In reply to themountaintamer: They may want you to simply give the main type of rock in the simplest form of which there are only 3, then an example
So
Igneous, Sedimentary, Metamorphic
therefore Lakes Volcanic eg Borrowdale Volcanic
North Yorks Moors Sedimentary eg Ravenscar Sandstone
as stated the areas mentioned often have multiple types of volcanic rock or mixes of the basic types
on my ML the home paper was used as a method of bringing out views and to give the assessor some idea that you know something (not everything) about the areas you would be doing ml work in.
Definately say Gabbro for the volcanic rock on Skye as someone else said tho