Svecofennian magmatic and metamorphic evolution in southwestern Finland as revealed by U-Pb zircon SIMS geochronology

Zircons from six samples collected from igneous and metamorphic rocks were dated using the NORDSIM ion microprobe, in order to investigate the tectonic evolution of the Palaeoproterozoic Svecofennian Orogen in southwestern Finland. These rocks represent pre-collisional, collisional and post-collisional stages of the orogeny. The ion microprobe results reveal two age groups of granodioritic-tonalitic rocks. The intrusions have different tectonic settings: the Orijärvi granodiorite represents pre-collisional 1.91-1.88 Ga island-arc-related magmatism and yielded an age of 1898 ± 9 Ma, whereas the collision-related Masku tonalite was dated at 1854 ± 18 Ma. The latter age accords with more accurate previous conventional zircon age data and constrains the emplacement age of collisional granitoids to ≈ 1.87 Ga. This is interpreted to reflect the collision between the Southern Svecofennian Arc Complex with the Central Svecofennian Arc complex and the formation of a suture zone between them during D2 deformation. Granulite facies metamorphism in the Turku area was dated at 1824 + 5 Ma using zircons from leucosome in the Lemu metapelite. This age constrains D3 folding related to post-collisional crustal shortening in this area. Crustal melting continued until ≈ 1.81 Ga, as indicated by the youngest leucosome zircons and metamorphic rims of enderbite zircons. New metamorphic zircon growth took place in older granitoids at granulite facies, but not at amphibolite facies. Detrital zircons with ages between 2.91 and 1.97 Ga were found in the mesosome of the Lemu metapelite and 2.64-1.93 Ga inherited cores were found in the 1.87 Ga Masku tonalite. © 2002 Elsevier Science B.V. All rights reserved.</p

1.90-1.88 Ga arc and back-arc basin in the Orijärvi area, SW Finland

The Orijärvi area within the Uusimaa Belt is a key area in resolving the stratigraphy and tectonic setting of the Southern Svecofennian Arc Complex in southern Finland. Based on field relationships, geochemistry and radiometric age determinations, the area can be divided into four formations. The bimodal Orijärvi formation, lowermost in stratigraphy, is exposed in an antiform containing the synvolcanic Orijärvi granodiorite in its core. Basalts have high LILE/HFSE ratios with pronounced negative Nb-Ta anomalies. The basalts in the lower part of the Orijärvi formation are geochemically less evolved than the basalts and basaltic andesites at higher levels. A rhyolite from a low stratigraphic level in the Orijärvi formation yielded a U-Pb zircon age of 1895.3±2.4 Ma. The Kisko formation stratigraphically overlies the Orijärvi formation and the compositions of the volcanic rocks range from basalts to rhyolites. These mafic and intermediate rocks also show high LILE/HFSE ratios but the total element abundances are higher and show a more pronounced LREE enrichment, compared to the Orijärvi formation, indicating an evolved magma system. A dacite from the upper part of the Kisko formation yielded a U-Pb zircon age of 1878.2±3.4 Ma. The Salittu formation probably overlies the Kisko formation. It mainly comprises picrites and tholeiitic pillow lavas with mica gneisses and minor marbles as intercalations. It differs from the underlying formations showing higher Mg, Ti and Zr contents and higher LILE/HFSE ratios. The major and trace element compositions indicate an oceanic affinity. The Toija formation evidently underlies the Salittu formation and comprises mafic pillow lavas, rhyolites, marbles, and one picritic horizon. The geochemical characteristics are transitional between the Salittu and Orijärvi/Kisko formations. All the formations contain both concordant and crosscutting intrusive rocks, some of which are comagmatic with the volcanic rocks. In tectonomagmatic discrimination diagrams the Orijärvi and Kisko formations plot in the island arc field and the Salittu formation plots in the E-MORB field. High LILE/HFSE ratios, typical of subduction-related volcanic rocks, characterize the Orijärvi and Kisko formations, whereas such a subduction component is less prominent in the Toija formation and is missing in the Salittu formation. Geochemistry and age relationships suggest that the Orijärvi formation was formed during the initial stages of volcanic arc evolution in an extensional tectonic regime, and the Kisko formation represents a mature stage of arc evolution. Subsequent extension of the island arc is manifested by the ultramafic/ mafic Salittu formation with E-MORB-like chemistry, interpreted to indicate a back-arc basin. The Toija formation might represent an initial stage of back-arc rifting.</p

Time, institutional support and quality of decision making in child protection:A cross-country analysis

This paper examines perceptions of time and institutional support for decision making and staff confidence in child welfare staffs ultimate decisions – examining differences and similarities between and within the service-oriented Nordic countries (Norway and Finland) and the risk-oriented Anglo-American countries (England and California). The study identifies a high degree of work pressure across all the countries, lines of predominantly vertical institutional support and relatively high confidence in decisions. Finland stands out with higher perceived work pressure and with a horizontal support line, whereas England stands out with workers having a lower degree of confidence in their own and others’ decisions

Preservation of Palaeoproterozoic early Svecofennian structures in the Orijärvi area, SW Finland-Evidence for polyphase strain partitioning

The predominantly migmatitic Palaeoproterozoic Uusimaa belt preserves early lower-grade Svecofennian structures in the Orijärvi area in SW Finland. This study aims at explaining the deformational history responsible for its preservation and also at defining the age of the early Svecofennian deformation. Detailed structural analysis reveals that the preservation was enabled by polyphase strain partitioning, which initiated during the early Svecofennian D deformation, ∼1875 Ma ago, as revealed by ion microprobe U-Pb data on zircons from granodioritic and intermediate syn-D intrusive dykes. The D structures were low-strain upright folds at high crustal levels and sub-horizontal high-strain folds at deeper crustal levels. The sub-horizontal D structures were refolded into upright folds during the subsequent late Svecofennian D deformation, whereas the upright D structures behaved as almost rigid blocks that caused strain partitioning into high-strain zones along the block margins. This accounts for the low cumulative strain in specific parts of the Orijärvi area. Further strain partitioning during D caused reverse dip-slip movements along regional-scale shear zones. Crustal depth controlled the metamorphic grade during D , when local migmatisation took place at deep crustal levels. Later metamorphic overprint during D deformation is evident from post-D growth of sillimanite and a second generation of andalusite. Similarities in the structural patterns between the Orijärvi area and the Tampere-Vammala area (∼100 km to the north) suggest that irrespective of the age of the later overprint, subsequent deformation was localised along the margins of the early formed upright domains, while the low-grade rocks within the domains were preserved. © 2006 Elsevier B.V. All rights reserved.</p

Metaphorical and interlingual translation in moving organizational practices across languages

Organizational scholars refer to translation as a metaphor in order to describe the transformation and movement of organizational practices across institutional contexts. However, they have paid relatively little attention to the challenges of moving organizational practices across language boundaries. In this conceptual paper, we theorize that when organizational practices move across contexts that differ not only in terms of institutions and cultures but also in terms of languages, translation becomes more than a metaphor; it turns into reverbalization of meaning in another language. We argue that the meeting of languages opens up a whole new arena for translator agency to unfold. Interlingual and metaphorical translation are two distinct but interrelated forms of translation that are mutually constitutive. We identify possible constellations between interlingual and metaphorical translation and illustrate agentic translation with published case examples. We also propose that interlingual translation is a key resource in the discursive constitution of multilingual organizations. This paper contributes to the stream of research in organization studies that has made translation a core aspect of its inquiry

How adherence to the updated physical activity guidelines should be assessed with accelerometer?

BackgroundThe aerobic part of the recently updated physical activity (PA) guidelines for adults recommends at least 150 min of moderate or at least 75 of vigorous-intensity PA or an equivalent combination of both. PA can be accumulated of any bout duration. On an absolute scale, moderate-intensity threshold is 3 metabolic equivalents (METs) and vigorous 6 METs. On a scale relative to individual’s personal capacity, moderate-intensity threshold is 40% and vigorous 60% of the oxygen uptake reserve. In this study, the adherence to the new guidelines was evaluated using both absolute and relative thresholds.MethodsTotally, 1645 adults aged 20–64 years, participated in this population-based study and their cardiorespiratory fitness (CRF) was estimated with 6-min walking test. The participants with estimated maximal oxygen uptake ResultsThe adequate CRF group had higher adherence to PA guidelines with the absolute thresholds, but the use of relative thresholds inverted the results. The adherence varied from 20% to 99% in the total sample depending on the analysis parameters of accelerometer data.ConclusionsThe absolute thresholds provide a more appropriate basis to assess the adherence to PA guidelines in population-based samples and interventions. The use of individually determined relative thresholds may be more useful for individual exercise prescriptions in PA counseling.</p

How adherence to the updated physical activity guidelines should be assessed with accelerometer?

BACKGROUND: The aerobic part of the recently updated physical activity (PA) guidelines for adults recommends at least 150 min of moderate or at least 75 of vigorous-intensity PA or an equivalent combination of both. PA can be accumulated of any bout duration. On an absolute scale, moderate-intensity threshold is 3 metabolic equivalents (METs) and vigorous 6 METs. On a scale relative to individual's personal capacity, moderate-intensity threshold is 40% and vigorous 60% of the oxygen uptake reserve. In this study, the adherence to the new guidelines was evaluated using both absolute and relative thresholds. METHODS: Totally, 1645 adults aged 20-64 years, participated in this population-based study and their cardiorespiratory fitness (CRF) was estimated with 6-min walking test. The participants with estimated maximal oxygen uptake <7.9 MET were categorized as low CRF group and the others as adequate CRF group. The participants were instructed to wear a triaxial hip-worn accelerometer for 1 week and their adherence to PA guidelines was assessed from the accelerometer data. RESULTS: The adequate CRF group had higher adherence to PA guidelines with the absolute thresholds, but the use of relative thresholds inverted the results. The adherence varied from 20% to 99% in the total sample depending on the analysis parameters of accelerometer data. CONCLUSIONS: The absolute thresholds provide a more appropriate basis to assess the adherence to PA guidelines in population-based samples and interventions. The use of individually determined relative thresholds may be more useful for individual exercise prescriptions in PA counseling.publishedVersionPeer reviewe