The complex rifting and subsidence history stated earlier has generated a mixture of stratigraphy,

The complex rifting and subsidence history stated earlier has generated a mixture of stratigraphy,
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The complex rifting and subsidence history stated earlier has generated a mixture of stratigraphy,

Framework and timing conducive to hydrocarbon generation and entrapment (Bell and Campbell, 1990). To date, nevertheless, significant discoveries only have been situated within a few areas ( ag e.g. Hibernia, Terra Nova, Whiterose) of this northern Jeanne d’Arc basin. Main reservoirs can be found in belated Jurassic and Early Cretaceous superficial marine and fluvial sandstones deposited through the 2nd rift and postrift stages. Later Jurassic shales associated with the Egret member have a marine-rich supply that matured during subsequent burial in the Belated Cretaceous and Tertiary. Traps had been created because of the mid- Cretaceous from rollover anticlines ( ag e.g. Hibernia framework) and rotated fault obstructs, and additionally they had been mostly preserved through the subsequent Avalon uplift and erosion.

Figure 6. Seismic reflection profile 85-4 that is LEKeen and de Voogd, 1988), remigrated and coherency filtered by J. Hall and S. Deemer (individual interaction, 2001). Seismic perspectives identified are Au/A* (Oligocene and Top Cretaceous) and U (Tucholke et al., 1989). Basement crustal kinds are defined by characteristic alterations in representation pattern.

Many research has concentrated regarding the Jeanne d’Arc basin as well as other water that is shallow from the Banking institutions. Just several wells have actually been drilled in much deeper water. Nevertheless, the sediment circulation map (Figure 5a) reveals that significant thicknesses occur beneath many regions of the slope and rise bordering the Banking institutions ( e.g. Southern Whale, Salar, Carson-Bonnition, Flemish Pass and Orphan basins). Recently, extra seismic research has been undertaken in these much much deeper water basins to advance assess its financial potential. Past analysis for the much much deeper regions that are offshore made utilizing a couple of local seismic profiles gathered in the mid- 1980’s ( e.g. Keen and de Voogd, 1988; Tucholke et al., 1989). An even more current collection of local pages (Figure 5) now runs this protection throughout the Newfoundland that is northern basin. The much much deeper water an element of the profile that is LE85-4 shown in Figure 6 (J. Hall and S. Deemer, individual interaction, 2001) and a brief portion of the current Ewing2000-3 profile (Louden and Lau, 2002) throughout the Carson basin in Figure 7. A few tilted basement fault obstructs is seen as much as 100 km seaward through the rack break. The very first is a block that is large with a few sodium address that divides the overseas part associated with Carson-Bonnition basin into shallower and much deeper water parts. The deep-water area of thicker sediment and complex cellar framework may keep the potential that is best for hydrocarbons (Enachescu, 1992).

Figure 7. Reflection that is seismic Ewing 2000-3 across the exterior Carson-Bonnition basin showing cellar ridge with possible sodium that separates basin into internal (shallow) from outer (deep water) parts.

Seismic horizons identified are Au/A* and U, after Tucholke et al. (1989). Observe that these horizons pinch out and end against basement and cannot be traced into shallower water.

Further seaward of this faulted cellar, a 100-km wide area exists the place where a prominent reflector (U) masks the basement that is underlying. This reflector generally seems to terminate against a number of elevated basement highs. The A u _ A * reflector defines the Tertiary transition between flat-lying and bottom current dominated depositional sequences above the U-reflector. It is really not particular in the event that U-reflector is related to your Avalon unconformity associated with southern Banking institutions and/or the Early Cretaceous ?-reflector observed from the Scotian margin (Figure 4). The character regarding the basement that is relatively flat-lying this transitional area can be uncertain. Present drilling and seismic outcomes suggest the current presence of a wide area of serpentinized basement that is peridotite a conjugate establishing beneath the Iberia margin (Louden and Lau, 2002). A model that is similar formerly proposed by Enachescu (1992) for the Newfoundland basin. Feasible drilling objectives to resolve these problems have already been selected along Ewing that is profile 2000-2 the northern an element of the basin (Figure 8). A drilling leg of this Ocean Drilling Program is planned because of this work with July-Sept 2003.

Figure 8. Seismic expression profile and location of proposed Ocean Drilling Program drilling sites within the Newfoundland basin (Tucholke et al., 2002). Seismic perspectives Au and U are defined as per Figure 7. For basic location map start to see the Ocean Drilling Program internet site (http: //www-odp. Html)

Towards the northwest of Flemish Cap, an extremely wide area of dense sediment exists within Orphan basin.

This region experienced episodes that are rifting might have extended in to the belated Cretaceous. The majority of the basin is underlain by highly thinned continental crust but its deep water has precluded drilling activity that is much. The gravity highs linked to the rack side (Figure 5b) shows a difference that is significant gravity lows connected with a lot of the other basins. It has been modeled by changing the reduced crust with mantle, suggesting the current presence of a failed rift that had been abandoned whenever continental breakup shifted further towards the northeast (Chian et al., 2001). A rather dense series of Tertiary sediment into the much deeper water parts of Orphan basin suggests a predominance of post-rift as opposed to syn-rift subsidence (Keen and Dehler, 1993).