Traditionally, in archaeology the site is divided into 1 m by 1 m squares with the aid of ropes and cables.
This system enables us to easily provide each object with a set of coordinates.
As the position of the main vessel and receiver unit are precisely known from DGPS, the geographic location of the pinger can be calculated.
It is possible to use several pingers at the same time.
Franck Goddio has developed a special system approach according to which every archaeological campaign is performed.
The work begins with the study and critical review of archives and/or ancient texts, in order to determine and characterize probable locations of archaeological vestiges.
The GPS (Global Positioning System) is an absolute geographical positioning system that can provide the position in latitude, longitude and altitude of the mobile receiver, anywhere on the earth through information sent by a constellation of satellites.
Capable of diving to a depth of 1,000 metres and carrying one passenger and one pilot, they were fitted with a camera and powerful searchlights.Nuclear Magnetic Resonance (NMR) Magnetometers are the principal sensors in the surveying system.These highly sensitive instruments were developed by the French Atomic Energy Commission (CEA).Afterwards, conservation and the cataloging of findings by specialists are implemented.Analysis of findings are then performed by experts who also participate in the publication of scientific results.In underwater archaeology a baseline is first set out and firmly anchored to the seabed.Secondary lines can then be run at 90 degrees to the main baseline to create the grid.With the help of non-intrusive cutting edge technology, such as a specially developed nuclear magnetic resonance magnetometer (NMR), multi-beam bathymetry, sidescan sonar, sub-bottom profiler and satellite positioning system (DGPS) the site is mapped.Test excavations are then performed in order to characterize specific features seen on the electronic maps.By juxtaposing geographically positioned bands of sonar information a complete coverage of the surveyed area can be created.The water dredge is an underwater suction device that is used in excavation underwater to remove sediment.