I'm an English teacher and I can only guess the meaning, the same as you.
I suspect this is because:
a) fundamentals (in this context) is jargon from this field - oil production - and only people who work in this field use the word in this way and understan what they mean by it.
b) it's been written by a non-native speaker and is a poor translation from their L1
So, you need to either ask an oil industry expert (not an English teacher) what it means, or find a better translation from the original!