Explain why the Composition of the Plagioclase Feldspar may vary within an Intrusion.
Ca plagioclase forms early meaning that it settles down through the magma body and forms in the lower part of the intrusion and solidifies. Na rich plagioclase forms later so is only present in the middle and upper parts of the intrusion – the part of the intrusion which solidifies last.
AG
Related Geology A Level answers
All answers ▸What are the major components required for a oil accumulation to form.
Explain how pillow lavas are formed and describe how they can be used as a way up structure
During folding, how are joints formed in sandstone and cleavage formed in shale?
Describe how you can distinguish between intrusive and extrusive igneous rocks?