How do we find oil?

Getting the oil

How do we find oil?

Geologists analysing a map.

Occasionally underground oil seeps to the surface. Then it is easy to find. However, most oil is buried underground.

We have to drill through the rock to get it. Early rigs could only work on land. However, we can now use oil platforms to get oil out from under the sea bed.

These geologists are looking for oil. They use charts of rock layers called seismic surveys.

When they find places that might hold oil, they send out a drilling team to test the site.

Oil is trapped in layers of rocks. Geologists can find the oil by looking for the tell-tale shapes of rock layers. However, these rock layers are underground. So they have to use special ways of 'seeing' the rocks.

Special ships look for oil fields under the sea. They use sound waves to build up a picture of the rock layers. This is called a seismic survey.

The only way to be sure if there is oil is to drill down into the rock.

This ship is making a chart of rock layers under the sea bed. This chart is called a seismic survey.

The chart is made using sound waves. The sound is produced by air guns towed behind the ship.

The sound is reflected of the bottom and picked up by special microphones - you can see them in the picture.

A survey ship towing sensors.