Results 31 to 40 of about 970 (117)
Detrital zircon geochronology of Paleoproterozoic metasedimentary rocks from Jämsä, Central Finland [PDF]
Bulletin of the Geological Society of FinlandIn this short communication, we present new detrital single grain zircon U-Pb data for six metasedimentary rock samples from Jämsä, Central Finland.
Perttu Mikkola +2 more
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Rare Earth Elements in Middle Precambrian Volcanic Rocks of Finland, with a Discussion of the Origin of the Rocks [PDF]
Bulletin of the Geological Society of Finland, 1975 The contents of rare earth elements (REE) have been determined in five Svecofennian metamorphosed volcanic rocks and are compared with those found in the Karelian zone and Recent tholeiites.
T. Koljonen, R.J. Rosenberg
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Journal of Geophysical Research: Solid Earth, Volume 128, Issue 4, April 2023., 2023 Abstract We analyze envelopes of 233 and 22 ML0.0 to ML1.8 earthquakes induced by two geothermal stimulations in the Helsinki, Finland, metropolitan area. We separate source spectra and site terms and determine intrinsic attenuation and the scattering strength of shear waves in the 3–200 Hz frequency range using radiative transfer based synthetic ...
Tom Eulenfeld +3 more
wiley +1 more source
Petrographic studies and mineralogical characterization of the Dellen impactites
Meteoritics &Planetary Science, Volume 58, Issue 4, Page 480-500, April 2023., 2023 Abstract The impact origin of the Early Cretaceous (140.82 ± 0.51 Ma) 20‐km diameter Dellen structure was proven in the late 60s based on the discovery of planar deformation features (PDFs) in quartz grains. Although decades have passed, impactites found from the crater have not received much attention. Thus, this study provides a detailed petrological
Satu Hietala +2 more
wiley +1 more source
Zircon dating of the basalt and felsic dyke in Haveri, SW Finland [PDF]
Bulletin of the Geological Society of Finland, 2022 The E-MORB type Haveri basalt differs from the volcanic arc type rocks in the Tampere belt showing no subduction signature. It is considered to have formed in a marginal basin prior to the volcanic arc. We present here zircon U-Pb dating on two samples.
Jaakko Kara +2 more
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The Salittu Formation in southwestern Finland, part I: Structure, age and stratigraphy [PDF]
Bulletin of the Geological Society of Finland, 2016 Because of the relatively low metamorphic grade, low strain and well-preserved early structures in volcanic and volcaniclastic rocks, the Orijärvi triangle (in the center of the larger Orijärvi area) is one of the few locations in the Svecofennian orogen
M. Nironen, I. Mänttäri, M. Väisänen
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Nonsystematic Rupture Directivity of Geothermal Energy Induced Microseismicity in Helsinki, Finland
Journal of Geophysical Research: Solid Earth, Volume 128, Issue 3, March 2023., 2023 Abstract The rupture behavior of microseismicity in fluid‐injection settings with low fault stresses is generally believed to be controlled by the pore pressure, including a tendency of the larger induced earthquakes to rupture into the perturbed volume toward the injection well, implying a degree of predictability.
J. M. Holmgren, G. Kwiatek, M. J. Werner
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1.88 Ga granitoids at Sorsakoski, Central Finland: A-type magmatism within the Raahe-Ladoga suture zone [PDF]
Bulletin of the Geological Society of FinlandFour quartz monzonite – granite intrusions forming the Sorsakoski granite lithodeme, are found within the Raahe-Ladoga suture zone in Central Finland. The prevailing potassium feldspar megacrystic quartz monzonites and granites form a bimodal association
Perttu Mikkola +3 more
doaj +1 more source
Transactions of the Karelian Research Centre of the Russian Academy of Sciences, 2018 A 3D model of the deep structure of the Late Paleoproterozoic Svecofennian accretionary orogen is presented. The model is based on coordinated data of geological mapping, seismic reflection surveys along the profiles FIRE-2-2a-1 and FIRE-3-3a ...
Михаил Вениаминович Минц +5 more
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The Luusika potential field anomaly, eastern Estonia: modelling results [PDF]
Estonian Journal of Earth Sciences, 2018 This study considers the anomalous gravity and magnetic fields in the Alutaguse petrological–structural domain, eastern Estonia. A 10 km wide local maximum (+6.26 mGal) Bouguer anomaly field was discovered at 58.96°N, 26.61°E from the ground gravity data
Marija Dmitrijeva +2 more
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