Firstly great that you are interested in the sector and know...

Firstly great that you are interested in the sector and know enough to talk drill cores, the likelihood of polymetallic orebodies, and the "science" of nearology!

You have however asked very very broad questions... completing a degree in geology will start to answer them.

In the mean time start reading - http://www.goodreads.com/book/show/25014.The_Map_That_Changed_the_World - is about creating the first geological maps of the UK. You should gain some geological insight from the book which will enable you to refine your research.