Norway: Crustal Onshore-Offshore Project (COOP)Novatem Airborne Geophysics from Quebéc carried out the bulk of the detailed magnetic and radiometric measurements during the period 2010-2016. The coastal area between Kragerø and Brønnøysund has been covered with profiles having a flight altitude and line spacing of c. 60 and 250 m, respectively. Source: NGU

Norway: Crustal Onshore-Offshore Project (COOP)

Initially launched to study the onshore-offshore relationships along the coast of western Norway only, the Crustal Onshore-Offshore Project (COOP) has recently completed a Phase 3.

The Geological Survey of Norway (NGU) launched this project in 2010, with 8 sponsors and the objective to improve their knowledge of onshore-offshore tectonic links, deep weathering and heat flow along the coast of western Norway

More companies joined as late participants in 2011 and 2012, and the project was extended to a Phase II including the Møre margin, the Møre-Trøndelag Fault Complex and the Haltenbanken area. The project covers an area of approx. 120.000 km², with Froan, Møre, Viking, Stord, Egersund, Norwegian-Danish and Central basins. The COOP project includes acquisition of six airborne surveys and acquisition of gravity and heat-flow data.

The Geological Survey of Norway (NGU) holds complete gravity and aeromagnetic databases from the entire Norwegian mainland and offshore areas, in addition to detailed information on the mainland bedrock geology.

“Aeromagnetic and gravity data provide continuous coverage of the mainland and offshore areas and act as a bridge between areas traditionally investigated by two different methods: field bedrock mapping and seismic interpretation,” says Odleiv Olesen, project leader of COOP.

“High-resolution aeromagnetic surveys are particularly useful for detailed mapping of basement lithology and basement depth, igneous bodies, sand channels, salt diapirs, fault systems and deep weathering,” he adds.

The Coop Phase I Report was released last year and summarises the results from the Norwegian North Sea and western Norway. This report can be downloaded here:

Useful results

“In addition to expanding the Norwegian aeromagnetic and gravity database both onshore and offshore, the COOP project has delivered workflows for integration of seismic, well and outcrop data to improve our understanding of the emerging and overlooked plays on the shelf”, says Alastair Welbon, Geological Advisor in Neptune.

“The results included better models of crustal evolution and heatflow from the coast to the Continent Ocean Boundary and a step change in understanding weathered and fractured basement. The onshore analogues and structures can be linked to equivalent features offshore and are often a key discussion topic in play and prospect risk assessment,.” according to Welbon.

  The Coop project has provided valuable insight into the fractured basement play for Spirit Energy, in particular on the Frøya High which is a core area for us,” comments Spirit Energy’s Senior Geologist, Cecilie Hiorth.

She adds that developing onshore analogs to address critical issues related to fracture development and weathering processes offshore and the acquisition of new aeromagnetic data along with new 3D seismic data have brought the company a leap step forward in the understanding of the structural evolution of the Frøya High.

“Regular discussions and workshops with the researchers in NGU have been instrumental to integrate the research into our prospectivity evaluation,” she says.

Excursions to localities that represent analogues to offshore basement rocks have been an important part of the Coop activities. The Devonian sandstone on Ørlandet at the coast of Mid Norway was one of the interesting localities. Photo: NGU

Phase 4 in the pipeline

Phase 1 and 2 were financed by a total of 20 oil companies in addition to NGU, NPD, BKK and the state road company «Nye Veier», while Phase 3 covering the Frøya High and Mid Norway has been sponsored by 13 oil companies, Nye Veier, NPD and NGU.

The energy company “BKK” joined the consortium some years ago to achieve information on subsurface temperatures in the Bergen area. There is currently interest in the industry to extend the project northwards on the Trøndelag Platform, meaning there might also be a Phase 4 to this project.