US shale oil deposits: Two trillion barrels of crude oil shale deposits.

By JERICAN for OIL-PRICE.NET, 2006/12/29

This may sound like a fiction story but it is true! While total world resources of oil shale are conservatively estimated at 2.6 trillion barrels, US sits on close to two trillion barrels of crude. Possibly more than all the crude than was ever produced worldwide since petroleum age began.

The Green River Shale Formation encompassing the States of Colorado, Utah and Wyoming was first discovered in 1924. This famous shale formation covers tens of thousands of square miles. It is found in three different ancient lake basins. The layers of sediment in this formation stretch undisturbed for many miles.

This shale is a soft sedimentary rock that readily fractures into layers, composed of minute particles of clay, which may easily be removed. It was formed from multi layers through erosion. There are 40 million layers in one part of this formation. Deposits within these layers are fossilized plant, animal life and algae, which has turned over millions of years into kerogen. Some claims have been made that this was formed from the Great Flood of Biblical times. Geologists say that this formation was formed through countless floods perhaps through 500 to 700 millions of years.

There are two conventional approaches to oil shale processing. In one, the shale is fractured and heated to obtain gases and liquids by wells. The second is by mining, transporting, and heating the shale to about 450oC, adding hydrogen to the resulting product, and disposing of and stabilizing the waste. Both processes use considerable water. The total energy and water requirements together with environmental and monetary costs have so far made production uneconomic. During the oil crisis of the 1970′s, major oil companies spent several billion dollars in various unsuccessful attempts to commercially extract shale oil.

After initial attempts proved to be too expensive and were shelved some ten years ago, a host of energy companies are revisiting technologies to successfully extract kerogen from shale and economically turn it into crude oil. Participating giant Shell Oil representative, Terry O’Cannon states, “We try to keep them from speculating too much and keep expectations low because we don’t know if this technology will be successful and viable in the long term.”

Seismic vibrators bounce soundwaves underground. The echo helps locate crude oil.

By STEVE AUSTIN for OIL-PRICE.NET, 2009/10/08

Many of us are aware of the value of oil and very aware of the oil price rise. Oil drills and oil exploration float to mind every time the oil prices go north. But are we aware of the process behind the hydrocarbon reaching the surface? Here it is:

It starts with a company obtaining licence to explore oil in a specified area which could be sea, land, forest or ice.The first thing the company strives to do is create a comprehensive picture of area above and below the oil. So, the first step is survey.The company may use Aerial survey: Aerial photographs and satellite pictures to get the data. Magnetic survey: establish the force of gravity. Seismic survey: detailed analysis of the underlying rocks using sound. Then the exploration process:

Shock waves are sent into the ground using vibrator trucks, and the time taken for the reflection of the sound is calculated using devices called geophones. Earlier dynamite charges were used in place of the vibrator trucks to collect the data, but the use has been banned for environmental reasons.

The data collected from the geophones called geophone data are converted into seismic lines by modern computers. These data are used by the geologist to create a 3-D computer model of the dynamics and geometries of the rocks below the earth. Geophysicist help interpret the seismic data to create a detailed picture of the under rock/undersea. Now the geologist and geophysics work together to establish the precise location of oil site to drill the holes.

After this comes the drill for oil. Drilling is a very expensive operation but is the best way to find oil. This is the stage when theory is put to practical test. The drill helps understand the composition of the rocks and the fluid present in the rocks. This information called well logs help data interpretation and the crucial decision of whether to continue the exploration or abandon it.

Even with all the modern tools, oil exploration has a high failure rate, and hence oil producers look to expand existing wells as it is more cost effective. But nothing beats the discovery of an oil rich well, luck favoured.

Next time you go to fill gas, you’ll know how it came to be there. Won’t you?