GEOSCAN, résultats de la recherche

Menu GEOSCAN


TitreWestern Davis Strait, a volcanic transform margin with petroliferous features
AuteurJauer, C D; Oakey, G N; Li, Q
SourceMarine and Petroleum Geology vol. 107, 2019 p. 59-80, https://doi.org/10.1016/j.marpetgeo.2019.05.004
Année2019
Séries alt.Ressources naturelles Canada, Contribution externe 20180146
ÉditeurElsevier BV
Documentpublication en série
Lang.anglais
DOIhttps://doi.org/10.1016/j.marpetgeo.2019.05.004
Mediapapier; en ligne; numérique
Formatspdf (Adobe® Reader®); html
ProvinceNunavut; Région extracotière du nord
SNRC15; 16; 25A; 25H; 25I; 26P; 27A
Lat/Long OENS -65.0000 -57.0000 68.5000 60.0000
Sujetsbassins sédimentaires; ressources pétrolières; hydrocarbures; capacité de production d'hydrocarbures; présence de pétrole; nappes de pétrole; dégagements gazeux; méthane; roches mères; maturation thermique; géologie du substratum rocheux; géologie du socle; caractéristiques structurales; zones de failles; failles; failles, extension; failles, chevauchement; failles transformantes; fosses d'effondrement; zones de fracture; lithologie; roches ignées; roches volcaniques; basaltes; roches intrusives; roches sédimentaires; interprétations géophysiques; interpretations sismiques; interprétations de la pesanteur; anomalies gravimétriques; gravité de bouguer; interprétations magnétiques; anomalies magnétiques; diagraphie géophysique; cadre tectonique; antécédents tectoniques; magmatisme; volcanisme; décrochement horizontal; crevasses; marges plaques; intrusions; filons-couches; expansion océanique; croûte océanique; croûte continentale; analyses structurales; échantillons carrotés; échantillonnage par drague; télédétection; imagerie par satellite; méthodes radar; puits d'exploration; Paléogène; Eocene; Paléocène; Bassin de Saglek ; géologie marine; géologie structurale; tectonique; combustibles fossiles; géophysique; Phanérozoïque; Cénozoïque; Tertiaire; Mésozoïque; Crétacé; Paléozoïque
Illustrationslocation maps; geoscientific sketch maps; profiles; seismic profiles; stratigraphic charts; geophysical logs; seismograms; cross-sections; schematic representations
ProgrammeSystèmes pétroliers de Baffin, GEM2 : La géocartographie de l'énergie et des minéraux
Diffusé2019 05 11
Résumé(disponible en anglais seulement)
We present a compilation of the western Davis Strait region offshore southeastern Baffin Island, Nunavut, Canada with new subsurface geological structural details and observations regarding past hydrocarbon occurrences from scientific and commercial exploration.
This consists of seismic mapping with archival data correlated with a filtered marine Bouguer anomaly gravity compilation and magnetic data sets covering northern Saglek Basin, the western part of the Lady Franklin Basin and the Ungava Fault Zone from south of Baffin Bay.
A regional seismic horizon for mapping basin architecture comes from the top of the Paleogene volcanic syn-magmatic zone, where pervasive volcanic flows and intrusions are intermingled with the sedimentary section. The seismic depth map to the top of the regional volcanic seismic horizon shows pre-rift sedimentary basins having maximum depths of approximately 4-5 km flanking the shallower Ungava Fault Zone. Correlation of Bouguer anomaly gravity and magnetic data interpretations with the seismic mapping, indicate that over some areas true crystalline basement is deeper than can be determined by reflection seismic, as the base of the syn-magmatic section is not resolvable for seismic mapping.
Extensive Paleogene mafic intrusives and extrusive basalts dominate the architecture of this volcanic rifted margin as seen by the dominant high amplitude magnetic anomalies associated with many deeper structures. The over 250 km long Davis Strait Fault is recognised as the key structural element of the Ungava Fault Zone (UFZ) and valley complex. The adjoining Davis Strait High maps on seismic as a continuous structure running the length of Davis Strait plunging southwards to a Bouguer gravity high feature that terminates the western end of the extinct Eocene spreading zone south of Davis Strait. This horn shaped structural feature establishes the presence of an accommodation zone with multiple faults and localised thrust faulting as required to fit the complex mechanics for strike-slip motion that occurs along the south end of this transform fault system. The revised marine Bouguer anomaly gravity data set also defines two new, near shore grabens east of Cumberland Sound, the southern Tariut Basin and the northern Imaqpik Basin, each extending over 100 km in length with sediment thicknesses of at least 4 km. These pre-rift basins most likely originate from the Paleozoic based on seafloor dredge and nearby shallow drill cores from previous studies. The hydrocarbon charge of a previously unexplained petroliferous shallow marine drill core that is adjacent the eastern edge of the Tariut Basin is attributed to Paleozoic source rocks that have undergone enhanced thermal maturation from sill intrusion associated with rifting. The Imaqpik Basin shows strong evidence of a hydrocarbon system from the proximity of clustered interpreted sea surface oil slicks, mapped from satellite radar images, and a local zone of anomalously high dissolved methane measured within the water column that originates from the seafloor immediately east of Cape Dyer at the northern limit of that basin. The overlying Cape Dyer flood basalt field extends from limited onshore exposures into the offshore and maps with magnetic data over an area of approximately 13,000 km2. This extrusive feature and it's implicit underlying intrusive components are likely the unconventional heat source for the anomalous enhanced thermal maturation of Paleozoic to Paleogene source rocks in these pre-rift basins that host this previously unrecognised petroleum system.
Résumé(Résumé en langage clair et simple, non publié)
La géologie marine du côté ouest du détroit de Davis, au large de l'île de Baffin, au Nunavut, a fait l'objet d'études sporadiques au cours des 50 dernières années. Cette synthèse de bureau des anciennes données qui a été de nouveau examinée montre à présent qu'il existe deux nouveaux bassins extracôtiers présentant un potentiel pour des ressources pétrolières. Ces bassins justifient l'observation par satellite et par bateau de nappes d'hydrocarbures naturellement présentes, formées par les fuites d'hydrocarbures du fond marin. Cette étude complète et élargit les travaux plus étendus effectués par le Danemark sur le côté est du détroit de Davis.
GEOSCAN ID308456