Made by ckw
© 2008 oceanDTM
Most of the 2500 users are commercial fishing vessels. There are however an increasing number of scientific and research groups putting the software to novel use. These include the British
Geological Survey Oceanlab at the University of Aberdeen both of which use the full multibeam capability of the system.
The Norwegian company Olex AS produces an electronic chart system which, in addition to navigational tasks, also maps the seabed by means of the ship's echosounder and GPS. An Olex user may contribute his own seabed data to Olex AS. The company adds the data to the database and in return gives the user an updated copy. Several hundred users have over the last 8 years contributed some 2 billion soundings.
The database organizes the world as 5x5 meter cells. Vertical resolution is 1 meter in deep areas, 0.1 meter at depths less than 100 meters. Horizontal datum is WGS84; vertical reference is equinoctial spring low water.
Positional quality is generally better than 10 meters. Degradations are usually due
to GPS installation issues like wrong chart datum or missing instrument offsets.
Occasional positional jitter is detected and rejected in real-
The simplistic echosounders found onboard fishing vessels uses a fixed value of water
sound speed, usually between 1470 to 1530 meter per second; the database harmonizes
all contributions to 1500 meter per second. This means that relative depths are highly
accurate and repeatable between various contributors, though absolute depth may be
1-
Free bathymetry data? If you have any large bathymetric datasets that you think might be suitable for adding to the Olex database please contact us.
F
For prices for the various Olex modules see here.