The geology and the prospectivity of the offshore Northeast Greenland have been investigated by a series of surveys financed by the public sector and by private companies.

Offshore geology

Source rock and reservoir

The lack of wells to tie the seismic interpretation, constrain the knowledge of the deposits in the basins offshore Northeast Greenland. None the less Hamann et al. (2005) argued for the presence of an almost complete post Caledonian succession, stretching from Devonian (maybe older) to present.

north_eastnorth_east_overview

To describe the main elements the following division, corresponding with the definition in Hamann et al. (2005) is used:

Koldewey platform
Structurel high, landward portion of the shelf.

Shannon High
Steep Basement Horst, delineated by normal faults active during the Mesozoic.

Danmarkshavn Basin
More than 13 km deep sedimentary basin in the south, shallows towards the north and has a fairly complete sedimentary succession from Devonian to recent is believed to be present. Salt diapirism occurs in the central part almost extending to the seafloor in the northern part. Cenozoic uplift, indicated by a Miocene unconformity.

Danmarkshavn Ridge
Northeast-Southwest trending series of westward dipping fault blocks 10-60 km wide with a main fault escarpment to the East towards the Thetis basin.

Thetis Basin
The Thetis Basin is believed to be a young basin with deposits of mainly Late Mesozoic (Cretaceous) and Cenozoic age.
 
Marginal High
A marginal high relief area forms the edge of the continental shelf in Northeast Greenland. The eastern margin of the high is characterized by seaward-dipping reflectors and pseudo-escarpments, and a single submarine volcano.

Steinmark1 Steinmark2

Onshore geology

The extensive sedimentary basin complex developed along the Northeast
Greenland Margin during Late Palaeozoic and the whole of the Mesozoic. The basin complex formed as a result of the breakup of the continental area that once encompassed both Greenland and Norway. A total of 6-7 km of sediment was deposited from the Carboniferous to the Cretaceous. Initial deposition in the basin complex was predominantly of non-marine sediments from rivers and lakes, but later the sea invaded the rift zone and marine sediments were deposited. A stratigraphically almost complete succession of Mid-Devonian to Cretaceous sediments is preserved between Scoresby Sund and Kuhn Ø.

Source rock and reservoir

table

The Jurassic development of Northeast Greenland is known to show a high degree of similarity with the western parts of the North Atlantic. The resemblance in development across the North Atlantic relates to the Northeast Greenland being conjugate margin with western Norway (Surlyk 2003).

Reservoirs and traps

The long term rifting of the margin might have provided several interesting, offshore syn-rift sand deposits. Hamann et al. (2005) argued, by analogy to the Norwegian shelf, for a sand prone middle Jurassic sequence as the primary reservoir target on the north-eastern Greenland shelf. Several other potential reservoirs have been pointed out: Upper Carboniferous fluvial sandstones, Upper Permian carbonates and deep marine sandstone turbidites and upper Jurassic and early Cretaceous sandstone deposits (Christiansen et al. 1992).

Oil seep in Germania Land

During fieldwork in 1990 oil seeps were found in Germania Land. The seeps were found in mineralised breccias in metamorphic basement, in connection with a NNW-SSE trending fault zone. Long-distance migration along the fault zone has been suggested. On the basis of geochemical analyses, a terrestrially derived source rock deposited in a lacustrine environment of Late Paleozoic age is likely (Christiansen et al. 1991).

oilpic1 olipic2

Conclusions Greenland Sea

  • The shelf area of Northeast Greenland is geologically similar to oil- and gas-producing basins offshore mid-Norway and on the Barents shelf.
  • There are many well-documented source rocks onshore, including the world class Upper Jurassic sediments that are the source of most North Sea and mid-Norwegian oil.
  • Onshore oil-seeps have been found on Germania Land, East Greenland. The most likeliy source rock seems to be of Late Palaeozoic age.
  • The sedimentary succession exposed in Northeast and East Greenland provide good models for reservoir sandstones and mudstone seals.
  • Despite a irregular seismic coverage some interesting large fault-block structures and salt diapirs have been observed.

References Greenland Sea

Christiansen, F.C., Bojesen-Koefoed, J., Jensen, S.M. & Stemmerik, L. 1991. Oil seep in basement, Germania Land, North-East Greenland. Geological Survey of Greenland. Open Files Series 91/7, 18 pp.

Christiansen, F.G., Dam, G., Piasecki, S. & Stemmerik, L. 1992. A review of Upper Palaeozoic and Mesozoic source rocks from onshore East Greenland. Special Publication of the European Association of Petroleum Geoscientists No. 2, 151-161.

Hamann, N. E., Whittaker, R. C. & Stemmerik, L. 2005. Geological development of the Northeast Greenland Shelf. Petroleum Geology: North-West Europe and Global Perspectives, 887–902.

Henriksen, N. 2008. Geological History of Greenland. Geological Survey of Denmark and Greenland. 272 pp.

Surlyk, F. 2003: The Jurassic of East Greenland: a sedimentary record of thermal subsidence, onset and culmination of rifting. Geological Survey of Denmark and Greenland Bulletin 1, 659-722.