Explanation of Why Natural Gas Is Found in the Formation - Research Paper Example

Module Job Search Plan Natural gas refers to the free existence of a hydrocarbon gas mixture in the environment. This gas mixture is mainly composed of methane gas. The gas exists in deep underground rock formations (Fjaer 369). Consequently, an example of a deep underground rock formation is the Marcellus Shale. Therefore, Marcellus Shale represents black, low-density, carbonaceous shale that occurs beneath the surface of the earth. This shale is rich in organic matter content. This is owed to the accumulation of sediments in the sea. Thus, the shale, whose formation dates back to millions of years, covers a long stretch on the Northeast to the Southwest shore. Consequently, the formation forms a crucial source of natural gas reservoirs. Thus natural gas extracted from these reservoirs would be used as a source of energy. THE EXTENT AND CHARACTER OF THE FORMATION Marcellus Shale, like other fossil fuel formations such as oil and coal, was essentially formed through decomposition of remains of plants and animals over a long spell of time. Natural gas could be formed through two processes which include the following: Thermogenic formation. This process refers to the formation of natural gas as a result of temperature and pressure changes in the Earth’s crust resulting in compression effects on the overlying debris. Biogenic formation. This process refers to the formation of natural gas as a result of action transformation of organic matter because of the effect of microorganisms. Consequently, Marcellus Shale formation was as a result of a thermogenic formation process. Thus, the shale is a geological formation that was formed as a result of accumulation of sediments in the sea. Consequently, organic matter (such as the remains of plants and animals) was compressed at extremely high pressures for a long time. This process resulted in the formation of thermogenic methane. The organic particles decomposed were covered in mud and other sediments. Consequently, the debris exerted pressure on the underlying organic matter. This cycle was carried on for long spells of time amounting to millions of years. Thus, with time, more and more sediments and debris was piled on the organic matter beneath the materials. This, in turn, continued to exert increased pressure on the organic matter. As a result, the organic matter was compressed. Consequently, the compression resulting from the overlying debris broke down the organic matter. This process was also aided by the existence of extremely high temperatures beneath the Earth’s crust (Victor, and Jaffe 26). Since the crust’s temperature increase with depth, at shallow deposits with low temperature, more oil was produced as opposed to natural gas. However, at deep deposits with extremely high temperatures, more natural gas was produced as opposed to oil. Therefore, Marcellus Shale extends throughout the Allegheny Plateau of the Northern America region. Thus, the shale runs through the regions of New York, Pennsylvania, Ohio, Maryland and Virginia. Its bedrock also extends to the western parts of New Jersey, Kentucky and Tennessee. In addition, its outcrops appear in central New York. Here, there exist two joints at right angles which make cracks in the formation. Consequently, this process results in the formation of vertical cliffs which when exposed appear black or gray in color. ESTIMATED NATURAL GAS RESERVES The process of extracting natural gas is extremely expensive; thus, there has to be substantial evidence of the economic viability prior to the commencing of the extraction process (Bell 670). Consequently, the following procedure helped in the determination of the nature of the Marcellus Shale natural gas reserves. Conventional and Unconventional Natural Gas. Convection natural gas refers to the existence of natural gas in trapped reservoirs beneath the Earth’s surface (Hyne 190). Consequently, this gas comprised the majority of natural gas reserve estimates. Those traces of natural gas estimates that do not exist in the traditional, conventional setting are referred to as unconventional. Natural Gas Resource Base. The natural gas resource base represented the entire volume of natural gas estimates (Zoback 18). This is because the estimate represents all the volume of natural gas trapped beneath the surface prior to extraction and production. Therefore, some of the natural gas estimates accounted for in this estimate existed in non-recoverable forms. Discovered and Undiscovered Technically Recoverable Resources. From the natural gas resource base, recoverable resources estimates were made. This was in line with the existence of the necessary technology for the extraction of recoverable resources exists. Consequently, the establishment of the location of these resources (as outlined in the extent of the Marcellus Shale formation) resulted in the resources being referred to as discovered resources. Therefore, the discovered resources included estimates of the natural gas to be extracted for commercial purposes. Economically Recoverable Resources. In addition to the establishment of whether or not the intended resources were recoverable, the resources had to be checked for their economical viability. Economical viability refers to the profitability of the natural reserves with respect to the prevailing market conditions. This implies that the reserves should be profitable enough to produce significant returns following the extraction process. Consequently, economically recoverable resources estimates stipulated the estimates for the economically viable natural gas reserves (Zoback 20). However, some factors may lead to the availability of the economically unrecoverable sources. For instance, the necessary technology minimizing their cost of extraction may be made available. In addition, market conditions may provide for the economical extraction of these resources. Proved Reserves. The natural resource estimates above were further broken down into different reserves. Consequently, proved reserves referred to the reserves that had geological and engineering proof of economical recoverability based on current economic conditions. This implied that there existed a high probability of economical returns from the extraction process of the proved reserves. Consequently, estimates of the proved reserves were obtained prior to the extraction process. These estimates were further classified into either nonproducing reserve estimates or producing reserve estimates. However, such estimates were arrived at after the commencement of the extraction process. Other Reserves. These included estimates of other forms of proved reserves. However, the quantity and other characteristics of these reserves remained unknown. Consequently, extraction of natural gas from such reserves was not fully assured. Therefore, with respect to the discovery of the Marcellus Shale formation, the estimates made included the following: Early Marcellus Shale Estimates. Initial estimates of natural gas contained in the shale formation were calculated to be 1.9 trillion cubic feet. These calculations were done by the United States Geological Survey. Therefore, these huge deposits of natural gas were estimated to be found in the extension of the Marcellus Shale formation. Hints of enormous production. The initial well drilled in Pennsylvania resulted in a promising flow of natural gas. The drilling process employed both directional drilling and hydraulic fracturing methods. Consequently, with time, over 300 gas wells have become operational in Pennsylvania. Other estimates. Although is was initially estimated that Marcellus Shale formation contained 1.9 trillion cubic feet of natural gas, further research carried out at the Pennsylvania State University revealed increased deposits. According to the study, the shale could contain more than 500 trillion cubic feet of natural gas. However, using the available technology of directional drilling and hydraulic fracturing, only 10 percent of the deposits can be extracted. EXPLANATION OF WHY NATURAL GAS IS FOUND IN THE FORMATION Natural gas occurs in the Marcellus Shale in three ways. Consequently, these ways include the following: Within the pore spaces of the shale Within vertical joints in the shale On mineral grains and organic material Therefore, a significant amount of the recoverable gas is contained in the pore spaces. Since the rock bases of the Marcellus Shale formation are impermeable, the natural gas formed remains trapped in the pore spaces (Charlez and Charles 43). However, these low permeability rate also accounts for the slow rate of production of natural gas within these wells. Nevertheless, intersection of some wells caused by fractures enables the natural gas formed to rise to the well bore levels. Consequently, these interactions caused by the fractures allow the wells to drain from a wide rock base. This, in turn, increases the productivity. THE PROCESSES OF HORIZONTAL DRILLING AND HYDRO-FRACKING Once sufficient evidence for the existence of proven natural gas reserves at Marcellus Shale formation was made, the extraction process commenced. Consequently, the drilling process employed directional, horizontal drilling and hydro-fracking processes (Wan 424). Directional Drilling. This refers to the vertical drilling into the Earth’s surface. However, the process is not highly effective in the stimulation of potential rock bases. Besides, the process also has numerous limitations, thus, necessitating the need for complementary methods of drilling. Horizontal Drilling and Hydro-fracking. This mode of drilling complemented directional drilling. Consequently, all vertical wells initially employed directional drilling. Thus, directional drilling occurred to a certain depth above the target rock. Once, the desired depth was achieved, a hydraulic motor was attached to the drilling bit and pipe. Consequently, the flow of the drilling mud powered the hydraulic motor. As a result of technological advancements, the drill bit rotates in the absence of the rotation of the pipe. This characteristic enables the bit to deviate from the alignment of the drill pipe (Wan 429). Consequently, horizontal drilling was achieved. This drilling process tracks the target rock. However, the drilling process requires a thorough understanding of the target rock. Thus, necessary instruments were employed in maintaining orientation of the drilling process. Therefore, owed to its complex nature, horizontal drilling is extremely expensive as compared to directional drilling. However, horizontal drilling results in numerous advantages. Consequently, some of the advantages resulting from horizontal drilling as opposed to directional drilling include the following: Hits targets that may not be reached by directional drilling. For instance, a reservoir may be located in an area that prohibits drilling. Thus, employment of horizontal drilling enables the drilling of such targets. For instance, the fractures and joints of the Marcellus Shale formation were vertical. Thus a vertical well would not optimize the number of joints intersected. Drains broad area from a single draining pad. This implies that, with the employment of horizontal drilling, numerous drilling pads need not necessarily be dug. Increases the “pay zone” within the intended rock. Horizontal drilling allows the extraction process to maximize on the capacity of the target rock to be drilled. This effect has resulted in the horizontal wells at the Marcellus Shale formation being some of the most productive gas wells. Improves the productivity of wells. In the case of a fractured reservoir, horizontal drilling aids in acquiring maximum number of intersection of fractures. This, in turn, boosts the productivity of the well. Helps in the installation of underground utilities in situations, where excavation may not be possible. ENVIRONMENTAL IMPACT AND POLITICS Any hydraulic drilling process would result in numerous environmental concerns. Consequently, these concerns have resulted in the politicization of the adequacy of regulatory measures with regards to hydraulic drilling. Thus, some of the environmental impact issues as a result of exploitation of the Marcellus Shale include the following: Ground water contamination Air pollution Mishandling of waste Air Pollution. The drilling process may result in the pollution of the air as a result of methane leakages as well as other emissions from the diesel powered engines. The leaked methane to the atmosphere decomposes to form carbon dioxide, thus contributing to the formation of greenhouse gases. Ground Water Contamination. Ground water within proximity to fracking wells has been found to contain high levels of methane. Consequently, contaminated ground water may not be suitable of human consumption. This could be owed to the health effects that accompany the consumption of contaminated water. Mishandling Of Waste. Waste water resulting from the extraction process may contain may contain impurities such as the spent fluids. In fact, this water may contain up to 70 percent of the waste fluids. This water may also contain hazardous chemicals that act as both water and air pollutants. Consequently, these chemicals could be harmful to the skin, respiratory system and the eyes. In addition, the hydraulic fracturing process may lead to the emission of harmful radioactive materials to the environment. POLITICS Air pollution resulting from emissions from natural gas plants has necessitated the employment of new regulations with regards to control of these emissions. Consequently the regulations are geared towards minimizing the air pollution resulting from these emissions. Other regulations by the EPA seek to control the contamination of ground water. For instance, the US Safe Drinking Water Act seeks to regulate water pollution in the nation. Therefore, this implies that governments are constantly coming up with regulations to try and combat the pollution resulting from the hydraulic fracturing process. Consequently, there exist numerous Legislations on the management of hydraulic drilling. In addition, a number of public information resources with regards to hydraulic drilling and the health hazards involved also exist. Moreover, opposition to fracking activities in various parts has resulted in the employment of various public relations measures by companies. These efforts are geared towards the demystification of the fracking activities and processes. Works Cited Bell, F. G. Geological Evidence. Basic Environmental and Engineering Geology. Caithness, Scotland: Whittles Pub. 2007. Print. Charlez, Philippe A., and Charles Fairhurst. Rock Permeability. Rock Mechanics Petroleum pplications. Paris: Editions Technip, 2007. Print. Fjaer, Erling. Rock Formation. Petroleum Related Rock Mechanics. Amsterdam: Elsevier, 2008. Print. Hyne, Norman J. Existence of Natural Gas. Dictionary of Petroleum Exploration, Drilling & Production. Tulsa, Okla.: PennWell Pub. Co., 2006. Print. Victor, David G., and Amy M. Jaffe. Historical Case Studies. Natural Gas and Geopolitics From 1970 to 2040. Cambridge: Cambridge University Press, 2006. Print. Wan, Renpu. Horizontal Drolling. Advanced well Completion Engineering. Waltham, MA: Gulf Professional Pub., 2011. Print. Zoback, Mark D. Natural Gas Existence. Reservoir Geomechanics. Cambridge: Cambridge University Press, 2007. Print. Read More