Oil shale geology is about how oil shale is formed. Oil shale is made from the remains of plants and animals from millions of years ago. When these plants and animals died, their remains were buried in the ground. Over time, the remains were buried even deeper and the pressure and heat from the Earth changed them. Eventually, these plant and animal remains became a type of rock called “oil shale”. Inside oil shale is a type of oil called “kerogen”. Kerogen is a liquid and it is the same type of stuff that is inside oil that comes out of the ground. To get this oil out, the oil shale rock needs to be heated and then the oil can be collected.