| Title | The Lower Silurian Sayabec Formation in northern Gaspé: carbonate diagenesis and reservoir potential |
| Author | Lavoie, D; Chi, G |
| Source | Bulletin of Canadian Petroleum Geology vol. 49, no. 2, 2001 p. 282-298, https://doi.org/10.2113/49.2.282 |
| Year | 2001 |
| Alt Series | Geological Survey of Canada, Contribution Series 200089 |
| Publisher | GeoScienceWorld |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Quebec |
| NTS | 22A; 22B/01; 22B/08; 22B/09; 22B/16; 22G/01; 22G/08; 22H/01; 22H/02; 22H/03; 22H/04; 22H/05; 22H/06; 22H/07 |
| Area | Northern Gaspé; Gaspésie; Gaspé Peninsula; Ruisseau Isabelle; Lac Madeleine; Rivière Madeleine |
| Lat/Long WENS | -66.5000 -64.0000 49.5000 48.0000 |
| Subjects | fossil fuels; sedimentology; diagenesis; carbonates; reservoir rocks; porosity; hydrothermal alteration; fracturing; calcite; brine; meteoric waters; facies; limestones; dolomites; hydrocarbons;
nearshore environment; offshore areas; carbon isotopes; oxygen isotopes; stable isotope studies; fluid inclusions; petrographic analyses; depositional environment; dolomitization; stylolites; hydrocarbon migration; sea level changes; Lower Silurian;
Sayabec Formation; Northern Outcrop Belt; Salinic disturbance; Acadian Gaspé Belt; Appalachian Orogen; Salinic unconformity; post-Taconian; primary porosity; secondary porosity; fracture-filling cements; pore-filling cements; carbonate ramps;
dissolution; sediment infills; peritidal; neptunian dykes; microthermometry; Paleozoic; Silurian |
| Illustrations | geological sketch maps; stratigraphic columns; diagrams; tables; photomicrographs; photographs; plots; histograms; charts |
| Program | Appalachian Foreland and St. Lawrence Platform NATMAP Project |
| Abstract | The Lower Silurian Sayabec Formation represents a peritidal-dominated carbonate ramp that developed at the northern edge of the post-Taconian Gaspé successor basin. In the Late Silurian, during the
Salinic disturbance, the Sayabec ramp was subaerially exposed locally. This could have lead to the formation of economically significant secondary dissolution porosity. A detailed diagenetic study of the Sayabec Formation was carried out at selected
localities along the Northern Outcrop Belt in the Gaspé Peninsula, where the Salinic unconformity and hydrothermal alteration of the carbonate facies have been documented.
The diagenetic history consists of initial minor marine diagenesis (marine
cements in boundstones and neptunian dykes) followed by pervasive burial diagenesis that resulted in the emplacement of various pore- and fracture-filling calcite cements, due to the mixing of basinal brines and hydrothermal fluids. Late Silurian
tectonic exhumation of the lithifled carbonate ramp is recorded locally in meteoric-cement-filled fractures that were dissolution-enhanced after early burial. The significance of this event in generating porosity was relatively minor.
Preserved
porosity is observed where limestone facies and calcite cements were completely replaced by hydrothermal saddle dolomite. However, the porous dolostone is of geographically limited extent. The hydrothermal event is mostly recorded in high-temperature
calcite cements that occlude burial fractures. |
| GEOSCAN ID | 213511 |
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