Subsurface diagenetic evolution and porosity evaluation of Middle-Upper Devonian Kee Scarp reef, Norman Wells, Northwest Territories, Canada.
The Middle-Upper Devonian Kee Scarp Formation at Norman Wells consists of a carbonate platform and an overlying reefal buildup. Episodic increases in the rate of sea-level rise produced multiple cycles of reef growth, with a backstepping character. Reservoir porosity of these reefs is mostly represe...
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| Format: | Master Thesis |
| Language: | English |
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University of Windsor
1992
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| Online Access: | https://scholar.uwindsor.ca/etd/3664 https://scholar.uwindsor.ca/cgi/viewcontent.cgi?article=4663&context=etd |
| Summary: | The Middle-Upper Devonian Kee Scarp Formation at Norman Wells consists of a carbonate platform and an overlying reefal buildup. Episodic increases in the rate of sea-level rise produced multiple cycles of reef growth, with a backstepping character. Reservoir porosity of these reefs is mostly represented by micropores of various types developed during diagenesis by the action of aggrading neomorphism and dissolution. The microporosity was developed as intercrystalline microvoids within the present low-magnesium calcite (LMC) stromatoporoid, algal and matrix components. SEM studies show that microporosity development responded to neomorphism at various rates. Reef margins, grain shoals and lower, middle and upper foreslope facies have the highest and best developed microporosity compared to lagoon, reef flat and tidal flat facies. The micropores in Kee Scarp limestone can be classified into four categories based on their shapes: (1) stepwise rhombic, about 1$\mu$m to 2$\mu$m in diameter; mainly developed in stromatoporoids; (2) intercrystalline rhombic, about 1$\mu$m in diameter; mainly in algal aggregates; (3) microvugs, 4$\mu$m to 10 $\mu$m in diameter; mainly in algal aggregates; (4) microchannels, 12$\mu$m length and 0.5$\mu$m width; in algal aggregates and stromatoporoids. (Abstract shortened by UMI.)Dept. of Geology and Geological Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1992 .A958. Source: Masters Abstracts International, Volume: 31-04, page: 1695. Thesis (M.Sc.)--University of Windsor (Canada), 1992. |
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