Blog Post Details

GISCO (Gulf Industrial Services Company) in October 2023 to carry out a Geophysical Seabed Survey.

The objective was to survey the 450x100 jetty area of IMI (International Maritime Industry) - a subsidiary of Saudi Aramco, Al khair Kingdom of Saudi Arabia to accommodate a drilling demonstration using a jackup rig. To also identify the topography and character of the Seabed using a Sub Bottom Profiler.
The survey started with the calibration of hemisphere DGPS antenna using known point at TRENCHMARK office in Nigeria. Further azimuth test was done on board using the vessel line of site. A tab test was done on the sub bottom profiler to see Seabed reflections. I deployed the following equipment during the survey and post processing of data:
*Edgetech 424 Sub Bottom Profiler unit and Towfish 
* Hemisphere DGPS
* Eiva Navipac 4D
*Sonarwiz 6.0
*MicroStation.
To exceed our client's expectations we did the following:
1 We deployed a navigation system using Eiva Navipac in a word geodetic parameter (WGS 84) zone 39 at UTM North.
2 Hemisphere DGPS was side mounted on the port side of the vessel in linear direction to the tow point of the SBP
3. SBP was towed at 4.5m on the port of the vessel
4. DGPS position was output from Eiva Navipac PC to the SBP acquisition Computer 
5. A trial survey line was ran longitudinal to the jetty to compare coverage
6. All surface and subsurface features were taking note with the position during survey 
7. Upon completion of field acquisition I used sonarwiz to apply geodetic correction on the data, TVG was applied to compensate for weak Sonar signals, digitize contact and feature analysis.
It was a memorable exercise in the harsh atmosphere of the Parisian Gulf