Pondicherry

Absolutely, it will be Loyola because it has world wide recognition.

IPU is better than University of Pondicherry as it offers good placement.

Yes, you are eligible for M.Sc in applied geology.

No, now the CAT score is not required. You just have to clear the entrance exam.

Hi,
NRI seat at Pondicherry University is decided by MHRD and university authorities. One has to go directly and approach the authorities.
All the best.

All of them are under the same category. PU is a central university, hence it has slightly good ROI but their brand name might be limited to Tamil Nadu, Kerala and Bangalore. But remember, PSG, TSM, SSN AND PU have equal brand name within Tamil Nadu as of top B-schools like IMI, IMT or Fore. So, choose where you want to settle. If you aim for cities like Mumbai or Delhi, then go for bigger schools than these.