| Title | A continuous thermal history for southern Baffin Island, Canada over the past 1.8 billion years: implications for the assembly of Rodinia and the rifting of Greenland |
| |
| Author | McDannell, K T ;
Schneider, D A; Currie, L D; Issler, D R; Zeitler, P K |
| Source | Thermo 2018: 16th International Conference on Thermochronology, conference abstracts; 2018 p. 135 |
| Links | Online - En ligne (complete volume - volume complet,
pdf, 9.72 MB)
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| Year | 2018 |
| Alt Series | Natural Resources Canada, Contribution Series 20180132 |
| Meeting | Thermo 2018 - 16th International Conference on Thermochronology; Quedlinburg; DE; September 16-21, 2018 |
| Document | book |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Nunavut |
| NTS | 15E; 15L; 51M; 16; 25E; 25F; 25G; 25H; 25I; 25J; 25K; 25L; 25M; 25N; 25O; 25P; 26; 27A; 27B; 35E; 35F; 35G; 35H; 35I; 35J; 35K; 35L; 35M; 35N; 35O; 35P; 36A; 36B; 36C; 36D; 36E; 36F; 36G; 36H; 36I; 36P;
37A |
| Area | Baffin Island; Hall Peninsula; Meta-Incognita Peninsula; Ungava Peninsula; Cumberland Peninsula; Foxe Basin; Hudson Strait; Cape Dyer |
| Lat/Long WENS | -80.0000 -60.0000 69.0000 61.0000 |
| Subjects | regional geology; tectonics; geochronology; thermal history; tectonic history; rifting; metamorphism; radiometric dating; uranium lead dating; argon argon dating; zircon dates; fission-track dates;
temperature; deposition; burial history; crustal uplift; convection; modelling; Archean; Rodinia; Canadian Shield; Trans-Hudson Orogeny; Hoare Bay Group; Pangaea; Chidliak Kimberlite Field; Grenville Orogeny; Farallon Plate; Phanerozoic; Mesozoic;
Cretaceous; Jurassic; Paleozoic; Devonian; Silurian; Ordovician; Cambrian; Precambrian; Proterozoic |
| Program | GEM2:
Geo-mapping for Energy and Minerals TransGEM |
| Released | 2018 09 01 |
| Abstract | New and recently published U-Pb, muscovite-biotite 40Ar/39Ar, K-feldspar MDD 40Ar/39Ar, zircon and apatite (UTh)/He, and apatite fission-track data were compiled and inverted for a comprehensive,
thermal history of southern Baffin Island, Canada. This work is a contribution to the Geo-mapping for Energy and Minerals (GEM) Baffin Island initiative and Trans-GEM synthesis of the Phanerozoic exhumation history of the Canadian Shield. Southern
Baffin Island is comprised of Archean plutonic basement metamorphosed during the Trans-Hudson Orogeny. Monazite UPb dating on the Hall Peninsula suggest peak metamorphic conditions were at ca. 1850-1820 Ma and remained at >550ºC ca. 100 My after the
thermal peak [1], while 40Ar/39Ar hydrous mineral ages and modeling suggest temperatures remained at >420-450ºC ca. 150-200 My after peak conditions [2]. New apatite U-Pb age populations are in agreement and range from 1674 ± 35 Ma to 1796 ± 75 Ma
(2?), suggesting elevated post-THO temperatures at ~450ºC. During the Meso- to Neoproterozoic the Hall Peninsula region experienced prolonged slow cooling on the order of ?0.5ºC/My until ca. 1000 Ma when cooling accelerated to ~1ºC/My due to
supercontinent Rodinia assembly. Sedimentary sequences place minimum timing constraints on basement rocks being at near-surface conditions in the early Paleozoic. Preliminary results from apatite fission-track data suggest that southwest Baffin
(Meta-Incognita and Hall Peninsula) was fully exhumed by Paleozoic time during basement uplift that likely exploited pre-existing, regional structures. Nearby Foxe Basin sediments suggest this region of the Canadian Shield was exhumed by the Late
Ordovician (ca. 450 Ma) and either remained topographically high, or experienced minor burial during subsequent continental-wide transgression and shallow marine carbonate deposition in the Silurian-Devonian. AFT data from a >1890 Ma volcanic tuff
cutting the Paleoproterozoic Hoare Bay Group sediments on the easternmost Cumberland Peninsula record rapid cooling in the Jurassic. The cooling signal recorded along Cumberland Peninsula is likely due to early crustal thinning related to rifting of
Greenland from mainland Canada during Pangaea breakup and aligns with a model of rift-flank uplift. AFT models are in agreement with ages of dike swarms in West Greenland given as evidence by [3] for the onset of rift extension. The summarized
cooling history of southern Baffin Island suggests post-THO cooling rates of ~1-3ºC/My from ca. 1700-1500 Ma, followed by slow cooling and Mesoproterozoic cooling pulses at ca. 1300 Ma and ca. 1000-950 Ma, likely due to Rodinia assembly. Rocks have
been at temperatures <100ºC since ca. 500 Ma. [1] Skipton et al., 2016, J. of Petrology, v.57(8); [2] Skipton et al., 2017, Lithos, v.284; [3] Larsen et al., 2009, J. Geol. Soc., v.166. |
| Summary | (Plain Language Summary, not published)
New and recently published U-Pb, muscovite-biotite 40Ar/39Ar, K-feldspar MDD 40Ar/39Ar, zircon and apatite (U-Th)/He, and apatite fission-track data were
compiled and inverted for a comprehensive, thermal history of southern Baffin Island, Canada. This work is a contribution to the Geo-mapping for Energy and Minerals (GEM) Baffin Island initiative and Trans-GEM synthesis of the Phanerozoic exhumation
history of the Canadian Shield. |
| GEOSCAN ID | 308424 |
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