Thermal history of the Mackenzie Plain, Northwest Territories, Canada: Insights from low-temperature thermochronology of the Devonian Imperial Formation

2019 ◽  
Vol 132 (3-4) ◽  
pp. 767-783 ◽  
Author(s):  
Jeremy W. Powell ◽  
Dale R. Issler ◽  
David A. Schneider ◽  
Karen M. Fallas ◽  
Daniel F. Stockli
Keyword(s):  
Low Temperature ◽  
Thermal History ◽  
Fission Track ◽  
Length Distribution ◽  
Sedimentary Basins ◽  
Track Length ◽  
Data Sets ◽  
Burial History ◽  
Cooling History ◽  
History Of

Abstract Devonian strata from the Mackenzie Plain, Northern Canadian Cordillera, have undergone two major burial and unroofing events since deposition, providing an excellent natural laboratory to assess the effects of protracted cooling history on low-temperature thermochronometers in sedimentary basins. Apatite and zircon (U-Th)/He (AHe, ZHe) and apatite fission track (AFT) thermochronology data were collected from seven samples across the Mackenzie Plain. AFT single grain ages from six samples span the Cambrian to Miocene with few Neoproterozoic dates. Although there are no correlations between Dpar and AFT date or track length distribution, a relationship exists between grain chemistry and age. We calculate the parameter rmr0 from apatite chemistry and distinguish up to three discrete kinetic populations per sample, with consistent Cambrian–Carboniferous, Triassic–Jurassic, Cretaceous, and Cenozoic pooled ages. Fifteen ZHe dates range from 415 ± 33 Ma to 40 ± 3 Ma, and AHe dates from 53 analyses vary from 225 ± 14 Ma to 3 ± 0.2 Ma. Whereas several samples exhibit correlations between date and radiation damage (eU), all samples demonstrate varying degrees of intra-sample date dispersion. We use chemistry-dependent fission track annealing kinetics to explain dispersion in both our AFT and AHe data sets and detail the thermal history of strata that have experienced a protracted cooling history through the uppermost crust. Thermal history modeling of AFT and AHe samples reveals that the Devonian strata across the Mackenzie Plain reached maximum burial temperatures (∼90 °C–190 °C) prior to Paleozoic to Mesozoic unroofing. Strata were reheated to lower temperatures in the Cretaceous to Paleogene (∼65 °C–110 °C), and have a protracted Cenozoic cooling history, with Paleogene and Neogene cooling pulses. This thermal information is compared with borehole organic thermal maturity profiles to assess the regional burial history. Ultimately, these data reflect the complications, and possibilities, of low-temperature thermochronology in sedimentary rocks where detrital variance results in a broad range of diffusion and annealing kinetics.

Resolving thermal histories via multi-kinetic apatite fission track data: A case study from Phanerozoic strata within the Peel Plateau NWT, Canada

2021 ◽  
Author(s):  
Jennifer Spalding ◽  
Jeremy Powell ◽  
David Schneider ◽  
Karen Fallas
Keyword(s):  
Low Temperature ◽  
Thermal History ◽  
Fission Track ◽  
Sedimentary Basins ◽  
Source Rocks ◽  
Apatite Fission Track ◽  
Petroleum Systems ◽  
History Of ◽  
Thermal Histories ◽  
Peel Plateau

<p>Resolving the thermal history of sedimentary basins through geological time is essential when evaluating the maturity of source rocks within petroleum systems. Traditional methods used to estimate maximum burial temperatures in prospective sedimentary basin such as and vitrinite reflectance (%Ro) are unable to constrain the timing and duration of thermal events. In comparison, low-temperature thermochronology methods, such as apatite fission track thermochronology (AFT), can resolve detailed thermal histories within a temperature range corresponding to oil and gas generation. In the Peel Plateau of the Northwest Territories, Canada, Phanerozoic sedimentary strata exhibit oil-stained outcrops, gas seeps, and bitumen occurrences. Presently, the timing of hydrocarbon maturation events are poorly constrained, as a regional unconformity at the base of Cretaceous foreland basin strata indicates that underlying Devonian source rocks may have undergone a burial and unroofing event prior to the Cretaceous. Published organic thermal maturity values from wells within the study area range from 1.59 and 2.46 %Ro for Devonian strata and 0.54 and 1.83 %Ro within Lower Cretaceous strata. Herein, we have resolved the thermal history of the Peel Plateau through multi-kinetic AFT thermochronology. Three samples from Upper Devonian, Lower Cretaceous and Upper Cretaceous strata have pooled AFT ages of 61.0 ± 5.1 Ma, 59.5 ± 5.2 and 101.6 ± 6.7 Ma, respectively, and corresponding U-Pb ages of 497.4 ± 17.5 Ma (MSWD: 7.4), 353.5 ± 13.5 Ma (MSWD: 3.1) and 261.2 ± 8.5 Ma (MSWD: 5.9). All AFT data fail the χ<sup>2</sup> test, suggesting AFT ages do not comprise a single statistically significant population, whereas U-Pb ages reflect the pre-depositional history of the samples and are likely from various provenances. Apatite chemistry is known to control the temperature and rates at which fission tracks undergo thermal annealing. The r<sub>mro</sub> parameter uses grain specific chemistry to predict apatite’s kinetic behaviour and is used to identify kinetic populations within samples. Grain chemistry was measured via electron microprobe analysis to derive r<sub>mro</sub> values and each sample was separated into two kinetic populations that pass the χ<sup>2</sup> test: a less retentive population with ages ranging from 49.3 ± 9.3 Ma to 36.4 ± 4.7 Ma, and a more retentive population with ages ranging from 157.7 ± 19 Ma to 103.3 ± 11.8 Ma, with r<sub>mr0</sub> benchmarks ranging from 0.79 and 0.82. Thermal history models reveal Devonian strata reached maximum burial temperatures (~165°C-185°C) prior to late Paleozoic to Mesozoic unroofing, and reheated to lower temperatures (~75°C-110°C) in the Late Cretaceous to Paleogene. Both Cretaceous samples record maximum burial temperatures (75°C-95°C) also during the Late Cretaceous to Paleogene. These new data indicate that Devonian source rocks matured prior to deposition of Cretaceous strata and that subsequent burial and heating during the Cretaceous to Paleogene was limited to the low-temperature threshold of the oil window. Integrating multi-kinetic AFT data with traditional methods in petroleum geosciences can help unravel complex thermal histories of sedimentary basins. Applying these methods elsewhere can improve the characterisation of petroleum systems.</p>

scholarly journals Preliminary report of fission track studies in the Jameson Land basin, East Greenland

1988 ◽  
Vol 140 ◽  
pp. 85-89
Author(s):  
K Hansen
Keyword(s):  
Low Temperature ◽  
Thermal History ◽  
Preliminary Report ◽  
Fission Track ◽  
Track Length ◽  
Terrigenous Material ◽  
East Greenland ◽  
Eastern Margin ◽  
Mountain Belt ◽  
History Of

Fission track (FT) analysis is especially suited to reveal and date low temperature events. The closure temperature of apatite (100 ± 30°C) and its annealing characteristics in the interval of 70-125°C are especially relevant to the study of the maturation of hydrocarbons (Gleadow et al., 1983). FT analyses were made on Permian to Cretaceous, quartzose sandstones and arkoses from the Jameson Land basin. Both FT ages and track length distributions for apatites were obtained for samples taken along the western and eastern margin of the basin (fig. land Table 1) in order to sttidy the tectonic and thermal history of the area. The investigation takes advantage of earlier FT work in the neighbouring Caledonian mountain belt which is believed to be the source of the terrigenous material, including the apatites, which make up the sediments (Hansen, 1985). A report of further Investigations in this area is in preparation.

Track length distribution and thermal history of apatites

1985 ◽  
Vol 10 (3) ◽  
pp. 406
Author(s):  
A. Chambaudet ◽  
M. Mars ◽  
M. Rebetez ◽  
M. Rossi
Keyword(s):  
Thermal History ◽  
Length Distribution ◽  
Track Length ◽  
History Of

scholarly journals Deconvolution of fission-track length distributions and its application to dating and separating pre- and post-depositional components

Geochronology ◽  
2021 ◽  
Vol 3 (2) ◽  
pp. 561-575
Author(s):  
Peter Klint Jensen ◽  
Kirsten Hansen
Keyword(s):  
Least Squares ◽  
Covariance Matrix ◽  
Thermal History ◽  
Prior Information ◽  
Fission Track ◽  
Length Distribution ◽  
Track Length ◽  
Fission Tracks ◽  
Apatite Crystals ◽  
Thermal Histories

Abstract. To enable the separation of pre- and postdepositional components of the length distribution of (partially annealed) horizontal confined fission tracks, the length distribution is corrected by deconvolution. Probabilistic least-squares inversion corrects natural track length histograms for observational biases, considering the variance in data, modelization, and prior information. The corrected histogram is validated by its variance–covariance matrix. It is considered that horizontal track data can exist with or without measurements of angles to the c axis. In the latter case, 3D histograms are introduced as an alternative to histograms of c-axis-projected track lengths. Thermal history modelling of samples is not necessary for the calculation of track age distributions of corrected tracks. In an example, the age equations are applied to apatites with predepositional (inherited) tracks in order to extract the postdepositional track length histogram. Fission tracks generated before deposition in detrital apatite crystals are mixed with post-depositional tracks. This complicates the calculation of the post-sedimentary thermal history, as the grains have experienced different thermal histories prior to deposition. Thereafter, the grains share a common thermal history. Thus, the extracted post-depositional histogram without inherited tracks may be used for thermal history calculation.

Thermal history of sedimentary basins by fission-track dating

1981 ◽  
Vol 5 (1-2) ◽  
pp. 235-237 ◽  
Author(s):  
N.D. Briggs ◽  
C.W. Naeser ◽  
T.H. McCulloh
Keyword(s):  
Thermal History ◽  
Fission Track ◽  
Sedimentary Basins ◽  
Fission Track Dating ◽  
History Of
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