CRUDE OIL EXTRACTION

A question often asked is what happens to all the empty spaces when billions of litres of crude oil is pumped out of the earth? To answer the question we need to understand how crude oil was formed.

Crude oil is also known as petroleum. The word petroleum literally means "rock oil" and is derived from the Latin words Petra (rock) and Oleum (oil). Wherever crude oil is found today the earth was covered with water millions of years ago. Crude oil and petroleum are called fossil fuels because they are mixtures of hydrocarbons that formed from the remains of animals and plants that lived millions of years ago in oceans, lakes, and swamps.

It all started 300 to 400 million years ago. Aquatic plants and animals (organic matter) died and dropped to the bottom and were covered by sand and sediment – Fig 1. With time more and more layers of sediment deposited on top of the plant and animal remains and formed porous rock – Fig 2. Over millions of years heat from inside the earth and pressure from the layers of sedimentary rock above turned the organic matter into crude oil and natural gas – Fig 3.

Today we drill down through the layers of sand and sedimentary rock to reach the porous rock formations that contain the oil and gas deposits. Contrary to what you may have believed up to now, extracting the crude oil is more like sucking liquid from a sponge with a straw than from a puddle of liquid.

Now back to the initial question. You may assume that gravel or tumbling rocks fill the void, but the truth is much simpler. The pressure underground is extremely high and as the oil and gas are removed, other matter will be forced in to replace it. Consequently underground water from the adjacent area moves in to take up the space that has been vacated.

If you have any questions about petroleum topics or the complete range of Q8 lubricants, simply phone 011 462 1829, email us at info@bcl.co.za or visit www.bcl.q8oils.co.za.