OFFSHORE PROJECTS

 

  In brief GeoCoastal Marine:

 

  • Is Australia's leading provider of marine coring for environmental assessment and have averaged more than 800-1,000 marine/coastal vibrocores per year in recent years.

 

  • Has the most powerful and sophisticated vibrocore sampling systems in Australia (our corers and methods are designed for chemical sampling, and have been used successfully by CSIRO to calibrate airborne EM results with pore water in cores of 28m with strong correlations).  

 

  • Has the only genuine continuous deep-vibrocoring capacity in the southern hemisphere utilising proprietary in-house developed ANCOR and PEP technology (i.e. does not require any supporting drill rig, or jackup platform). GeoCoastal have all world vibrocorer penetration records.

 

  • Has specialised vessel combinations designed specifically for different styles of investigation, are low-emissions, and have been regularly scrutinised for safety. Our vessels have $0.5 billion indemnity insurance for marine operations.

 

  • Has the most experienced marine operations personnel in Australia. During the late 1980's-early 1990's Prof. Graham was the Geological Operations Manager, and periodically Chief Scientist, on a deep-sea research vessel. He has designed many coring systems (gravity corer, piston corer, vibracorer, box-corer), and have taken long cores in greater than 4,000m water depth. He has conducted 8m length vibracoring in water depths to 275m with direct real-time electronic tilt and penetration measurement.

 

  • Has pneumatic percussion corers that are Australia's most powerful deployable seabed continuous coring equipment with over 500% more power than electric vibracorers - we have retrieved continuous stiff/very stiff clay seabed core of >7m.

Gladstone Harbour: Pre-Dredge Geochemical Assessment
The largest  seabed geochemical   assessment in Australia's history
(QCLNG for GPCL's EIS, 2009)

In 2009 GeoCoastal conducted all facets of the largest seabed geochemical assessment in Australi'a history. This included: ~700 marine percussion/ vibrocores to subseabed depth ranging to 18m utilising 3 vessels, sample processing for acid sulfate soil/contaminant assessment and administration in a village of 7 demountable buildings, commissioning laboratory analyses, QA/QC, safety, contaminant reporting and stratigraphic modelling (~12,000 page final report).

 

GeoCoastal's stratigraphic model was used digitally in the dredges by the main dredging contractors VODI, and GeoCoastal was retained for sediment monitoring services and advice by VODI throughout the dredging.

Moreton Bay Sand Resource Assessment: Brisbane Airport 2nd Runway Project
(Golder, 2005/2012)

GeoCoastal were commissioned to conduct two seabed coring assessments to establish a sand resource for the Brisbane Airport 2nd runway. 

 

The first survey was conducted in Dec 2005 with a total of 23 sites investigated to an average depth of 10.4m. Stratigraphic modelling identified 'coffee rock' and geochemical sampling identified one area of concern, that was later reconfirmed.

 

A second program was conducted in March 2012 where 25 sites were cored to an average of. 9.036 metres in single penetrations. Stratigraphic modelling was again conducted. This information formed the basis for the dredging tender.

Proposed Marina Development: 
Lauderdale, TAS
Contaminant, Acid Sulfate Soil, Geotechnical assessment
(Walker Corporation, 2008)

GeoCoastal were commissioned to carry out a geotechnical, contaminant & ASS assessment in the logistically difficult location of a tidal flat for a proposed canal/ marina development. There were a number of sensitive political and environ-mental issues attached to this project, and it was conducted in Winter in Tasmania. 

 

Percussion cores were taken at 33 sites to -9m sub-seabed in sediments ranging from very soft silt/fluid sands to several metres of stiff/very stiff/hard clays (as determined from geotechnical testing of the cores).

 

All aspects of contaminant assessment as well as stratigraphic modelling, were conducted by GeoCoastal including final reporting. Other aspects included press appearances, negotiation with protestors (who wrote a letter of commendation to the Tasmanian gov't about GeoCoastal's conduct), and expert witness appearances. 

Abbot Point:
Pre-dredge Sediment
Assessment
(GHD, 2008/2011)

GeoCoastal were commissioned twice to conduct seabed coring assessments for contaminant and acid sulfate soil assessment.

 

Interestingly, a previous consultancy group had used our bid in their winning tender then attempted a cheap option with a small vessel. We had done our homework on the exposure of this site and spoken to local tug masters.  Predictably, the result of using this underprepared contractor, was an expensive shambles. GeoCoastal were then recommissioned to finish the job.

 

  • In October 2008 GeoCoastal recovered 120 cores from 54 sites in conditions ranging to 20+knots with no standby.

  • Again in September 2011, we recovered 47 cores at 21 sites.