Calecore’s multi-role DP2 survey vessel 'Highland Spirit' completes operations offshore Tunisia and Tanzania.
After completing a geotechnical investigation offshore Tunisia in December 2012 comprising a 50m composite borehole and 3 x 30m CPT’s in less than 3 days; preparations began for the Highland Spirit's transit south to Tanzania.
For the Gulf of Aden significant security assessments and preparations were made and the vessel arrived safely in Dar es Salaam on the 29th January where the Geophysical survey team joined the vessel and set sail for the survey area on 30th January, 2013.
The survey area had a complex seabed character and topography so before full acquisition commenced a reconnaissance survey was acquired to fully map seabed hazards and shallow waters across the area. Nine days later all geophysical and environmental acquisition had been completed over an extended site with full data processing on-going offshore.
A local Calecore and client team was based in country to allow ‘real-time’ data assessment, peer review and location planning supporting the offshore processing team. The vessel changed mode in Tanga where the geophysical team demobilised and the drilling and geotechnical engineering team joined the vessel and began preparations to start Phase 2 of the project ‒ geotechnical drilling.
Due to shallow geological and topographical challenges on site a number of spud locations were under review and so investigations for foundation and conductor driveability were required at multiple locations to allow flexibility in choosing the safest and most suitable location. The team onboard the Highland Spirit rose to the challenge of real time project planning and a relentless and challenging drilling programme; involving downhole CPT, push sampling and coring ‒ finally completing the programme after having drilled 20 holes, 450 cumulative metres in less than 8 days without incident despite the shallow water and intense programme.
The vessel now heads north for her next projects offshore Libya, Norway and the Russian Arctic.