The Distinct Metamorphic Stages and Structural Styles of the 1.94–1.86 Ga Snowbird Orogen, Northwest Territories, Canada

Palaeoproterozoic orogenesis within the Archean southeastern Rae craton is related to the initial amalgamation of Laurentia. Characterizing the accompanying tectonic processes during this time has been complicated due to polymetamorphism, which results in the obscuring of the age record of the terranes involved. To improve the knowledge of the tectonic evolution of the South Rae Craton, petrologic and structural analyses are applied in conjunction with in situ trace element chemistry, inclusion barometry, U–Pb monazite and titanite, and Lu–Hf garnet chronology. The data robustly constrain Palaeoproterozoic pressure–temperature–time paths of major deformational events along the southeastern Rae craton margin. D1 occurred between 1.94 and 1.93 Ga in the Dodge-Snowbird domain, which included prograde burial of metasedimentary rocks, deposited at 2.2–2.0 Ga, and the development of migmatitic layering and east-southeast trending folds (S1, F1). Peak metamorphism is recorded in metasedimentary units at c. 1.93 Ga when rocks reached conditions of 9.0–10.5 kbar and 810–830°C. Within the Dodge-Snowbird domain, D2 imparted north-northeast trending open folds and associated axial planar cleavage (S2, F2) between 1.93 and 1.90 Ga during east-west compression that appears to have been synchronous with cooling and exhumation. Later D2 deformation, localized within the Wholdaia Lake shear zone (WLsz; ST1), developed in the footwall of this thrust-sense structure at 1,873 ± 5 Ma at conditions of 9.5–11.0 kbar and 820–850°C. The hangingwall Dodge-Snowbird domain had already cooled to below 300°C by then, indicating a significant structural and metamorphic break across the domain\u27s western boundary. A new phase of unroofing (D3) involved pervasive amphibolite- to greenschist facies extensional shearing (ST2) within the WLsz, which overprinted ST1 foliations between 1.87 and 1.86 Ga. Continued greenschist facies shearing younger than 1.86 Ga likely ended by c. 1.83 Ga when lamprophyre dykes cut the structure, which was followed by cooling until c. 1.80 Ga. This work highlights the utility and application of multiple chronometers (zircon, monazite, titanite, garnet) along with structural and petrologic analysis that together can resolve precise orogenic cycles in polymetamorphic terranes that may otherwise be undetected. The time-resolved P–T–D histories derived here enable more robust interpretations regarding the nature and evolution of 1.9 Ga tectonism along the southeast Rae craton margin, which may be used to refine models for Laurentian terrane amalgamation

Att locka och behålla : En kvalitativ studie om två organisationers arbete med employer branding

Tidigare forskning har visat att rörligheten på arbetsmarknaden har ökat och att det finns en brist på kvalificerade arbetare. Arbetsgivarna har försökt att uppmärksamma detta problem genom att arbeta på sitt employer brand. Detta görs genom att skapa en attraktiv organisation samt genom att behålla de redan anställda med hjälp av att engagera och förstärka dem. Studiens syfte har varit att undersöka hur en större organisation (med ca. 1000 anställda) jämfört med en mindre organisation (med ca. 15 anställda) arbetar med employer branding. Frågeställningarna studien kommer att besvara är “hur arbetar en större organisation jämfört med en mindre organisation för att attrahera nya potentiella medarbetare?” och “hur arbetar en större organisation jämfört med en mindre organisation med att behålla sina medarbetare?”. Studiens syfte delades in i två delar: den externa delen som behandlar hur organisationer marknadsför sitt varumärke samt hur de attraherar nya medarbetare, och den interna delen som behandlar hur organisationen arbetar för att behålla sina nuvarande medarbetare med hjälp av feedback, socialt stöd, engagemang, utvecklingsmöjligheter samt trivsel.   Studien har genomförts med en kvalitativ ansats med semistrukturerade intervjuer från två olika organisationer inom rekryteringsbranschen. Alla valda intervjupersoner besitter en expertis inom området, därmed klassas samtliga intervjuer som expertintervjuer. Trots den semistrukturerade formen på intervjuerna var det viktigt för studien att ha med ett par frågor som var essentiella för att kunna besvara studiens frågeställningar. Studiens resultat visade att båda organisationerna arbetar med sitt employer brand, dock hade de väldigt olika tillvägagångssätt med tanke på organisationernas olika storlek. Den större organisationen hade ett mer strukturellt och formellt tillvägagångssätt inom den interna delen. Medan den mindre organisationen använde sig av ett informellt sätt för utförande av de interna delarna

The Ferguson Lake deposit: an example of Ni-Cu-Co-PGE mineralization emplaced in a back-arc basin setting?

The world’s largest Ni–Cu–Platinum group element (PGE) deposits are dominantly hosted by ultramafic rocks within continental extensional settings (e.g., Raglan, Voisey’s Bay), resulting in a focus on exploration in similar geodynamic settings. Consequently, the economic potential of other extensional tectonic environments, such as ocean ridges and back-arc basins, may be underestimated. In the northeastern portion of the ca. 2.7 Ga Yathkyed greenstone belt of the Chesterfield block (western Churchill Province, Canada), the Ni–Cu–Co–PGE Ferguson Lake deposit is hosted by >2.6 Ga hornblenditic to gabbroic rocks of the Ferguson Lake Igneous Complex (FLIC), which is metamorphosed up to amphibolitic facies. The FLIC has a basaltic composition (Mg# = 31–72), flat to slightly negatively sloped normalized trace element patterns (La/YbPM = 0.7–3.5), and negative Zr, Ti, and Nb anomalies. The FLIC rocks are geochemically similar to the 2.7 Ga back-arc basin tholeiitic basalts from the adjacent Yathkyed and MacQuoid greenstone belts (Mg# = 30–67; La/YbPM = 0.3–3.0), but the Ferguson Lake intrusions appear to be more crustally contaminated. We interpret the FLIC to have formed in an equivalent back-arc basin setting. This geodynamic setting is rare for the formation of Ni–Cu–PGE occurrences, and only few examples of this tectonic environment (or variations of it, e.g., rifted back-arc) are found in other Proterozoic and Archean sequences (e.g., Lorraine deposit, Quebec). We suggest that back-arc basin-derived mafic rocks within the Yathkyed and other Neoarchean greenstone belts of the Chesterfield block (MacQuoid and Angikuni) could represent important targets for future mineral exploration.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Provenance, Stratigraphic and Precise Depositional Age Constraints for an Outlier of the 1.9 to 1.8 Ga Nonacho Group, Rae Craton, Northwest Territories, Canada

The Nonacho Group comprises six formations of continental clastic rocks that were deposited between 1.91 and 1.83 Ga. The Nonacho Group is part of a broader assemblage of conglomerate and sandstone that was deposited atop the Rae craton in response to the amalgamation of Laurentia and supercontinent Nuna, but the details of its tectonic setting are contentious. This paper documents an outlier of Nonacho Group rocks ∼50 km east of the main Nonacho basin. Field observations and LA-ICPMS (laser ablation inductively coupled plasma mass spectrometry) U-Pb detrital zircon geochronology are integrated with previous studies of the main basin to better understand the group’s depositional history, provenance and tectonic setting. The lithology and detrital zircon age spectra of the outlier allow for its correlation to the upper two formations of the Nonacho Group. CA-ID-TIMS (chemical abrasion isotope dilution thermal ionization mass spectrometry) analyses of two fragments of the youngest detrital zircon provide a maximum depositional age of 1901.0 ± 0.9 Ma. A felsic volcanic cobble dated at ca. 2.38 Ga provides evidence of volcanism during the Arrowsmith orogeny. Detrital zircon dates recovered from the outlier (ca. 3.4–3.0, 2.7, 2.5–2.3 and 2.0–1.9 Ga) are consistent with derivation from topography of the Taltson and/or Thelon orogens on the western margin of the Rae craton. Taltson-Thelon (2.0 to 1.9 Ga) aged detritus is only abundant in the upper two formations of the Nonacho Group, marking a change in provenance from the lower formations. This change in provenance may have coincided with a period of renewed uplift and the unroofing of Taltson-Thelon plutons. The detrital zircon provenance and depositional age of the Nonacho Group is consistent with models that link its deposition to the Taltson and/or Thelon orogens. However, tectonism associated with the 1.9 to 1.8 Ga Snowbird and Trans-Hudson orogens to the east could also have affected basin formation or the change in provenance from the lower to upper Nonacho Group. This study highlights the importance of CA-ID-TIMS in establishing accurate and precise maximum depositional ages for sedimentary successions