TY - GEN
T1 - Oil seepage onshore West Greenland
T2 - Evidence of multiple source rocks and oil mixing
AU - Bojesen-Koefoed, J.A.
AU - Christiansen, F.G.
AU - Peter Nytoft, H.
AU - Pedersen, A.K.
PY - 1999
Y1 - 1999
N2 - Widespread oil seepage and staining are observed in lavas and hyaloclastites in the lower part of the volcanic succession on northwestern Disko and western Nuussuaq, central West Greenland. Chemical analyses suggest the existence of several petroleum systems in the underlying Cretaceous and Paleocene fluvio-deltaic to marine sediments. Seepage and staining commonly occur within vesicular lava flow tops, and are often associated with mineral veins (mostly carbonates) in major fracture systems. Organic geochemical analyses suggest the existence of at least five distinct oil types: (1) a waxy oil which, on the basis of the presence of abundant angiosperm biological markers, is interpreted as generated from Paleocene mudstones (the 'Marraat type'); (2) a waxy oil, probably generated from coals and shales of the Cretaceous Atane Formation (the 'Kuugannguaq type'); (3) a low to moderately waxy oil containing 28,30-bisnorhopane, and abundant C27-diasteranes and regular steranes (the 'Itilli type'), possibly generated from presently unknown Cenomanian-Turonian marine mudstones; (4) a low wax oil of marine, possibly lagoonal/saline lacustrine origin, containing ring-A methylated steranes and a previously unknown series of extended 28-norhopanes (the 'Eqalulik type'); (5) a waxy oil with biological marker characteristics different from both the Kuugannguaq and Marraat oil types (the 'Niaqornaarsuk type'), probably generated from Campanian mudstones. The presence of widespread seepage and staining originating from several source rocks is encouraging for exploration in basins both on- and offshore western Greenland, where the existence of prolific source rocks has previously been the main exploration risk.
AB - Widespread oil seepage and staining are observed in lavas and hyaloclastites in the lower part of the volcanic succession on northwestern Disko and western Nuussuaq, central West Greenland. Chemical analyses suggest the existence of several petroleum systems in the underlying Cretaceous and Paleocene fluvio-deltaic to marine sediments. Seepage and staining commonly occur within vesicular lava flow tops, and are often associated with mineral veins (mostly carbonates) in major fracture systems. Organic geochemical analyses suggest the existence of at least five distinct oil types: (1) a waxy oil which, on the basis of the presence of abundant angiosperm biological markers, is interpreted as generated from Paleocene mudstones (the 'Marraat type'); (2) a waxy oil, probably generated from coals and shales of the Cretaceous Atane Formation (the 'Kuugannguaq type'); (3) a low to moderately waxy oil containing 28,30-bisnorhopane, and abundant C27-diasteranes and regular steranes (the 'Itilli type'), possibly generated from presently unknown Cenomanian-Turonian marine mudstones; (4) a low wax oil of marine, possibly lagoonal/saline lacustrine origin, containing ring-A methylated steranes and a previously unknown series of extended 28-norhopanes (the 'Eqalulik type'); (5) a waxy oil with biological marker characteristics different from both the Kuugannguaq and Marraat oil types (the 'Niaqornaarsuk type'), probably generated from Campanian mudstones. The presence of widespread seepage and staining originating from several source rocks is encouraging for exploration in basins both on- and offshore western Greenland, where the existence of prolific source rocks has previously been the main exploration risk.
UR - http://www.scopus.com/inward/record.url?scp=80052537630&partnerID=8YFLogxK
U2 - 10.1144/0050305
DO - 10.1144/0050305
M3 - Conference article in proceedings
AN - SCOPUS:80052537630
SN - 1-86239-039-8
VL - 1
T3 - Petroleum Geology Conference series
SP - 305
EP - 314
BT - Petroleum geology of northwest Europe: Proceedings of the 5th Conference
A2 - Fleet, A.J.
A2 - Boldy, S.A.R.
PB - Geological Society of London
ER -
