Canisp Shear Zone 14/06/2002—11/10/2013

Rocks from the Canisp Shear Zone at Achmelvich, Assynt field course sample set. This is an example of a deep crustal shear zone in which the rocks have been modified by static recrystallization after they experienced heterogeneous high-strain deformation.
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S99-6 Amphibolitised Scourie Dyke Sample S99-6, plane-polarised light, field of view 4 mm. Scourie dyke from the headland N of the main beach, outside the shear zone. Originally a gabbronorite,...
S99-6 Amphibolitised Scourie Dyke
S99-6 Amphibolitised Scourie Dyke Sample S99-6, scanned slide, field of view 1.5 cm. At this scale you can see stronger hints of the igneous texture with hornblende replacing pyroxene, sphene...
S99-6 Amphibolitised Scourie Dyke
S99-7 Sheared Scourie dyke Sample S99-7, whole-slide scan, field of view almost 3 cm. This sample shows heterogeneous deformation, being a section across the edge of one of the set of...
S99-7 Sheared Scourie dyke
S99-7 Sheared Scourie dyke Sample S99-7, plane polarised light, field of view 3mm. This view is from the coarser domain in the section. In the lower part of the field of view, spongy...
S99-7 Sheared Scourie dyke
S99-7 Sheared Scourie dyke Sample S99-7, plane polarised light, field of view 3mm. From the opposite end of the same thin section as the previous slide, i.e. about 2cm away. The rock is...
S99-7 Sheared Scourie dyke
S99-7 Sheared Scourie dyke Sample S99-7, crossed polars, field of view 3mm. Same as previous view - strongly foliated amphibolite from the high-strain part of the specimen.
S99-7 Sheared Scourie dyke
S99-8 Tonalitic gneiss Sample S99-8, plane-polarised light, field of view 4 mm. Coarse poikiloblastic blue-green hornblende prisms grow over and at varying angles to the finer-grained...
S99-8 Tonalitic gneiss
S99-8 Tonalitic gneiss Sample S99-8, crossed polars, field of view 4 mm. Same view, showing the fine-grained granoblastic-polygonal matrix dominated by plagioclase.
S99-8 Tonalitic gneiss
S99-8 Tonalitic gneiss Sample S99-8, scanned slide, field of view 1.5 cm. An overview of the rock texture.
S99-8 Tonalitic gneiss
S05-1 Tonalitic gneiss Sample S05-1, plane-polarised light, field of view 4 mm. View from another tonalitic gneiss, showing hornblende poikiloblasts arranged in bands but showing...
S05-1 Tonalitic gneiss