How old is natural gas?

Answer 1

Natural gas was formed from the remains of tiny sea animals and plants that died 200-400 million years ago.

When these tiny sea animals and plants died, they sank to the bottom of the ocean where they were buried by layers of sediment that hardened into rock. Over hundreds of millions of years these energy-rich carbon remains were buried deeper and deeper under layers of this sedimentary rock that became thousands of feet thick. The enormous pressure of the ocean and these layers of rock, the heat generated by that pressure and the heat of the Earth's core combined to transform this organic material into petroleum and natural gas.