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Welcome to the Underwater Archaeology Homepage from UnderwaterArchaeology.com! |
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Tools of the Trade Water-borne transportation allowed early civilizations to explore much of the globe, facilitated free trade, wars, and the rise and fall of mighty empires. Beneath the surface of our seas lies a physical record of humankind rich in artifacts from our past.
Scuba Diving Equipment In the past, free divers often made futile attempts at salvaging treasures from sunken ships and ancient cities by holding their breath, or diving from diving bells. But in 1952, with the invention of the world's first self-contained underwater breathing apparatus (SCUBA) by Jacques Cousteau, a new dimension of underwater exploration began. Refined today with the addition of enriched oxygen mixes (enriched oxygen in scuba tanks allows divers to stay down on the bottom for longer durations, with less risk of decompression sickness known as "the bends"), and rebreathers (these are systems that re-circulate oxygen mixes inside a closed system) divers can have the time necessary to map out, survey, and study the wreck sites of ancient ships and coastal cities buried in sediments. The scuba technologies of today allow archaeologists the time they need for the careful removal and preservation of artifacts. Underwater Cameras & Video Underwater Cameras and video are vital to archaeologists in the discovery and careful examination of shipwrecks and artifacts. When a discovery is made, it is important to map out and grid the entire area that is to be excavated. Video and photographic documentation is a big part of the process. When an artifact is discovered, it's exact location and orientation need to be carefully documented before it is carefully removed, and a visual record of anything that is to be removed is important before it is disturbed. Underwater Cameras come in a variety of shapes and sizes. All share the distinction of special underwater housings that are made to keep the camera dry, free of moisture and protected from underwater pressure. They also come with flash and lighting features which are used to illuminate objects and bring out colors which are normally not visible at depth. Underwater cameras can be carried by divers, or attached to Rov's to investigate anomalies in the deep ocean. Metal Detectors Metal Detectors are yet another modern innovation that allows researchers detailed study of a search area. Traditionally employed by vacationers combing beaches for treasures and coins buried in the sand, their are also models that are adapted for underwater use. Metal detectors consist of five main parts: the stabilizer, (which fits around a divers arm allowing a diver leverage in sweeping wide areas of sand), the control box, (which contains the circuits, microprocessor, batteries and controls), the shaft, (which is typically a rod that makes the metal detector adjustable for length), and the coil (also known as the search head or antennae, which actually senses the metal), and headphones. When small electrical currents pass through the coil of a metal detector, faint magnetic fields are generated around the head, pushing down into the sand. When the head passes over metal objects, it illuminates them with a faint magnetic field of their own, and emits a beeping signal to alert the diver. Metal detectors can be used to find everything from the nails that once held together a wooden hull, to coins, cannons, and bells, and they are vital in the careful study and mapping of a search area. Side Scan Sonar Side scan sonar is typically a device tethered like a mini-submersible to a ship by a cable, and then directed over large areas of the ocean floor. Mapping, or "mowing the lawn", as they affectionately refer to it, is a strategy employed by researchers sweeping an area for a suspected shipwreck. The sonar device emits fan-shaped pulses down toward the seafloor across a wide angle, and reports data back to the mother ship. The device may be towed from a surface vessel or submarine, or mounted on a ship's hull. The invention of side scan sonar has been instrumental in assisting researchers creating nautical charts, conducting surveys of the ocean floor, and especially in the finding and investigation of underwater objects such as shipwrecks. Remotely Operated Vehicles (ROV's) Remotely operated underwater vehicles (ROVs) are underwater robots tethered to ships and then sent down to explore the deep ocean. They are unmanned, and operated by a skilled technical crew from a control room in the vessel on the surface. The operators manuever them, receive video data, and control mechanical arms of the robot through signals sent through an umbilical cable. Recent advancements in underwater robotics have allowed researchers to discover wrecks that have been hidden away for hundreds of years, and sometimes centuries. The video images can be unforgettable. Few can forget, for example, their first glimpse of the images of the Titanic recorded beneath the headlights of ROV's Hercules and Argus. ROV's have been instrumental in the mapping, surveying, and collection of artifacts from several deep water shipwrecks, but in spite of the progress that they have made, there is still much work that needs to be done. There are vast areas of the ocean floor that have never been explored. Hiding their secrets in complete darkness in crushing depths well in excess of 3000 feet, it will be up to a new generation of ROV's to illuminate the secrets held there.
Rov's - Remotely Operated Vehicles Side Scan Sonar Enriched Air Nitrox Alvin and Successer
- deep sea submersibles
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Copyright 2006-2007 The Underwater Archaeology Homepage from UnderwaterArchaeology.com. Please note: this site does not claim endorsement for or by externally linked sites. |
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