Fécamp Geophysical

Client:

Eolien Maritime France (EMF)

Duration:

2 months

Budget:

NA

Project Date:

2013

Background

EMF (Eolien Maritime France) is an offshore windfarm developer and joint venture between EDF EN and DONG Energy. iXblue was awarded the geophysical investigation of the future offshore windfarm site off Fécamp, located in the English Channel, North of France.

Requirement

The scope of survey included multi-beam and sonar imagery full coverage, sub-bottom profiling of the top layer of sediment, geological magnetometry and ultra high resolution seismic to target the 50m penetration.

Challenges

  • The large area, approx.100Km², was subject to the high tidal stream and rough metocean conditions of the English Channel.
  • The resolution and accuracy of the acquired data had to comply with the specific requirements of the civil engineers and geophysicists working on the wind turbine installation.
  • All operations had to be adapted to the client’s strict and extensive survey planning schedule.

Survey Solution

  • To use the  ‘iXPlorer on a 24 hour basis because it can operate for 30 days without refuelling.
  • To maintain flexibility and efficiency by using inhouse equipment (except from the UHRS equipment) and have spares on board or ready to be shipped from the workshop.
  • To use synthetic aperture sonar SHADOWS to achieve a constant high resolution over a full swath (no gap at Nadir) and cope with the strong tidal current. This sonar fish is equipped with its own positioning system including fish motion sensor (FOG), INS and USBL transponder. It’s all embedded in a tough and heavy fish which can withstand heavy weather conditions.
  • To employ a multidisciplinary solution undertaking the full supervision of all tasks and partnering with a short list of dedicated specialists.

Outcome

We are pleased to report that this survey was completed on time, to standard and to budget, and the client EMF contracted iXblue to perform further surveys in following years.