Browsing Earth and Environmental Sciences by Author "Yakymchuk, Chris"
Now showing items 1-11 of 11
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Anatexis of former arc magmatic rocks during oceanic subduction: A case study from the North Wulan gneiss complex
Li, Xiucai; Niu, Manlan; Yakymchuk, Chris; Yan, Zhen; Fu, Changlei; Zhao, Qiqi (Elsevier, 2018-09-01)Migmatites are widespread in the North Wulan gneiss complex from the South Qilian–North Qaidam orogenic belt, but their petrogenesis and ages are poorly constrained. Here, an integrated study of petrography, whole-rock ... -
Behaviour of apatite during partial melting of metapelites and consequences for prograde suprasolidus monazite growth
Yakymchuk, Chris (Elsevier, 2017-03-01)The suprasolidus behaviour of apatite and monazite is examined for an average metapelite composition using phase equilibria modelling coupled with solubility equations of these minerals. Both closed- and open-system scenarios ... -
Contrasting accessory mineral behavior in minimum-temperature melts: Empirical constraints from the Himalayan metamorphic core
Cottle, John M.; Larson, Kyle P.; Yakymchuk, Chris (Elsevier, 2018-07-01)Medium-grained leucogranite in the Tama Kosi region of the Nepalese Himalayan Metamorphic Core yields a relatively narrow range of monazite 208Pb/232Th dates with a dominant population at ~21.0 Ma inferred to represent ... -
Corundum formation by metasomatic reactions in Archean metapelite, SW Greenland: Exploration vectors for ruby deposits within high-grade greenstone belts
Yakymchuk, Chris; Szilas, Kristoffer (Elsevier, 2018-05-01)Corundum (ruby-sapphire) is known to have formed in situ within Archean metamorphic rocks at several localities in the North Atlantic Craton of Greenland. Here we present two case studies for such occurrences: (1) Maniitsoq ... -
Fluid-present anatexis of Neoarchean tonalite and amphibolite in the Western Shandong Province
Yakymchuk, Chris; Zhao, Wenran; Wan, Yusheng; Lin, Shoufa; Longstaffe, Fred (Elsevier, 2019-02)Metatonalite and amphibolite from the Taishan region of the Western Shandong Province in the North China Craton record c. 2.60 Ga fluid-present partial melting via the breakdown of biotite, plagioclase and quartz to produce ... -
From Source to Sink: Petrogenesis of Cretaceous Anatectic Granites from the Fosdick Migmatite-Granite Complex, West Antarctica
Brown, Caitlin R; Yakymchuk, Chris; Brown, Michael; Fanning, Christopher Mark; Korhonen, Fawna J.; Piccoli, Philip M.; Siddoway, Christine S. (Oxford University Press, 2016-07-01)Anatectic granites from the Fosdick migmatite-granite complex yield U-Pb zircon crystallization ages that range from 115 to 100Ma, with a dominant grouping at 107-100 Ma, which corresponds to the timing of dome formation ... -
Garnet fractionation, progressive melt loss and bulk composition variations in anatectic metabasites: Complications for interpreting the geodynamic significance of TTGs
Kendrick, Jillian; Yakymchuk, Chris (Elsevier, 2020-05)Tonalite-trondhjemite-granodiorite (TTG) suites constitute a large proportion of the Archean geological record; however, the geodynamic processes that generated them, and Archean continental crust in general, remain a ... -
Paleozoic evolution of western Marie Byrd Land, Antarctica
Yakymchuk, Chris; Brown, Caitlin R.; Brown, Michael; Siddoway, Christine S.; Fanning, Christopher Mark; Korhonen, Fawna J. (Geological Society of America, 2015-09-01)We report geochemical data from (meta-) sedimentary and igneous rocks that crop out in the Ford Ranges of western Marie Byrd Land and discuss the evolution and reworking of the crust in this region during Paleozoic subduction ... -
Phase Relations, Reaction Sequences and Petrochronology
Yakymchuk, Chris; Clark, Chris; White, Richard W. (Mineralogical Society of America, 2017-02-01)Phase equilibria modelling has played a key role in enhancing our understanding of metamorphic processes. An important breakthrough in the last three decades has been the ability to construct phase diagrams by integrating ... -
Th/U ratios in metamorphic zircon
Yakymchuk, Chris; Kirkland, Christopher L.; Clark, Chris (Wiley, 2018-03-05)The Th/U ratios of zircon crystals are routinely used to help understand their growth mechanism. Despite the wide application of Th/U ratios in understanding the geological significance of zircon U–Pb ages, the main controls ... -
Visualising data distributions with kernel density estimation and reduced chi-squared statistic
Spencer, Christopher J.; Yakymchuk, Chris; Ghaznavi, Mahmoudreza (Elsevier, 2017-11-01)The application of frequency distribution statistics to data provides objective means to assess the nature of the data distribution and viability of numerical models that are used to visualize and interpret data. Two ...