Unconventional oil resources exploitation: A review

Unconventional crude oil sources are geographically extensive and include the tar sands of the Province of Alberta in Canada, the heavy oil belt of the Orinoco region of Venezuela and the oil shales of the United States, Brazil, India and Malagasy. High production costs and low oil prices have hitherto inhibited the inclusion of unconventional oil resources in the world oil resource figures. In the last decade, developing production technologies, coupled with the higher market value of oil, convert large quantities of unconventional oil into an effective resource. From the aspect of quantity and technological and economic recoverability are actually the most important tar sands. Tar sands can be recovered via surface mining or in-situ collection techniques. This is an up-stream part of exploitation process. Again, this is more expensive than lifting conventional petroleum, but for example, Canada's Athabasca (Alberta) Tar Sands is one example of unconventional reserve that can be economically recoverable with the largest surface mining machinery on the waste landscape with important local but also global environmental impacts. The similar technology of up-stream process concerns oil shales. The downstream part process of solid unconventional oil is an energetically difficult process of separation and refining with important increasing of additive carbon production and increasing of final product costs. In the region of Central Europe is estimated the mean volume of 168 million barrels of technically recoverable oil and natural gas liquids situated in Ordovician and Silurian age shales in the Polish-Ukrainian Foredeep basin of Poland.