Results 51 to 60 of about 842 (183)

Potential Warming‐Induced Changes in Stream Water Sources Between Proglacial and Non‐Glacial Streams, South‐Central Alaska

Hydrological Processes, Volume 40, Issue 8, August 2026.
Land cover and elevation are shown to influence the proportion of stream source waters across glacial and non‐glacial streams. Groundwater makes up a large proportion of both early season and late season flow in most glacial and non‐glacial streams, while the timing of snow and ice melt is driven by the presence or absence of a glacier within the ...
H. K. Richardson, A. J. Bergstrom, J. C. Koch, Z. A. Frederick, J. B. Shanley, E. H. Baker   +5 more
wiley   +1 more source

Source and tectono-metamorphic evolution of mafic and pelitic metasedimentary rocks from the central Quetico metasedimentary belt, Archean Superior Province of Canada [PDF]

Precambrian Research, 2004
Abstract A study of the sedimentary rocks in the Jean Lake area of the Quetico metasedimentary belt, Superior Province, Canada, was conducted in order to evaluate the origin, source, and evolution of rocks, including mafic rocks previously mapped as ultramafics rocks. Bulk compositions of these sedimentary rocks show a mixing between two end members:
Valli, Franck, Guillot, Stéphane, Hattori, Kéiko   +2 more
openaire   +2 more sources

Carbonate‐Associated Sulfate Does Not Record Superheavy δ34S in Deep Scandinavian Bedrock Fractures: Implications for Pyrite Formation in the Deep Biosphere

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 8, August 2026.
Abstract In deep bedrock fractures of the Fennoscandian shield, pyrite with “superheavy” δ34S values of up to 147‰ exists together with calcite. The extreme variability and 34S‐enrichment in pyrite indicate that microbial sulfate reduction (MSR) evolved to almost complete sulfate exhaustion in closed‐system microenvironments.
V. Fichtner, F. Genske, E. Kooijman, H. Drake   +3 more
wiley   +1 more source

Sources and source areas of the Upper Paleozoic metasedimentary rocks of the Dzhagda terrane of the Mongol-Okhotsk fold belt: the results of Sm-Nd isotope geochemical studies

Геодинамика и тектонофизика, 2018
The article presents the results of Sm-Nd isotope geochemical studies of the Upper Paleozoic metasedimentary rocks of the Dzheskogon, Nektera and Bochagor suites of the Dzhagda terrane.
V. A. Zaika, A. A. Sorokin, V. P. Kovach
doaj   +1 more source

Magnetic fabric and rock magnetic studies of metasedimentary rocks in the central Okcheon Metamorphic Belt, Korea [PDF]

Earth, Planets and Space, 2005
Abstract Anisotropy of magnetic susceptibility (AMS) and rock magnetic studies have been carried out for the metasedimentary rocks in the central Okcheon Metamorphic Belt. The study area is divided into three metamorphic zones: the biotite zone, the garnet zone, and the sillimanite+andalusite zone from southeast to northwest.
Park, Yong-Hee, Doh, Seong-Jae, Kim, Wonnyon, Suk, Dongwoo   +3 more
openaire   +1 more source

Vanadium Isotopic Compositions of the High‐3He/4He Baffin Island Lavas

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 8, August 2026.
Abstract The isotopic composition of vanadium (V) in hotspot lavas provides new insight into the source of deep mantle heterogeneities. We measured V isotopic compositions in Paleogene Baffin Island lavas, which erupted above the Iceland plume head, to constrain the mantle plume source. These lavas have V isotopic compositions that are lighter (−0.96 ± 
Jonas Kaare‐Rasmussen, Forrest Horton, Maureen Auro, Andy W. Heard, Sune G. Nielsen   +4 more
wiley   +1 more source

U-Pb zircon age of Ordovician magmatism in the Albera Massif (Eastern Pyrenees)

Geologica Acta, 2011
New geochronological data from the Albera Massif confirm the presence of an Early – Mid Ordovician igneous event (472 - 465Ma) recorded in the pre-Variscan rocks of the Pyrenees.
M. LIESA TORRE-MARÍN, J. CARRERAS, P. CASTIÑEIRAS GARCÍA, J.M. CASAS, M. NAVIDAD, M. VILÀ   +5 more
doaj  

Structurally‐Controlled Permeability Evolution and Mineralization in Geothermal Caprocks: The Fenice Capanne Mining District (Southern Tuscany, Italy)

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 8, August 2026.
Abstract The Neogene mineralized region of the Colline Metallifere in southern Tuscany (Italy) provides a natural laboratory to investigate feedback between fluid–rock interaction, structurally controlled fluid flow, and hydrothermal ore mineralization.
Barbara Marchesini, Federico Rossetti, Ahmad Rabiee, Andrea Billi, Andrea Cavallo, Davide Novella, Vincenzo Moretto, Antonio Caracausi, Fabio Trippetta, Luca Aldega, Luigi Dallai, Giovanni Ruggieri, Eugenio Carminati   +12 more
wiley   +1 more source

Hybridization between I-type and S-type granites in the ordovician famatinian magmatic arc, Tafí del Valle, Tucumán, NW Argentina

Geologica Acta, 2018
In the Tafí del Valle region, in northwestern Argentina, several intrusive bodies of lower Paleozoic age were emplaced in the metasedimentary Puncoviscana Formation, belonging to the Sierras Pampeanas. Four intrusive bodies outcrop in the study area: La
J.P. LÓPEZ, L.I. BELLOS, J. DÍAZ-ALVARADO, A. CASTRO   +3 more
doaj  

Detrital zircon geochronology of Paleoproterozoic metasedimentary rocks from Jämsä, Central Finland [PDF]

Bulletin of the Geological Society of Finland
In this short communication, we present new detrital single grain zircon U-Pb data for six metasedimentary rock samples from Jämsä, Central Finland.
Perttu Mikkola, Matti Kurhila, Hannu Huhma   +2 more
doaj   +1 more source