How was crude oil formed?
Adjacent seas were covered by shallow oceans. Over a period of millions of years the remains of marine animals and plants fell to the sea floor, they accumulated into thick layers and eventually were covered by layers of sand and silt. Over time, the immense weight of all of these layers compressed the lower layers into sedimentary rock. Bacterial actions, heat, and pressure converted the remains of the animals and plants into oil….. Oil is found under ground.
