Most people know how important oil is to our daily lives and that its getting harder and harder to find. However, we spend little time thinking about where it comes from. We know that most of it comes from the middle east but not how it has developed over millions of years. Some people think oil comes from dinosaurs. There sure must have been a lot of dinosaurs over time if this were true. Most scientists believe that oil comes from very small creatures the size of a pinhead called diatoms. Diatoms aren't plants but they share one very important characteristic with plants. They take light from the sun and convert it to energy. Humans can't do this. Diatoms float in the top of the oceans and lakes where they can take in sunlight. Their skeletons are made of the same material as sand. Over time these tiny creatures settle to the bottom and eventually turn into oil. So, getting back to the dinosaurs, oil doesn't come from the largest creatures that ever existed but from one of the smallest.

After hundreds of thousands of years and millions of dead diatoms a thick organic sludge forms at the bottom of the oceans and seas. The sludge piles up on the floors of the ocean, particularly in nutrient-rich waters, and is eventually turned into solid rock. This sludgey ooze turns into source rock. Source rock is a rock rich in organic matter which when heated sufficiently will generate oil or gas. All the oil created by the source rock won't be useful unless it is being stored in an accessible container, a rock that has room to suck it up.

Oil migrates to what’s called reservoir rock which acts as a container and holds the oil underground. Reservoir rocks are porous. This means that these rocks have tiny holes through which the oil can flow. Oil can occur only in pores. Reservoir rock is also permeable iwhich means its pores are connected. Consequently, the oil can move out of its container (the reservoir rock). Sandstone is porous and permeable and has lots of room inside to trap the oil and is the most common reservoir rock.

Oil is not just sitting there in an underground cave. It is contained in this solid, reservoir rock which soaks up the oil. Oil does not accumulate into large quantities unless it is trapped in a particular place. The sandstone oftentimes lies beneath a dome-shaped or folded layer of some non-porous rock such as limestone. It can also be trapped at a break in the layers of the earths crust. Oil companies, such as Western Pipeline Corporation, are constantly searching for trapped oil in reservoir rock trapped underneath limestone or beneath layers of crust.

Bob Jent is the CEO of Western Pipeline Corporation.Western Pipeline Corp .specializes in identifying, acquiring and developing existing, producing reserves on behalf of its individual clients.