|Title||Organic petrology and thermal maturity of the Upper Ordovician Utica Shale, southern Quebec, Canada|
|Author||Haeri Ardakani, O; Sanei, H S; Lavoie, D L|
|Source||The 31st Annual Meeting of the Society for Organic Petrology, abstracts; 31, (2014), 2014 p. 1-2|
|Alt Series||Earth Sciences Sector, Contribution Series 20140104|
|Publisher||The Society for Organic Petrology|
|Meeting||The 31st Annual Meeting of the Society for Organic Petrology; Sydney; AU; September 27 - October 3, 2014|
|Media||paper; on-line; digital|
|NTS||21L; 31H; 31I|
|Area||St. Lawrence Platform|
|Lat/Long WENS|| -75.0000 -71.0000 46.7500 45.0000|
|Subjects||fossil fuels; hydrocarbons; hydrocarbon potential; petroleum; petroleum provinces; petroleum exploration; petroleum generation; petroleum occurrence; petroleum resources; oil shales; oil; Utica
|Illustrations||location maps; stratigraphic columns; photographs; plots|
|Program||Shale Reservoir Characterization, Geoscience for New Energy Supply (GNES)|
|Abstract||The present study focused on results of Rock-Eval analysis and organic petrology of Utica Shale cores from three wells in the southern Quebec (Fig. 1) at three different depths. Deep, intermediate and
shallow Uica samples are from Talisman Saint-Edouard #1 (1997 to 2030 m), Junex Becancour #8 (700 to 752 m), and Junex Saint-Augustin #1 (351 to 514 m), respectively (Fig. 2). |
The Upper Ordovician deep-marine, thick clastic succession of Utica
Shale in southern Quebec overlies the predominantly shallow marine carbonate facies of the Cambrian-Ordovician St. Lawrence Platform (Fig. 1). The calcareous shales of the Utica Shale started to accumulate in a poorly oxygenated setting due to rapid
increase of relative sea level rise. The Utica Shale is progressively thicker and deeper from NW to SE and is also remobilized and imbricated in thrust stacks beneath the St. Lawrence Platform (Fig. 2).
Samples have generally fair to good present
median TOC content of ranging from 0.7 to 1.3%. The major organic matter constituents are matrix and migrated bitumen and pyrobitumen, chitinozoan, and graptolite that observed in intermediate Utica samples. The reflectance has been measured on
matrix and solid bitumen and chitinozoan and graptolites. There is a strong agreement between bitumen reflectance and chitinozoan reflectance when they are converted to vitrinite reflectance using equations of Bertrand (1990) and Bertrand and Malo
The results show that the samples from the deeper parts of Utica Shale have equivalent VReqv of 2.12% and are in the dry gas zone while intermediate and shallow Utica samples have VReqv of 1.17% and 1.24%, at the end of oil
window and the onset of et gas zone, respectively. This is in agreement with Rock-Eval data. VRo variations within the samples are caused by the nature of bitumen accumulation, matrix bitumen often shows lower maturity than the solid accumulated
bitumen mostly due to surface quality of the measured area.
Random reflectance (VRo) measurement is shown to be a robust method for indicating the thermal maturity of samples with fine dispersed organic matter particles. Recent improvements in
petrographic analysis allow accurate reflectance measurements on nano-scale spots, providing reliable information on thermal maturity.
|Summary||(Plain Language Summary, not published)|
The present study used cores from three wells in the southern Quebec to evaluate the level of thermal maturity of Utica Shale in this area.