Question

How was Petroleum formed?

Answer 1

petroleum was formed from the remains of tiny organisms called plankton that were found in the bottom of seas and oceans. Plankton have tiny droplets of oil inside their bodies. As these organisms died, their bodies settled at the bottom of the sea or ocean and covered with layers of sand and clay. Over millions of years, due to absence of air, high pressure these dead organisms transformed into petroleum and natural gas.

Answer 2

$\textbf{Formation of Petroleum }$:

When remains of the dead organisms sank to the bottom of the sea, they get converted by sand and clay.

After millions of years under the combined effect of high temperature, high pressure and bacteria in the absence of air, petroleum forms.

The petroleum so formed passes through porous rocks untill it got trapped between some impervious rocks.