in the extraction process, oil sands production cost is relatively high and therefore investments in oil sands are quite sensitive to persistent changes in oil prices. Gas emissions into the air, water pollution, toxic tailing ponds and the chances of oil spills from pipelines in the oil producing areas are environmental concerns in tar sand processing (Miller 456).
According to Kuuskra( 3), shale is a close grained, sedimentary rock made up of mud from flakes of clay minerals and small particles of other materials, which is processed to produce natural gas and oil. Large deposits of shale are found in “United States, China, Argentina, Algeria, Canada, Mexico and Libya” (kuuskra 9).
Extraction process starts with identifying economically viable well areas. Then, horizontal drilling and hydraulic fracturing methods are used in the extraction process. In the hydraulic fracturing method, hydrocarbon in a shale formation is released by injecting water, chemicals and sand into a well. “Release of the hydrocarbon opens fractures in the rock allowing the natural gas to flow into the well”. (“exploration and extraction of shale” 10).
Use of both methods together enables economical extraction of the shale gas. Unfortunately, mining of shale leads to pollution of the environment through emission of toxic gases in the air and also a poses a great danger to aquatic life if poisonous materials leaks in to the