GEOSCAN, résultats de la recherche


TitreA margin-wide BSR gas hydrate assessment: Canada's Atlantic margin
AuteurMosher, D C
SourceMarine and Petroleum Geology vol. 28, 2011 p. 1540-1553,
Séries alt.Secteur des sciences de la Terre, Contribution externe 20100265
ÉditeurElsevier BV
Documentpublication en série
Mediapapier; en ligne; numérique
ProvinceRégion extracotière de l'est
Lat/Long OENS -65.0000 -45.0000 56.0000 44.0000
Sujetshydrocarbures; hydrate; méthane; capacité de production d'hydrocarbures; levés géophysiques; levés de reflexion sismiques; marges continentales, atlantique; plate-forme continentale; talus continental; géologie du substratum rocheux; roches sédimentaires; analyses structurales; caractéristiques structurales; failles; exploration; exploration pétrolière; sédiments marins; dépôts glaciaires; dépôts postglaciaires; levés sismiques; levés de reflexion sismiques; hydrates de gaz; combustibles fossiles; géophysique; géologie marine; Phanérozoïque; Cénozoïque; Mésozoïque
Illustrationslocation maps; graphs; profiles
ProgrammeHydrates de gaz, Évaluation des Hydrates de gaz
Résumé(disponible en anglais seulement)
It is the intent of this paper to explore a significant extent of an entire passive continental margin for hydrate occurrence to understand hydrate modes of occurrence, preferred geologic settings and estimate potential volumes of methane. The presence of gas hydrates offshore of eastern Canada has long been inferred from estimated stability zone calculations, but little physical evidence has been offered. An extensive set of 2-D and 3-D, single and multi-channel seismic reflection data comprising in excess of 140,000 line-km was analyzed. Bottom simulating reflections (BSR) were unequivocally identified at seven sites, ranging between 250 and 445 m below the seafloor and in water depths of 620 - 2850 m. The combined area of the BSRs is 9311 km2, which comprises a small proportion of the entire theoretical stability zone along the Canadian Atlantic margin (~715,165 km2). The BSR within at least six of these sites lies in a sedimentary drift deposit or sediment wave field, indicating the likelihood of grain sorting and potential porosity and permeability (reservoir) development. Although there are a variety of conditions required to generate and recognize a BSR, one might assume that these sites offer the most potential for highest hydrate concentration and exploitation. Total hydrate in formation at the sites of recognized BSR's is estimated at 17 to 190 x 109 m3 or 0.28 to 3.12 x 1013 m3 of methane gas at STP. Although it has been shown that hydrate can exist without a BSR, the results from this regional study argue that conservative estimates of the global reserve of hydrate along continental margins are necessary.