NEcosse

Potential Source-Rocks

Base of Continental Margin

The seismic lines of the Nova Scotia deep offshore (Canada), like this Canvas autotrace, suggest that the only possible generating petroleum sub-system (source-rock interval) is at the base of the margin (above the breakup unconformity), immediately, below the salt interval. Although it is not very obvious, it is possible that between the oceanic crust and the evaporites a hyper-saline lacustrine sedimentary series was deposited, as is the case in the eastern Brazil offshore. However, at the moment, such a source-rock interval is, purely, speculative. The data, below the salt is very difficult to pick coherent seismic horizons. On the other hand, the organic matter of the potential organic rich marine intervals associated with the Cretaceous marine transgression is, most likely, immature. Their burial is insufficient, since the water column does not play any role in the maturation of the organic matter.