Fluid controlled eclogitization of granulites in deep crustal shear zones, Bergen arcs, Western Norway

1990 ◽  
Vol 104 (2) ◽  
pp. 184-193 ◽  
Author(s):  
Bj�rn Jamtveit ◽  
Kurt Bucher-Nurminen ◽  
H�kon Austrheim
Keyword(s):  
Shear Zones ◽  
Western Norway ◽  
Crustal Shear Zones

scholarly journals Shape of plutons in crustal shear zones: A tectono-magmatic guide based on analogue models

2021 ◽  
pp. 104417
Author(s):  
Maria Michail ◽  
Michael Rudolf ◽  
Matthias Rosenau ◽  
Alberto Riva ◽  
Piero Gianolla ◽  
...  
Keyword(s):  
Shear Zones ◽  
Analogue Models ◽  
Crustal Shear Zones

Cratonic Reactivation in the Precambrian Basement of Western Canada. III. Crustal Evolution

1973 ◽  
Vol 10 (2) ◽  
pp. 283-291 ◽  
Author(s):  
R. A. Burwash ◽  
J. Krupička ◽  
R. R. Culbert
Keyword(s):  
Shear Zones ◽  
Western Canada ◽  
Upward Movement ◽  
Low Velocity ◽  
Reflection And Refraction ◽  
Refraction Seismic ◽  
Southern Alberta ◽  
Crustal Shear Zones ◽  
Crustal Reflection ◽  
Velocity Zone

Relative to the Superior and Slave provinces, the Churchill province is enriched in K and Rb. The inferred mechanism of alkali enrichment involves diapiric uprise of mantle material from the base of the low velocity zone, in response to upward movement of water from the deep mantle. Intergranular fluid in the peridotite is enriched in K and Rb. At the base of the crust this fluid separates to enter deep-seated crustal shear zones. At upper crustal levels, reaction with permeable cataclasites causes K-metasomatism, involving especially the change of plagioclase into K-feldspar.Eclogite bodies within the peridotite, on moving upward to the base of the crust yield andesitic magma which separates to form sialic underplating. The existence of a discrete lower crust beneath southern Alberta, western Ontario, and northern Manitoba is shown by deep crustal reflection and refraction seismic studies.Generation of juvenile sial during the Hudsonian orogeny is indicated by initial ratios of whole-rock Rb–Sr isochrons for igneous rocks. During metasomatism, potassium and rubidium were added in the ratio of about 350:1. This ratio makes it unlikely that these alkalis were derived by anatexis of Kenoran crystalline basement.

CRUSTAL SHEAR ZONES AND THE VISCOSITY OF THE LOWER CRUST

2017 ◽  
Author(s):  
Greg Hirth ◽  
◽  
Mark Behn ◽  
William Shinevar
Keyword(s):  
Lower Crust ◽  
Shear Zones ◽  
Crustal Shear Zones

RELATIONSHIPS AMONG TRANSIENT BRITTLE AND DUCTILE DEFORMATION AND METAMORPHIC REACTIONS IN CRUSTAL SHEAR ZONES

2017 ◽  
Author(s):  
Kevin H. Mahan ◽  
◽  
Philippe Goncalves ◽  
Omero F. Orlandini ◽  
Thomas Leydier ◽  
...  
Keyword(s):  
Shear Zones ◽  
Ductile Deformation ◽  
Crustal Shear Zones

Using apatite to resolve the age and protoliths of mid-crustal shear zones: A case study from the Taxaquara Shear Zone, SE Brazil

Lithos ◽  
2020 ◽  
Vol 378-379 ◽  
pp. 105817
Author(s):  
B.V. Ribeiro ◽  
J.A. Mulder ◽  
F.M. Faleiros ◽  
C.L. Kirkland ◽  
P.A. Cawood ◽  
...  
Keyword(s):  
Shear Zone ◽  
Shear Zones ◽  
Se Brazil ◽  
Crustal Shear Zones
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