Results 51 to 60 of about 3,332 (193)

Two Cycles of Devonian–Triassic Extension and Compression in the Altai Accretionary Wedge: Insights From Tsogt Core Complex

Tectonics, Volume 44, Issue 12, December 2025.
Abstract The Altai Accretionary Wedge in the Mongolian Altai records a polyphase geodynamic evolution involving two extensional–compressional tectonic cycles, constrained by petrostructural analysis and zircon, monazite U–Pb, and Ar–Ar geochronology. The studied section includes a southwestern high‐grade and a northeastern low‐grade domain, previously ...
O. Lexa, P. Jeřábek, K. Schulmann, M. Racek, Y. Jiang, A. R. C. Kylander‐Clark, J. Míková, R. Spikings   +7 more
wiley   +1 more source

Tectonics, geology and origins of Te Riu‐a‐Māui / Zealandia

New Zealand Journal of Geology and Geophysics, Volume 68, Issue 4, Page 531-567, December 2025.
ABSTRACT Te Riu‐a‐Māui / Zealandia is a 95% submerged, five million square km southern hemisphere continent that includes the islands of New Zealand and New Caledonia. For the last 45 million years (Ma) Zealandia has been cut by the Pacific‐Australian plate boundary which today changes character from a west‐dipping subduction zone in the north to ...
Nick Mortimer
wiley   +1 more source

Stockscheider Quartzo-Moscovíticos e Pegmatíticos na Zona de Cúpula do Granitóide Ritápolis, Região de São João del Rei, Minas Gerais [PDF]

Anuário do Instituto de Geociências, 2011
Em quatro áreas da Província Pegmatítica de São João del Rei são encontrados clusters de corpos constituídos basicamente por quartzo-moscovita, que estão em estreita associação com pegmatitos posicionados paralelamente à zona de cúpula do granitóide ...
Ronaldo Mello Pereira, Diana Rodrigues, Ciro Alexandre Ávila, Reiner Neumann   +3 more
doaj  

Chemical reaction between amphibolites and quartzo-feldspathic veins

The Journal of the Japanese Association of Mineralogists, Petrologists and Economic Geologists, 1970
Reaction zones are observed between amphibolites and quartzo-feldspathic veins. They are formed under upper amphibolite facies. Typical reaction zone is as follow: Actinolite+anorthite+quartz/ Biotite+actinolite+plagioclase+quartz/ Biotite+plagioclase+quartz// Biotite+plagioclase+quartz/ Biotite±cordierite+oligoclase+quartz±orthoclase.
openaire   +2 more sources

Fluid or Melt? Distinguishing Syn‐Deformational Interaction Pathways

Journal of Metamorphic Geology, Volume 43, Issue 8, Page 810-838, October 2025.
ABSTRACT Understanding whether deformation occurred in the presence of aqueous fluid or silicate melt is crucial for interpreting ductile shear zones, impacting their thermal and geochemical evolution, and having rheological consequences. To identify the syn‐deformational fluid type, we investigate contrasting shear zones active during the Alice ...
Hindol Ghatak, Nathan R. Daczko, Sandra Piazolo, Tom Raimondo   +3 more
wiley   +1 more source

Zircon (Re)crystallization During Metamorphism: Zircon Paragenesis in the Papua New Guinea Coesite Eclogite Revisited

Journal of Metamorphic Geology, Volume 43, Issue 7, Page 663-680, September 2025.
ABSTRACT The youngest known ultrahigh‐pressure (UHP) eclogite from Tumagabuna Island, a small island of the D'Entrecasteaux Islands chain in Papua New Guinea, exhibits zircon U–Pb age variations spanning a few million years. This age variation complicates the interpretation of the evolution of this high and ultrahigh‐pressure ([U]HP) terrane.
Linus B. Streicher, Fraukje M. Brouwer, Keewook Yi, Suzanne L. Baldwin, Wim van Westrenen   +4 more
wiley   +1 more source

Interação entre magmas graníticos e a origem de epissienitos potássicos estaníferos do granito Madeira, mina Pitinga, Amazonas

Geologia USP. Série Científica, 2018
O estudo petrográfico de amostras da zona de contato entre as fácies albita-granito de borda e feldspato alcalino-granito hipersolvus porfirítico, na borda oeste do plúton Madeira, identificou rochas com características texturais e composicionais ...
Régis Munhoz Krás Borges, Sulsiene Machado de Souza Gaia, Hilton Tulio Costi, Claudio Nery Lamarão, Gisele Tavares Marques   +4 more
doaj   +1 more source

Depth of Ancient Seismicity Along the Woodroffe Thrust (Central Australia): Constraints From Pseudotachylytes in Peraluminous Gneisses

Tectonics, Volume 44, Issue 8, August 2025.
Abstract The Woodroffe Thrust (WT) is a regional‐scale mylonitic shear zone that developed during the Petermann Orogeny (630–520 Ma) in lower to mid‐crustal rocks of the Musgrave Ranges, central Australia. In the upper part the WT hosts the largest volume worldwide of tectonic pseudotachylytes (coseismic quenched frictional melts). The pseudotachylytes
G. Toffol, A. Camacho, N. Mancktelow, G. Pennacchioni   +3 more
wiley   +1 more source

Schist Belts of the Benin‐Nigeria Shield Reveal a Neoproterozoic History

Terra Nova, Volume 37, Issue 4, Page 239-249, August 2025.
ABSTRACT Belts of metasedimentary rocks (schist belts) in the Benin‐Nigeria Shield (BNS) are investigated for the first time using U–Pb dating and Lu‐Hf isotope analysis of detrital zircons. We report maximum depositional ages that place their deposition firmly in the Neoproterozoic and link them with strata in the Dahomey Belt, the central African ...
Axel Hofmann, Silas Dada, Samuel B. Olobaniyi, Isaac Ajigo, Marlina Elburg, Fabricio A. Caxito, Andrey Bekker   +6 more
wiley   +1 more source

Novos dados geológicos e isotópicos para o Domínio Iriri-Xingu, Província Amazônia Central: implicações para a idade do Grupo Iriri

Geologia USP. Série Científica, 2016
O Domínio Iriri-Xingu, sul da Província Amazônia Central, é uma das regiões geologicamente menos conhecidas do Cráton Amazônico. Nela predominam rochas vulcânicas e granitóides paleoproterozoicos e o embasamento regional raramente aflora.
Flávio Robson Dias Semblano, Nayan Cezar S. Pereira, Marcelo Lacerda Vasquez, Moacir José Buenano Macambira   +3 more
doaj   +1 more source