Brittle basement deformation during the Caledonian Orogeny observed by K‐Ar geochronology of illite‐bearing fault gouge in west‐central Sweden

This study presents K-Ar ages of illite from fault gouges in crystalline basement in centralwestern Sweden. Samples were taken from two faults that localized brittle deformation marginal to and within mafic dikes that intruded Paleoproterozoic granitoids. K-Ar ages from ten separated grain fractions span from 823 to 392 Ma. Older ages obtained (823 to 477 Ma) were influenced by a mixture of illite and K-feldspar; the latter likely formed during a hydrothermal event prior to faulting. The remaining ages (442.1±9.7 to 391.7±6.1 Ma) were obtained from fractions from both faults hosting only authigenic illite, and show that illite crystallized during the Scandian Caledonian orogeny. These results indicate that previously presumed autochthonous Caledonian basement was involved in continental contraction and subsequent collapse of the Caledonian orogen, influencing both the mode and depth of penetration of deformation into Baltica

SAFE MULTIBYGG, Slutrapport Riskidentifiering, analys och åtgärdsmetodik för olycksförebyggande arbete för multifunktionella byggnader med avseende på specifika antagonistiska hot

Multifunktionella byggnader karaktäriseras av att flera olika funktioner (verksamheter) finns inom en och samma byggnad. Ofta är några av funktionerna att betrakta som samhällsviktiga. Brandskyddet i sådana byggnader är av största vikt med hänsyn till att ett stort antal personer kan befinna sig i byggnaden samtidigt som en brand skulle kunna orsaka förlust av samhällsviktiga funktioner. Vidare har det i samhället skett en ökning av antagonistiska attacker. I forskningsprojektet SAFE MULTIBYGG har ett helhetsgrepp tagits över den problematik som finns avseende brandskydd och antagonistiska hot i multifunktionella byggnader. Denna rapport utgör en sammanfattande slutrapport för forskningsprojektet och summerar resultaten av ingående arbetspaket. Projektet har finansierats av MSB, Myndigheten för samhällsskydd och beredskap. Projektet inleddes 2011 och avslutades i december 201

Svecofennian Metamorphic and Tectonic Evolution of East Central Sweden : Research report of a project entitled: Svekofennisk metamorf och tektonisk utveckling i östra mellansverige

In this report we present results from a metamorphic and structural investigation of east central Sweden, and integrate the results with age data into a model of the tectonometamorphic evolution of the region. Metamorphic grades range from medium grade in well-preserved supracrustal areas, like Hamrånge and Los, to granulite facies in intensely migmatized gneisses at Hornslandet, where pyroxene granulites and charnockites have been recorded. Thermobarometry results confirm earlier interpretations of regional low pressure-high temperature (LPM) character of the metamorphism. Results indicating medium or high pressures appear to be related to inappropriate whole-rock chemistry and in particular the CaO content in the samples. Garnets very rarely show growth zoning patterns due to the high temperature during metamorphism but imposed retrograde zoning along garnet margins is common, reflecting cooling of the crust. A PT-path obtained from a growth zoned garnet at Arlanda indicates isobaric temperature increase. Preliminary dating of monazites in pyroxene granulites yield cooling ages of 1846 and 1842 Ma respectively, which may reflect the intrusion of the Ljusdal granitoid rather than regional LPM. In the Los-Edsbyn area an age of 1803±1 Ma has been obtained on metamorphic zircon. The structural evolution comprises at least two major phases of folding and shearing, referred to two deformation episodes, D 1 and D2. Shear zones were formed during both D1 and D2. The former are folded by regional F2 folds and are characterised by complete annealing during the LPM. A preliminary age determination indicates a minimum age of 1826 Ma for D1 shear zones. The kinematics of these zones are unknown. D2 shear zones often truncate limbs of regional F2 folds and there appears to be a close relationship between folding and shearing. The kinematics of the D2 shear zones and their probable relation to F2 folds suggests that previous interpretations for the structural evolution should be revised, both considering principal stress orientation during D2 and the timing of D1 and D2. There is no systematic variation in metamorphic grade related to the existence of steep, regional shear zones. Metamorphic variations appear to reflect thermal variations in the crust possibly related to mafic underplating. Comparison of present crustal thickness and the distribution of granulites in the area and southern Finland indicate postmetamorphic modification of the crust.Svekofennisk metamorf och tektonisk utveckling i östra mellansverig

Structure and stratigraphy of the Dannemora inlier, eastern Bergslagen Region : Primary volcanic textures, geochemistry and deformation

Appendix 1: Revised excerpt from master thesis by Linn BjörbrandAppendix 2: Master thesis by Michaela Åberg (2009), "Taking the Temperature &amp; Pressure on Dannemora"</p

The Storsjön-Edsbyn Deformation Zone, central Sweden : Research report of a project entitled: "The tectonometamorphic history of a major shear zone in central Sweden - integrated geological-geophysical study"

A major, polyphase NNW-SSE-striking deformation zone in central Sweden, 15-30 km wide and &gt;200 km long, apparently separates two major Proterozoic provinces. Four main phases of deformation have been recognized along the deformation zone; associated mylonites are characterized by their mineralogy, microstructures, kinematic patterns, magnetic signatures and relative ages. Locally, metamorphic patterns developed during regional Svecofennian deformation and early shearing were significantly disturbed by later movements on mostly steep, greenschist facies deformation zones. As a result, previously unknown intermediate-high-pressure rocks were juxtaposed against low-pressure rocks more typical for the region. Also the geometry of the major, early Svecofennian Ljusdal Batholith, appears to be controlled by the shear zone and a previously unknown splay. Rotation of planar structures indicates &gt;10-20 km dextral displacement along plastic mylonites. Stress- and strain analysis of mesoscopic shear zone populations of different generations suggests that most displacements are compatible with N-S to NE-SW-oriented bulk regional shortening. Most deformation occurred before intrusion of c. 1.2 Ga mafic dykes and sills. The existence of this deformation zone, however, significantly affected the depositional, metamorphic and structural evolution of the Caledonian orogen in this region.The tectonometamorphic history of a major shear zone in central Sweden - integrated geological-geophysical stud

Deformation Zones in Eastern Bergslagen (Uppland-Sörmland)

In this report we present results from a structural investigation of deformation zones in Eastern Bergslagen. Key areas for investigation have been the NNE-SSW Österbybruk/Skyttorp Zone (ÖSZ), the N-S Gimo Zone (GZ) and the Banded Series in the southeastern Stockholm archipelago. Both the ÖSZ and the GZ is here interpreted to be splays from the Singo Shear Zone (SSZ) system where they originally enveloped tectonic lenses oriented approximately parallel to the SSZ. Solidification of a c. 1.8 Ga granite within the SSZ possibly caused a strain distribution southwards from the SSZ leading to the large scale clock-wise rotation and development of Everging footwall folds to the SSZ. The E-verging fold have steep axes and rotate both the regional foliation as well as the stretching lineation. The ÖSZ and the GZ show E-up kinematics (with a sinistral horizontal component) related to the E-vergent folding. An earlier(?) W-up pattern along the western margin of ÖSZ is here interpreted to be related to a dextral/NE-down shear along the SSZ prior to the folding. The GZ located closer to the SSZ shows generally a higher metamorphic grade than the ÖSZ. Microstructures and chlorite-bearing shearbands of the ÖSZ indicate upper greenschist facies conditions during deformation, while striped gneisses and a C-S fabric with stable hornblende and biotite along both planes indicate amphibolite facies conditions along the GZ. The Banded Series (BS) is a high-T deformation zone exposed on several islands in the Stockholm archipelago (Uto-Orno-Morto-Runmaro-Skarprunmarn). The shear zone evolved from folds and has in turn been folded by regional-scale S-folds. The kinematic pattern iscomplex due to the existence of tectonic lenses, recrystallisation and annealing, and partly due to the later folding of the BS. The tectonic lenses contains hinges of rootless folds with generally NE plunging axes parallel to a very pronounced stretching lineation indicating intense stretching during shearing. Red Kf-augens common within the BS is here interpreted to be derived from dismembered early pegmatites, while white, less common augens were derived form neosomes. These conditions indicate that the BS was temporally related to c. 1816-1821 Ma pegmatites and peak metamorphism. Additional studies of the intensely folded Värmdölandet-Ingarö-Södertörn area has revealed that an important sinistral/W-up shear occurred coeval with an eastward to southeastward hinge escape of the E-W mainland folds. A regional approximately N-S shortening has probably caused both the hinge escape as well as a conjugate, co-existing shear system with a dextral/NE-down (SSZ) and sinistral/NW-up (BS) shear system.Deformationszoner i östra Bergslagen (Uppland-Sörmland): Karaktär och signifikans under svekokarelsk och efterföljande tektonometamorf utvecklin

A modular cross-platform GPU-based approach for flexible 3D video playback

Different compression formats for stereo and multiview based 3D video is being standardized and software players capable of decoding and presenting these formats onto different display types is a vital part in the commercialization and evolution of 3D video. However, the number of publicly available software video players capable of decoding and playing multiview 3D video is still quite limited. This paper describes the design and implementation of a GPU-based real-time 3D video playback solution, built on top of cross-platform, open source libraries for video decoding and hardware accelerated graphics. A software architecture is presented that efficiently process and presents high definition 3D video in real-time and in a flexible manner support both current 3D video formats and emerging standards. Moreover, a set of bottlenecks in the processing of 3D video content in a GPU-based real-time 3D video playback solution is identified and discussed.Digital 3D-rekla