9781422285602

Chapter One HOW OIL FORMED

W hen you picture oil, you probably imagine a dark, thick, and gloppy substance. And oil can indeed look this way. But crude oil varies in its appearance. Depending on how it formed, and on the amounts of its various substances, it may be thin and runny, or it may be thick like molasses. It also varies in color from light brown to almost black. Despite these different forms, nearly all oil begins in the same way.

hydrocarbon: a substance containing only the pure chemical substances, or elements, carbon and hydrogen. kerogens: a variety of substances formed when once-living things decayed and broke down, on the “rock oil,” a natural liquid substance formed over a very long time within the Earth, from the remains of once-living things. porous: allowing a liquid to seep or soak through small holes and channels. Words to Understand way to becoming oil. petroleum: meaning

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