Title strip


The banding becomes thicker
We are now further into the heart of the dome and are looking at rocks which were buried even deeper and subjected to higher temperatures and pressures.. Many of the stripes are now thicker with a more pronounced contrast in darkness and lightness and with sharper edges.

The range of metamorphic grades
All these features indicate that compositional segregation has progressed to a higher degree. The composition of the rocks is similar to the last two locations, with feldspathic leucosomatic (light coloured) granitic bands alternating with thin bands of biotite.

Close up of gneiss

Close up of the high grade gneiss
Banded gneiss
Broad bands of dark and light rock are typical of higher grade gneiss
Controls on metamorphic grades
The amount of pressure and the temperature reached (called the grade of metamorphism) controls the degree of change in the rock. A higher amount of recrystallization, with coarser textures and more pronounced and wider banding reflecting higher grades. There are some areas where partial melting has taken place with a return to granite, a process of anatexis

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