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Petrological insights into thermal maturity, source rocks, migration, diagenesis. L.D. Stasiuk and N.S.F Wilson Natural Resources Canada Geological Survey of Canada. Thermal maturity – 2002-03 progress Reassess Vitrinite %Ro from Evenchick et al, 2002 (~ 160 samples).
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Petrological insights into thermal maturity, source rocks, migration, diagenesis L.D. Stasiuk and N.S.F Wilson Natural Resources Canada Geological Survey of Canada
Thermal maturity – 2002-03 progress • Reassess Vitrinite %Ro from Evenchick et al, 2002 (~ 160 samples). • New Vitrinite % Ro and Tmax from Rock Eval for about ~ 200 samples.
Petrology of Organic Matter and Rock Eval Evaluation of Potential Source Rocks • Osadetz et al. have defined ‘Effective Petroleum Systems’ in • Bowser Basin related to petroleum stains / shows proposed to come from: • a Paleozoic carbonate marine source rock deposited in a mesohaline to hypersaline setting (for stains in Muskaboo Creek Assemblage at Tsatia Mountain); • Mesozoic lacustrine – non-marine source rocks (for stains in Triangle zone) • Mesozoic normal marine source rock in Richie Well stains (e.g. 6745’) and in stains near Bucking Horse & Spatsizi River intersect.
Aptian to Albian to Campanian Tango Creek Formation; Non-marine potential hydrocarbon source rocks
Aptian to Albian to Campanian Tango Creek Formation: non-marine potential hydrocarbon source rocks in triangle zone Black shales (44/89, 872-875/92 series) : Bowser Basin: 1.34 - 2.54, 8.4 % TOC just North of Kitchener Lake. Sustut Basin 4.7 % TOC, near Stikine River-Cullivan Creek crossing for source rocks in the mid-late oil window (0.90 to 1.2 %Ro vitrinite). Coaly partings: 60-70 % TOC
Rock Eval pyrolysis for Tango Creek, Triangle Zone and Sustut Basin (for Rocks with vitrinite %Ro > 1.0 – 1.5 and Tmax > 450 C – i.e. late oil window to condensate - dry gas
Rock Eval pyrolysis for Tango Creek ?? for coals and black shales with vitrinite %Ro > 1.2-2.5 and Tmax > 480-560 C – i.e. condensate - dry gas
Terrestrial – cuticular organic matter in coals and shales Upper Jurassic to Upper Cretaceous deltaic deposits, Bowser and Sustut basins Tango Creek shales – 8 % Total Organic Carbon
Terrestrial – cuticular organic matter in coals and shales Upper Jurassic to Upper Cretaceous deltaic deposits, Bowser and Sustut basins
Aptian to Albian to Campanian Tango Creek Formation; Non-marine potential hydrocarbon source rocks – coals ? Vitrinite %Ro = 0.87
Aptian to Albian to Campanian Tango Creek Formation; Non-marine potential hydrocarbon source rocks – coals ? 875/92
Rock Eval pyrolysis for Skelhorne assemblage for coals and black shales with vitrinite %Ro of 2.6- 5.0 and Tmax > 600 oC – i.e. dry dry gas to sub-green schist
Recycled lacustrine Type I kerogen source rock clasts in Eagles Nest Assemblage (reworked from Muskaboo Creek ??)
Recycled lacustrine Type I kerogen source rock clasts in Eagles Nest Assemblage (reworked from Muskaboo Creek ??) Vitrinite %Ro 0.80-0.90. Fluorescent light White light
Recycled lacustrine Type I kerogen source rock clasts in Eagles Nest Assemblage showing Pediastrum like morphology (freshwater, e.g. lacustrine algae) Fluorescent light Modern
Some Pediastrum species also is characteristic of the littoral zone of oligotrophic waters
Crude oil generation from recycled lacustrine Type I kerogen source rock clasts in Eagles Nest Assemblage and migration of higher API oils in microfractures
High maturity recycled possible lacustrine Type I kerogen source rock clasts in Tango Creek, Eagles Nest and Todagin assemblage; Gas Zone, 1.0 to 1.4 %Ro
Recycled lacustrine Type I kerogen source rock clasts in Eagles Nest Assemblage (reworked from Muskaboo Creek ??) Evenchick et al., 2002 • Some Pediastrum species also characteristic of the littoral zone of oligotrophic waters
Pyrobitumen lining pores - dissolution - HC inclusions EP-91-91
Leached Pore space EP-91-91
Calcite cements Pyrobitumen + HC Inclusions Pore space – Fewer HC incs EP-91-91