The East Coast of Canada is usually divided in to three areas: the Nova Scotian margin when you look at the south, the Newfoundland margin at the heart and eastern, additionally the Labrador margin into the north (Figure 1). These margins formed in the past 200 million years once the supercontinent of Pangea rifted apart, first as North America separated from Africa after which because it separated from European countries and Greenland (Figure 2). These episodes of rifting thinned and heated the continental crust and lithosphere, which in turn subsided to make a complex pair of marginal basins. Considerable amounts of sediment have actually since accumulated within these basins and created sources and traps for hydrocarbon deposits. Exploration activity to locate and exploit these resources, mainly from seismic pages and boreholes associated with the previous three decades, has triggered the production that is present of off Newfoundland and gasoline off Nova Scotia. Exploration tasks of both commercial and clinical activities have additionally yielded a wealth of fundamental information that features significantly enhanced our comprehension of the basic procedures of lithospheric expansion and continental rifting that have actually created these margins and their hydrocarbon resources.
Figure 1. Map of Eastern Canada with areas of Nova Scotian, Newfoundland and Labrador margin that is continental. Dashed lines give locations of Appalachian front side (AF) and Grenville Front (GF), which divide the continental areas into three major geological provinces.
It’s the intent behind this paper that is brief summarize many of these findings.
I shall make use of recently available maps of total sediment thicknesses (Oakey and Stark, 1995) and gravity that is marine from satellite altimetry (Sandwell and Smith, 1997) to determine the many basins, plus some samples of local seismic pages to illustrate structures of both sediment and crust. The complex set of sedimentary basins and their underlying basement structures that form these continental margins extend over a very wide transitional region as clearly indicated by the maps and profiles. A sizable an element of the sediment that is thick exist within the deeper water slope and increase basins through this change area. New overseas research activity is currently focussing on these deep water basins. If significant accumulations of fuel and oil are observed, it might basically move the long term focus for the oil that is canadian gasoline industry from west to east. My hope is the fact that outcomes from all of these brand brand new endeavors, both commercial and systematic, could also continue steadily to play a essential part in increasing our fundamental knowledge of just just how these transitional regions kind.
Plate tectonic reconstructions regarding the North Atlantic area are constrained mainly by identifications of marine magnetic anomalies and major fracture areas that formed through the creation of ocean crust (Figure 2; Coffin et al., 1992). Such reconstructions may be used to figure out the ages and pre-drift roles of margin conjugates (in other terms. Continental parts which were when right beside one another before subsequent creation of intervening ocean crust). This is really important for determining the complete pattern of rifting by juxtaposition of crustal parts across both margin pairs. Needless to say, given that age and complexity of subsequent dish motions increases therefore will the doubt associated with the reconstructed roles.
Figure 2. Plate tectonic reconstructions during the opening regarding the North Atlantic Ocean at 180 Ma, 130 Ma, 80 Ma, and 50 Ma. Dashed lines give locations of chosen sea-floor distributing anomalies. NFZ=Newfoundland Fracture Zone; AFZ=Azores Fracture Zone; GFZ=Charlie-Gibbs Fracture Zone; BTJ=Biscay Triple Junction; DS=Davis Strait (from Coffin et al., 1992).
As defined because of the reconstructions, the separation of united states and Eurasia formed the North Atlantic margins in five phases, starting in the south and progressing into the north:
- North America separated from Africa to make the margin that is scotian before chron M29 (160 Ma).
- North America separated from Iberia to make the Newfoundland that is southern margin before chron M3 (125 Ma).
- The united states separated from European countries to create the Newfoundland that is northern margin after chron M0 (120 Ma).
- North America separated from Greenland to create the Labrador margin sometime before chron 31 (70 Ma).
- A stage that is final of divided Greenland from European countries starting fleetingly before chron 24 (55 Ma).