Day 7 of : back in the Torridon Group with sandy mudstones of the Clachtoll Formation at Clachtoll Bay, Sutherland, with desiccation cracks! The namesake of Clachtoll, the split rock (a' chlach thuill) can be seen in the last photo.

Day 6 of : Carboniferous (Marsdenian) Chatsworth Grit from Higger Tor, Peak District. Pictured also at the summit of Win Hill is the slightly older Kinderscout Grit (Kinderscoutian).

Day 4 of : Scourie amphibolite (L) and post-Laxfordian pegmatite (R), from the stunning road cutting on the A838 north of Laxford Bridge, Assynt. The Scourie dykes (2.4 Ga) cut the felsic gneiss (~3.0 Ga). These are then later cut by the pegmatite sheets (1.7 Ga).

The Applecross Fm overlies the Diabaig Fm, which preserves palaeovalleys in the Lewisian complex! So the Lewisian was at the surface, just as it is now, in the Neoproterozoic! Just in case you needed reminding of just how ancient the Lewisian is... Meanwhile, here's a picture of that ancient gneiss landscape.

Day 2 of : the unmistakable Applecross Formation: a coarse fluvial sandstone from the Neoproterozoic. This is what the famous Assynt hills like Suilven (pictured) and Quinag are made of!

Since we'll have no thin sections next term, I'm going to jump on the bandwagon...
First up is the Arran granite!
Pictured also is Goat Fell, taken from Brodick.

.1: Cordierite-chlorite schist, Trois Seigneurs, France. Inclusion-rich pretectonic cordierite has been fragmented by a second phase of deformation, and infilled with syntectonic muscovite, forming an en-echelon pattern.

: Granodiorite, Trois Seigneurs, France. This rock originally contained biotite, but it has been chloritised. Titanium cannot fit into chlorite, so it has been kicked out to form sphene (centered). Other visible minerals are plagioclase feldspar, potassium feldspar, quartz and epidote.

-005b: Garnet-chlorite schist, Sierra de los Filabres, Spain. Shows relict compositional layering, with garnet-rich layers and chlorite-rich layers.

The same kyanite granulite again, this time showing a kyanite grain that has been squished by a garnet. The distortion of the kyanite lattice is shown by the variation in extinction angle across the grain. This indicates that deformation continued after the rock reached its metamorphic peak.

#122091: Kyanite Granulite, Silesia, Poland. Dominated by quartz, the protolith of this rock was likely a psammite with small amounts of mud, allowing the formation of garnet and kyanite. Note the coarser-grained quartz stringers in the groundmass. These define the rock's foliation. Under intense deformation, the larger quartz grains have deformed by dislocation creep and recrystallised into smaller grains. This rock shows the process of mylonitization in action!

#120350: Core of metabasic granulite boudin, Halls Creek, Western Australia. These boudins were originally basic dykes cutting sediments (now amphibolite facies leucosome gneisses). The migmatisation of the gniess dehydrated the metabasite, allowing high-temperature granulite conditions to attained in the metabasite. The boudin margins were later rehydrated when the melt solidified. It is clear that the granulite transition did not go to completion in this rock, since hornblende can be seen.

: Lherzolite, Troodos Ophiolite.
This rock was once part of the lithospheric mantle.

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