Honest, it was only a guess based on what I'd just googled!
And if I could understand what the hell you were going on about in the second half of your post, I ight be able to respond to that, too!
Sorry ! It means Igneous and Metamorphic Petrology. A branch of geology dealing with the study of volcanic, plutonic and metamorphic rocks, as opposed to sedimentary rocks,
(which is often disdainfully referred to as 'gardening'. )
I knew a Geordie geologist who would say "Ig & Met Pet, pet".