After completing your post graduation programme You can give Combined Geoscientist and Geologist examination conducted by UPSC every year. You can also apply for PSUs job after clearing GATE entrance exam. The oil companies become more viable for exploration and this creates a major demand for Geologists in the market.

The Public Sector you can apply:

Oil & Natural Gas Corporation Ltd. (ONGC)

National Hydro Power Corporation (NHPC)

National Thermal Power Corporation (NTPC) etc.

Good Luck!