SVERDRUP BASIN, CANADIAN ARCTIC ARCHIPELAGO
THERMAL HISTORY RECONSTRUCTION BASED ON AFTA AND VR
AND IMPLICATIONS FOR HYDROCARBON PROSPECTIVITY
OUTLINE PROPOSAL - JANUARY 2009
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To provide new constraints on regional thermal
history in the Sverdrup Basin through analysis of new well samples
using apatite fission track analysis (AFTA) and vitrinite reflectance
(VR)
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To determine the timing of hydrocarbon maturation
and possible re-migration during the late Paleozoic Ellesmerian
and Tertiary Eurekan Orogenies.
Cost and availability:
This will be a non-exclusive study. A single company purchase will
be US$60,000.
Background:
Apatite fission track analysis of selected wells from the central
and western Sverdrup Basin undertaken for the Geological Survey of
Canada (GSC) by the Dalhousie University Fission Track Research Laboratory
in the 1990s provided a preliminary understanding of regional basin
thermal history trends. Additional well and outcrop samples from the
eastern Sverdrup Basin were analysed subsequently as part of a Canadian
Natural Sciences and Engineering Research Council Strategic Grant
to Dalhousie University (Arne et al. 1998, Can. J. Earth Sci., 35,
30-38 & 2002, Basin Research, 14, 183-205). New vitrinite reflectance
(VR) data were also obtained for both well and outcrop samples. Results
of these studies are dominated by Tertiary (Eurekan) cooling. Since
these early studies, significant advances have taken place in AFTA
technology, including a detailed understanding of the influence of
apatite composition on fission track annealing rates and the advent
of new methods for extracting thermal history information. In the
initial studies, thermal history modelling was limited to rapidly
cooled samples. However, a more sophisticated analysis of new data
from the central and western Sverdrup Basin will provide a detailed
thermal history framework for understanding the history of hydrocarbon
generation in the Sverdrup Basin. Possible outcomes include definition
of pre-Tertiary episodes, as well as possibly defining multiple episodes
of Tertiary cooling which could be of importance for understanding
re-migration of hydrocarbons.
Proposed work:
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Sampling of 8 new wells, at least four of which
will come from known hydrocarbon fields, for AFTA and VR. Final
selection of additional wells to sample will be undertaken in conjunction
with project sponsors, and is subject to approval by the National
Energy Board of Canada. Depending on interest, additional new wells
could be included.
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Reassessment of the regional thermal history
based on AFTA & VR data, and integration with existing organic
maturation and thermal maturity indicators from the GSC.
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Synthesis of thermal history results and regional
tectonic evolution, with discussion of the implications for hydrocarbon
prospectivity.
Deliverables & timeframe:
Results will be presented in a new Geotrack Report, with all data
presented in Appendices. Delivery of the final report will be end
of 2009.
Benefits:
The results of the study will allow mapping of the influence of variation
in source rock thermal histories on hydrocarbon prospectivity across
the Sverdrup Basin, allowing definition of more prospective areas
where peak source rock maturation occurred after formation of structures.
The thermal history solutions from AFTA and VR also provide rigorous
constraints for basin modelling, enabling more reliable and accurate
prediction of patterns of hydrocarbon occurrence (although this is
not included in this study).
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