuilding in between. 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

1001-486: A strong maritime culture such as the United Kingdom , the Netherlands , Denmark , Portugal and Spain were able to establish colonies on other continents. Wars were fought at sea over the control of important resources. The material cultural remains that are discovered by maritime archaeologists along former trade routes can be combined with historical documents and material cultural remains found on land to understand

1078-491: A sub-discipline of aviation archaeology , underwater aviation archaeology is also practised in the region. In some states maritime and underwater archaeology is practised out of Museums and in others out of cultural heritage management units, and all practitioners operate under the aegis of the Australasian Institute for Maritime Archaeology (AIMA). Pier A pier is a raised structure that rises above

1155-522: A three-tier hierarchy, of which the first tier considers the wrecking process itself: how does a ship break up, how does a ship sink to the bottom, and how do the remains of the ship, cargo and the surrounding environment evolve over time? The second tier studies the ship as a machine, both in itself and in a military or economic system. The third tier consists of the archaeology of maritime cultures, in which nautical technology, naval warfare , trade and shipboard societies are studied. Some consider this to be

1232-458: A tiny fraction of the material originally deposited. A feature of maritime archaeology is that despite all the material that is lost, there are occasional rare examples of substantial survival, from which a great deal can be learned, due to the difficulties often experienced in accessing the sites. There are those in the archaeology community who see maritime archaeology as a separate discipline with its own concerns (such as shipwrecks) and requiring

1309-400: A very large amount of material, buried in the sediments, remained to be found by maritime archaeologists of the twentieth century. While preservation in situ is not assured, material that has survived underwater and is then recovered to land is typically in an unstable state and can only be preserved using highly specialised conservation processes. While the wooden structure of Mary Rose and

1386-441: Is underwater archaeology , which studies the past through any submerged remains be they of maritime interest or not. An example from the prehistoric era would be the remains of submerged settlements or deposits now lying under water despite having been dry land when sea levels were lower. The study of submerged aircraft lost in lakes, rivers or in the sea is an example from the historical, industrial or modern era. Another example are

1463-623: Is at Southend-on-Sea , Essex , and extends 1.3 miles (2.1 km) into the Thames Estuary . The longest pier on the West Coast of the US is the Santa Cruz Wharf , with a length of 2,745 feet (837 m). Providing a walkway out to sea, pleasure piers often include amusements and theatres as part of their attractions. Such a pier may be unroofed, closed, or partly open and partly closed. Sometimes

1540-526: Is considered the earliest deep-sea shipwreck to be discovered. An example of maritime archaeology in the Pacific Ocean is the discovery of the wreck of Two Brothers , discovered in 2008 by a team of marine archaeologists working on an expedition for the National Oceanic and Atmospheric Administration (NOAA). The identity of the ship was not immediately known so it was called the "Shark Island Whaler";

1617-524: Is little energy available for either organic activity or chemical reactions. Salt water provides for greater organic activity than freshwater, and in particular, the shipworm , Teredo navalis , lives only in salt water, so some of the best preservation in the absence of sediments has been found in the cold, dark waters of the Great Lakes in North America and in the (low salinity) Baltic Sea (where Vasa

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1694-482: Is often fragile with no remaining metal within the layer of concretion and corrosion products. USS  Monitor , having been found in the 1970s, was subjected to a program of attempted in situ preservation, for example, but deterioration of the vessel progressed at such a rate that the rescue of her turret was undertaken lest nothing be saved from the wreck. Some wrecks, lost to natural obstacles to navigation, are at risk of being smashed by subsequent wrecks sunk by

1771-459: Is presently considered somewhat anomalous, in that after two decades of treatment it can now be turned over by hand. A challenge for the modern archaeologist is to consider whether in-situ preservation, or recovery and conservation on land is the preferable option; or to face the fact that preservation in any form, other than as an archaeological record is not feasible. A site that has been discovered has typically been subjected to disturbance of

1848-477: Is the one at Southend. First opened as a wooden pier in 1829, it was reconstructed in iron and completed in 1889. In a 2006 UK poll, the public voted the seaside pier onto the list of icons of England. Many piers are built for the purpose of providing boatless anglers access to fishing grounds that are otherwise inaccessible. Many "Free Piers" are available in larger harbors which differ from private piers. Free Piers are often primarily used for fishing. Fishing from

1925-635: The Salcombe B site . A close collection of artefacts on the sea bed may imply that artefacts were from a ship, even if there are no remains of the actual vessel. Late Bronze Age ships, such as the Uluburun Shipwreck have been discovered in the Mediterranean, constructed of edge joined planks. This shipbuilding technology continued through the classical period. The 2023 announcement of the Orca Shipwreck

2002-613: The Victorian era , peaking in the 1860s with 22 being built in that decade. A symbol of the typical British seaside holiday, by 1914, more than 100 pleasure piers were located around the UK coast. Regarded as being among the finest Victorian architecture, there are still a significant number of seaside piers of architectural merit still standing, although some have been lost, including Margate , two at Brighton in East Sussex , one at New Brighton in

2079-498: The health of sandy beaches and navigation channels . Pleasure piers were first built in Britain during the early 19th century. The earliest structures were Ryde Pier , built in 1813/4, Trinity Chain Pier near Leith, built in 1821, Brighton Chain Pier , built in 1823. and Margate Jetty 1823/24 originally a timber built pier. Only the oldest of these piers still remains. At that time,

2156-507: The "portus Julius" created by Marcus Vipsanius Agrippa in 37 BC, later sunk due to bradyseism . The sea floor elsewhere in the Mediterranean holds countless archaeological sites. In Israel , Herod the Great 's port at Caesarea Maritima has been extensively studied. Other finds are consistent with some passages of the Bible (like the so-called Jesus boat , which appears to have been in use during

2233-507: The 1st century BC and may have been dispatched by the Roman general, Sulla , to carry booty back to Rome. The sponge divers also recovered from the wreck the famous Antikythera mechanism , believed to be an astronomical calculator. Further examples of fabulous works of art recovered from the sea floor are the two "bronzi" found in Riace ( Calabria ), Italy. In the cases of Antikythera and Riace, however,

2310-548: 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 breathing gas underwater: self-contained underwater breathing apparatus (SCUBA) , which allows for greater mobility but limits

2387-616: The Center for the Study of the First Americans (CSFA), a highly regarded research institute affiliated with Texas A&M which works closely with the terrestrial archaeologists in the Anthropology department. The staff of six full-time professors of Nautical Archaeology makes the NAP one of the largest academic programs in nautical archaeology in the world. NAP professors direct most of INA's projects, since

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2464-600: The Nautical Archaeology Program as a separate entity. Since the first excavations INA carried out were in the Mediterranean, the main focus was initially on Old World nautical archaeology; after affiliating with the University, a New World archaeologist joined the staff, and work began in North America and Africa. The establishment of a department dedicated to the discipline allowed nautical archaeology to develop into an important subfield of archaeology. In 2005,

2541-485: The Okeanos Gas Gathering Company (OGGC). Large pipelines can crush sites and render some of their remnants inaccessible as pipe is dropped from the ocean surface to the substrate thousands of feet below. Trawl nets snag and tear superstructures and separate artifacts from their context. The wrecks, and other archaeological sites that have been preserved have generally survived because the dynamic nature of

2618-604: The States and the Commonwealth under their shipwreck legislation. Studies now include as an element of underwater archaeology, as a whole, the study of submerged indigenous sites. Nautical Archaeology, (the specialised study of boat and ship construction) is also practised in the region. Often the sites or relics studied in Australia as in the rest of the world are not inundated. The study of historic submerged aircraft, better known as

2695-631: The Texas A&;M University System Board of Regents established the Center for Maritime Archaeology and Conservation (CMAC), a research center intended to be the main mechanism of cooperation between the Nautical Archaeology Program and the Institute of Nautical Archaeology. All of the laboratories once part of the Nautical Archaeology Program are now administered by CMAC. CMAC is meant to be the Nautical counterpart of

2772-594: The U.S. Navy deep submergence research submarine NR-1 discovered the sites in 1997. In 1999 a team led by Robert Ballard and Harvard University archaeology Professor Lawrence Stager investigated the wrecks. Extensive research has been carried out on the Mediterranean and Aegean coastlines of Turkey. Complete excavations have been performed on several wrecks from the Classical , Hellenistic , Byzantine , and Ottoman periods. Maritime archaeological studies in Italy illuminate

2849-511: The artifacts were recovered without the direct participation of maritime archaeologists. Recent studies in the Sarno river (near Pompeii ) show other interesting elements of ancient life. The Sarno projects suggests that on the Tyrrhenian shore there were little towns with palafittes , similar to ancient Venice . In the same area, the submerged town of Puteoli ( Pozzuoli , close to Naples ) contains

2926-520: The cost of proper and complete archaeological investigation may be too great to enable this to occur within a timescale that ensures that an archaeological record is made before data is inevitably lost. Maritime archaeology studies prehistorical objects and sites that are, because of changes in climate and geology , now underwater. Bodies of water, fresh and saline, have been important sources of food for people for as long as we have existed. It should be no surprise that ancient villages were located at

3003-518: The discovery of a canoe near St Botolphs. Examples of sewn-plank boats include those found at North Ferriby and the Dover Bronze Age Boat which is now displayed at Dover Museum . These may be an evolution from boats made of sewn hides, but it is highly unlikely that hide boats could have survived. Ships wrecked in the sea have probably not survived, although remains of cargo (particularly bronze material) have been discovered, such as those at

3080-470: The dynamic forces present. Thus rocky coastlines, especially in shallow water, are typically inimical to the survival of artifacts, which can be dispersed, smashed or ground by the effect of currents and surf, possibly (but not always) leaving an artifact pattern but little if any wreck structure. Saltwater is particularly inimical to iron artefacts including metal shipwrecks, and sea organisms will readily consume organic material such as wooden shipwrecks. On

3157-414: The economic, social and political environment of the past. Of late maritime archaeologists have been examining the submerged cultural remains of China , India , Korea and other Asian nations. There are significant differences in the survival of archaeological material depending on whether a site is wet or dry, on the nature of the chemical environment, on the presence of biological organisms and on

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3234-403: The end of their life, ships were often beached. Valuable or easily accessed timber has often been salvaged leaving just a few frames and bottom planking. Archaeological sites can also be found on the foreshore today that would have been on dry land when they were constructed. An example of such a site is Seahenge , a Bronze Age timber circle. The archaeology of shipwrecks can be divided into

3311-540: The first century AD). Maritime archaeology in Australia commenced in the 1970s with the advent of Jeremy Green due to concerns expressed by academics and politicians with the rampant destruction of the Dutch and British East India ships lost on the west coast. As Commonwealth legislation was enacted and enforced after 1976 and as States enacted their own legislation the sub-discipline spread throughout Australia concentrating initially on shipwrecks due to on-going funding by both

3388-582: The fishing and cargo industries and serves as a port for large cruise ships in the area. Many other working piers have been demolished, or remain derelict, but some have been recycled as pleasure piers. The best known example of this is Pier 39 in San Francisco . At Southport and the Tweed River on the Gold Coast in Australia , there are piers that support equipment for a sand bypassing system that maintains

3465-409: The gradual extension of diving time through the use of bells and submersing barrels filled with air. In the 19th century, the standard copper helmet 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

3542-564: The image of a Victorian cast iron pleasure pier. However, the earliest piers pre-date the Victorian age . Piers can be categorized into different groupings according to the principal purpose. However, there is considerable overlap between these categories. For example, pleasure piers often also allow for the docking of pleasure steamers and other similar craft, while working piers have often been converted to leisure use after being rendered obsolete by advanced developments in cargo-handling technology. Many piers are floating piers, to ensure that

3619-409: The individual artifacts have been undergoing conservation since their recovery, Holland 1 provides an example of a relatively recent (metal) wreck for which extensive conservation has been necessary to preserve the hull. While the hull remains intact, its machinery remains inoperable. The engine of SS  Xantho that was recovered in 1985 from a saline environment after over a century underwater

3696-453: The introduction of steamships and railways for the first time permitted mass tourism to dedicated seaside resorts . The large tidal ranges at many such resorts meant that passengers arriving by pleasure steamer could use a pier to disembark safely. Also, for much of the day, the sea was not visible from the shore and the pleasure pier permitted holidaymakers to promenade over and alongside the sea at all times. The world's longest pleasure pier

3773-477: The more solid foundations of a quay or the closely spaced piles of a wharf can act as a breakwater , and are consequently more liable to silting. Piers can range in size and complexity from a simple lightweight wooden structure to major structures extended over 1,600 m (5,200 ft). In American English , a pier may be synonymous with a dock . Piers have been built for several purposes, and because these different purposes have distinct regional variances,

3850-476: The most important tier. Ships and boats are not necessarily wrecked: some are deliberately abandoned, scuttled or beached. Many such abandoned vessels have been extensively salvaged. The earliest boats discovered date from the Bronze Age and are constructed of hollowed out logs or sewn planks. Vessels have been discovered where they have been preserved in sediments underwater or in waterlogged land sites, such as

3927-406: The most notable, RMS  Titanic , though a relatively young wreck and in deep water so calcium-starved that concretion does not occur, appears strong and relatively intact, though indications are that it has already incurred irreversible degradation of her steel and iron hull. As such degradation inevitably continues, data will be forever lost, objects' context will be destroyed and the bulk of

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4004-490: The naval and maritime activities of the Etruscans , Greek colonists, and Romans . After the 2nd century BC, the Roman fleet ruled the Mediterranean and actively suppressed piracy. During this Pax Romana , seaborne trade increased significantly throughout the region. Though sailing was the safest, fastest, and most efficient method of transportation in the ancient world, some fractional percentage of voyages ended in shipwreck. With

4081-481: The other hand, out of all the thousands of potential archaeological sites destroyed or grossly eroded by such natural processes, occasionally sites survive with exceptional preservation of a related collection of artifacts. An example of such a collection is Mary Rose . Survival in this instance is largely due to the remains being buried in sediment Of the many examples where the sea bed provides an extremely hostile environment for submerged evidence of history, one of

4158-461: The pier stretching far enough off shore to reach deep water at low tide. Such piers provided an economical alternative to impounded docks where cargo volumes were low, or where specialist bulk cargo was handled, such as at coal piers . The other form of working pier, often called the finger pier, was built at ports with smaller tidal ranges. Here the principal advantage was to give a greater available quay length for ships to berth against compared to

4235-603: The piers raise and lower with the tide along with the boats tied to them. This prevents a situation where lines become overly taut or loose by rising or lowering tides. An overly taut or loose tie-line can damage boats by pulling them out of the water or allowing them so much leeway that they bang forcefully against the sides of the pier. Working piers were built for the handling of passengers and cargo onto and off ships or (as at Wigan Pier ) canal boats. Working piers themselves fall into two different groups. Longer individual piers are often found at ports with large tidal ranges , with

4312-445: The range of ocean depth, but most sites that are accessible to diving work are relatively shallow. The wreck of a Phoenician ship off the coast of Malta at a depth of about 110 metres (360 ft) has been partially excavated by divers using rebreather equipment , using techniques developed for the purpose to make the most effective use of time on site, which was restricted to 3 shifts of 12 minute each per day on site. The site of

4389-437: The remains of discovered and potential medieval bridges connecting the islands on the lake with the mainland. Many specialist sub-disciplines within the broader maritime and underwater archaeological categories have emerged in recent years. Maritime archaeological sites often result from shipwrecks or sometimes seismic activity , and thus represent a moment in time rather than a slow deposition of material accumulated over

4466-554: The same hazard, or are deliberately destroyed because they present a hazard to navigation. Even in deep water, commercial activities such as pipe-laying operations and deep sea trawling can place a wreck at risk. Such a wreck is the Mardi Gras shipwreck sunk in the Gulf of Mexico in 4,000 feet (1,200 m) of water. The shipwreck lay forgotten at the bottom of the sea until it was discovered in 2002 by an oilfield inspection crew working for

4543-429: The sea bed can result in artifacts becoming rapidly buried in sediments. These sediments then provide an anaerobic environment which protects from further degradation. Wet environments, whether on land in the form of peat bogs and wells, or underwater are particularly important for the survival of organic material, such as wood, leather, fabric and horn. Cold and absence of light also aid survival of artifacts, because there

4620-584: The sea, some wrecks have been examined in lakes. Most notable are Caligula 's pleasure barges in Lake Nemi , Italy . The Nemi ships and other shipwreck sites occasionally yield objects of unique artistic value. For instance, the Antikythera wreck contained a staggering collection of marble and bronze statues including the Antikythera Youth. Discovered in 1900 by Greek sponge divers, the ship probably sank in

4697-402: The security offered by their permanent positions allows a long-term commitment to excavation and publishing. Each professor holds an endowed fellowship, professorship, or chair Maritime archaeology Maritime archaeology (also known as marine archaeology ) is a discipline within archaeology as a whole that specifically studies human interaction with the sea, lakes and rivers through

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4774-753: The ship's identification as Two Brothers was announced by NOAA on February 11, 2011, the 188th anniversary of her sinking. The wreck is the first discovery of a wrecked Nantucket whaling ship. Nine historic trade ships carrying ceramics dating back to the 10th century until the 19th century were excavated under Swedish engineer Sten Sjöstrand in the South China Sea . In the Mediterranean area, maritime archaeologists have investigated several ancient cultures. Notable early Iron Age shipwrecks include two Phoenician ships of c. 750 BC that foundered off Gaza with cargoes of wine in amphoras . The crew of

4851-449: The shipping berths, has made working piers obsolete for the handling of general cargo, although some still survive for the handling of passenger ships or bulk cargos. One example, is in use in Progreso, Yucatán , where a pier extends more than 4 miles into the Gulf of Mexico , making it the longest pier in the world. The Progreso Pier supplies much of the peninsula with transportation for

4928-478: The ships of Emperor Caligula in Lake Nemi , Italy. Just a few decades later, in 1535, the 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

5005-502: The significantly increased sea traffic during the Roman era came a corresponding increase in shipwrecks. These wrecks and their cargo remains offer glimpses through time of the economy, culture, and politics of the ancient world. Particularly useful to archaeologists are studies of amphoras , the ceramic shipping containers used in the Mediterranean region from the 15th century BC through the Medieval period. In addition to many discoveries in

5082-405: The specialized skills of the underwater archaeologist . Others value an integrated approach, stressing that nautical activity has economic and social links to communities on land and that archaeology is archaeology no matter where the study is conducted. All that is required is the mastering of skills specific to the environment in which the work occurs. Before the industrial era, travel by water

5159-479: 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. As with archaeology as a whole, maritime archaeology can be practised within the historical, industrial, or prehistoric periods. An associated discipline, and again one that lies within archaeology itself,

5236-510: The term pier tends to have different nuances of meaning in different parts of the world. Thus in North America and Australia , where many ports were, until recently, built on the multiple pier model, the term tends to imply a current or former cargo-handling facility. In contrast, in Europe , where ports more often use basins and river-side quays than piers, the term is principally associated with

5313-452: The time the diver can spend in the water, and Surface-supplied diving equipment (SSDE or SSBA), which is safer but more expensive, and airline, or hookah equipment, a basic form of surface supplied equipment with limited depth applications. Both open circuit and rebreather scuba have been used, depending on which is best suited to the site. Relatively recent developments, mainly for special circumstances: The depth of sites can vary within

5390-491: The very factors that caused its survival in the first place, for example, when a covering of sediment has been removed by storms or the action of man. Active monitoring and deliberate protection may mitigate further rapid destruction making in situ preservation an option, but long-term survival can never be guaranteed. For very many sites, the costs are too great for either active measures to ensure in situ preservation or to provide for satisfactory conservation on recovery. Even

5467-610: The water's edge. Since the last ice age sea level has risen as much as 400 feet (120 m). Therefore, a great deal of the record of human activity throughout the Ice Age is now to be found under water. The flooding of the area now known as the Black Sea (when a land bridge, where the Bosporus is now, collapsed under the pressure of rising water in the Mediterranean Sea ) submerged

5544-409: The world, and sites such as Alexandria , Port Royal and Mary Rose now form important archaeological sites that are being protected, managed and conserved. As with shipwrecks, archaeological research can follow multiple themes, including evidence of the final catastrophe, the structures and landscape before the catastrophe and the culture and economy of which it formed a part. Unlike the wrecking of

5621-536: The wreck of the USS Monitor is near Cape Hatteras at 230 feet (70 m) depth at coordinates 35°0′6″N 75°24′23″W  /  35.00167°N 75.40639°W  / 35.00167; -75.40639 . When it was realised that recovering the whole vessel was not economically viable, work was done by saturation divers to recover the propeller, engine and turret. The Exosuit, a relatively lightweight and low powered Atmospheic diving suit intended for marine research.

5698-463: The wreck will over centuries completely deteriorate on the floor of the Atlantic Ocean . Comparative evidence shows that all iron and steel ships, especially those in a highly oxygenated environment, continue to degrade and will continue to do so until only their engines and other machinery project much above the sea-floor. Where it remains even after the passage of time, the iron or steel hull

5775-548: Was first used in 2014 at the Bluewater and Antikythera underwater research expeditions. Not all maritime sites are underwater. There are many structures at the margin of land and water that provide evidence of the human societies of the past. Some are deliberately created for access - such as bridges and walkways. Other structures remain from exploitation of resources, such as dams and fish traps. Nautical remains include early harbours and places where ships were built or repaired. At

5852-531: Was often easier than over land. As a result, marine channels, navigable rivers and sea crossings formed the trade routes of historic and ancient civilisations. For example, the Mediterranean Sea was known to the Romans as the inner sea because the Roman empire spread around its coasts. The historic record as well as the remains of harbours, ships and cargoes, testify to the volume of trade that crossed it. Later, nations with

5929-431: Was preserved). While the land surface is continuously reused by societies, the sea bed was largely inaccessible until the advent of submarines , scuba equipment and remotely operated underwater vehicles (ROVs) in the twentieth century. Salvagers have operated in much earlier times, but much of the material was beyond the reach of anyone. Thus Mary Rose was subject to salvage from the sixteenth century and later, but

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