Deformation and metamorphism
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Picture 1a: Tourmaline-quartz aggregate, undeformed
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Undeformed spherical aggregate consisting of tourmaline, quartz, and feldspar in a 550-Ma-old granite (southern Menderes Massif, SW Turkey). Width of photograph is about 10cm.
Related Publications:
Hetzel R., Reischmann T. (1996). Intrusion age of Pan-African augen gneisses in the southern Menderes Massif and the age of cooling after Alpine ductile extensional deformation. Geological Magazine 133, 565-572.
Picture 1b: Tourmaline-quartz aggregate, deformed, X-Y section of strain ellipsoid
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Deformed tourmaline-quartz-feldspar aggregate (X-Y section) in a ductile shear zone (southern Menderes Massif, SW Turkey). For an undeformed aggregate see Picture 1a. Length of pencil is 13 cm.
Related Publications:
Hetzel R., Reischmann T. (1996). Intrusion age of Pan-African augen gneisses in the southern Menderes Massif and the age of cooling after Alpine ductile extensional deformation. Geological Magazine 133, 565-572.
Picture 1c: Tourmaline-quartz aggregate, deformed, X-Z section of strain ellipsoid
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Deformed tourmaline-quartz-feldspar aggregate (X-Z section) in a ductile shear zone (southern Menderes Massif, SW Turkey). For an undeformed aggregate see Picture 1a. Length of pencil is 13 cm.
Related Publications:
Hetzel R., Reischmann T. (1996). Intrusion age of Pan-African augen gneisses in the southern Menderes Massif and the age of cooling after Alpine ductile extensional deformation. Geological Magazine 133, 565-572.
Picture 2: Prograde reaction biotite to garnet
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Thin section photograph (plane-polarized light) of a metamorphosed granite. During prograde metamorphism magmatic biotite (brown) has been transformed to garnet (grey minerals with high "relief") along the rim. Width of photograph is about 1.5 mm.
Related Publications:
Hetzel R., Romer R.L., Candan O., Passchier C.W. (1998). Geology of the Bozdag area, central Menderes Massif, SW Turkey: Pan-African basement and Alpine deformation. Geologische Rundschau 87, 394-406.
Picture 3: Crenulation cleavage, Suvanyak Complex, Southern Urals, Russia
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Crenulation cleavage in lower greenschist facies metasediments. The long axis of the Swiss knife is parallel to the crenulation cleavage.
Related Publications:
Echtler H.P., Hetzel R. (1997). Main Uralian Thrust and Main Uralian Normal Fault: non-extensional Paleozoic high-P rock exhumation, oblique collision, and normal faulting in the Southern Urals. Terra Nova 9, 158-162.
Picture 4a: Eclogite-blueschist, Maksyutov Complex, Southern Urals, Russia
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Transition between eclogite consisting of red garnet and green omphacite (upper part of picture) and blueschist (lower part) in the Maksyutov Complex, Southern Urals. The blueschist is made up of blue amphibole, red garnet, and minor amounts of phengite and epidote. Both eclogite and blueschist formed during a single high-P/low-T metamorphic event. The contemporaneous formation of the two rock types during one metamorphic event is readily explained by their different bulk composition. Object for scale is 6 cm in diameter.
Related Publications:
Hetzel R., Echtler H.P., Seifert W., Schulte A.B., Ivanov K.S. (1998). Subduction- and exhumation-related fabrics in the Paleozoic high-P/low-T Maksyutov Complex, Antingan area, Southern Urals, Russia. Geological Society of America Bulletin 110, 916-930.
Picture 4b: Blueschist, Maksyutov Complex, Southern Urals, Russia
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Blueschist made up of blue amphibole, red garnet, and minor amounts of green omphacite and white mica (phengite) (Maksyutov Complex, Southern Urals).
Related Publications:
Hetzel R., Echtler H.P., Seifert W., Schulte A.B., Ivanov K.S. (1998). Subduction- and exhumation-related fabrics in the Paleozoic high-P/low-T Maksyutov Complex, Antingan area, Southern Urals, Russia. Geological Society of America Bulletin 110, 916-930.
Picture 5: Zoned alkali amphibole, Maksyutov Complex, Southern Urals, Russia
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Thin section of zoned alkali amphibole in a metapelite. The mineral zonation of the amphibole reflects the retrograde metamorphic evolution in the high-pressure Maksyutov Complex, Southern Urals. The light-blue core of the amphibole consists of glaucophane, the dark blue rim is composed of crossite.
Related Publications:
Hetzel R., Echtler H.P., Seifert W., Schulte A.B., Ivanov K.S. (1998). Subduction- and exhumation-related fabrics in the Paleozoic high-P/low-T Maksyutov Complex, Antingan area, Southern Urals, Russia. Geological Society of America Bulletin 110: 916-930.
Picture 6: Lawsonite pseudomorphs, Maksyutov Complex, Southern Urals, Russia
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Lawsonite pseudomorphs (white) in a meta-rodingite indicate a blueschist-facies metamorphic event (Maksyutov Complex, Southern Urals). During retrogression and fluid infiltration at greenschist facies conditions the lawsonite porphyroblasts were completely replaced by clinozoisite and muscovite.
Related Publications:
Hetzel R. (1999). Geology and geodynamic evolution of the high-P/low-T Maksyutov Complex, Southern Urals, Russia. Geologische Rundschau 87, 577-588.
Picture 7: Large-scale folds in Zilair flysch, Southern Urals, Russia
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Large-scale symmetric folds in the Zilair flysch, Southern Urals.
Related Publications:
D. Brown, P. Spadea, V. Puchkov, J. Alvarez-Marron, R. Herrington, A. Willner, R. Hetzel, Y. Gorozhanina (in press). Arc-continent collision in the Southern Urals. Earth Science Reviews.
Picture 8: Posttectonic granite, Middle Urals, Russia
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Post-tectonic granitoid cross-cutting the tectonic foliation of an intensely deformed amphibolite in the Middle Urals. Coin is 3 cm in diameter.
Related Publications:
Hetzel R., Romer R.L. (1999). U-Pb dating of the Verkniy Ufaley intrusion, Middle Urals, Russia: A minimum age for subduction and amphibolite facies overprint of the East European continental margin. Geological Magazine 136, 593-597.
Picture 9: Axial planar cleavage, Cadaques, E-Spain
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Axial planar cleavage in folded metasediments. The folded sedimentary layering (S0) is recognized owing to the differential weathering of the individual layers. The planar cleavage (S1) is oriented subvertical. Object for scale is 6 cm in diameter.
Picture 10: Folded pegmatite dyke, Cadaques, E-Spain
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Folded pegmatite dyke in dark metasediments.
Picture 11: Folded boudins, Cadaques, E-Spain
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Three folded quartz boudins (upper part of image) indicate two phases of deformation. A first phase has led to the boudinage of the quartz veins. During a subsequent deformation phase the boudins have been folded. Coin is 2.5 cm in diameter.
Picture 12: Sheath fold, Cadaques, E-Spain
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Small-scale sheath folds developed in quartz veins. Coin is 3 cm in diameter.
Picture 13: Offset quartz veins in foliated cataclasite, Menderes Massif, SW Turkey
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Two quartz veins, which are parallel to the horizontal foliation in a dark grey cataclasite, are offset by two normal faults (dipping to the left). Coin in central upper part of image is 2.5 cm in diameter.
Related Publications:
Hetzel R., Ring U., Akal C., Troesch M. (1995). Miocene NNE-directed extensional unroofing in the Menderes Massif, SW Turkey. Journal of the Geological Society of London 152, 639-654.
