Introduction
Shale rock, is a sedimentary rock composed of mixture flakes of clay and silt sized other mineral. Process of shale formation is called compaction. Shale oil, is an unconventional oil.it is produced by various processes like thermal dissolution, hydrogenation etc. Shale gas, is natural gas that is extracted from shale formations. China is estimated to have the world's largest shale gas reserves.
Clustering: Cluster placement should be matched to reservoir quality
Single clustering: gas production is reduced significantly when the cluster spacing is single the width growth of fracture is strongly inhibited due to mechanical interaction
Multiple clustering: multiple cluster perforation are typically used to create multiple fractures in any single stage placing these perforation is critical issue cause the number of perforation cluster to be used and the space between them significantly impact how effective the fracture can be created in the formation
Production using perforation cluster:
Perforation cluster productivity is determined by running production logs into horizontal wells. If multiple fluid phases are present then more sophisticated PLs are required that can differentiate the segregated fluids flowing in the well. Fiber Optic systems can also be deployed and monitored for extended periods of time to see how production can change along the lateral with time. Productivity from each perforation cluster can also be modeled using reservoir simulators. This requires knowledge of the petro physical properties of the shale and also the effectiveness of the completion. The latter can be modeled via hydraulic fracturing simulators.
Multi-stage hydraulic fracture
In this technique the shale rock is fractured by pressuri...
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... 60 years is 41.7% for Case 3 and for Case 4 it is found to be 38.9%.
Fig. 3 Comparison of Case 3 and Case 4.
Fig. 3 Explanation:
In the above graph it can be seen that the Y-axis is over the gas production rate and is taken in Mscf/D units. On the X-axis we take the time, and the unit or scale taken is by days. The dotted line represent the gas-production rate and the non-breaking line denotes the cumulative gas production. The Purple line denotes the Case 3 and Blue line denotes the Case 4.
Conclusion
By the following statistics we can derive the following conclusion that increasing the number of perforation clusters in one stage does not necessarily increase the initial gas rate and the cumulative gas production because the width growth of center and sub-center fractures is inhibited under certain fracture spacing and geo-mechanical properties of the reservoir.
Gas in shale formations are“low in permeability,” making it very tedious to extract, but with the increase in technological knowledge in fracking and horizontally drilling into shale beds, the vast reserves of natural gas resource could be extracted (4). Fracking is a large industrial operation that boost the “productivity of a oil or gas well” (5). It is a process by which, under very high pressure, a mixture of water, chemicals, and sand, are pumped into shale formations that causes fractures in the rocks to open wider or create new fractures that would allow otherwise trapped oil and gas to flow into the wells (6).
...ne gas fracturing, also known as gas fracking, have taken the majority of the dangers out of traditional fracking. Gas fracking is achieved by creating a gel made of propane mixed with the traditional fracturing chemicals that is injected into the well; afterwards, the gel turns into a vapor due to heat and pressure bringing only natural gas for collection (Nearing). Leaving water out of the drilling process keeps radioactive material, salt, and drilling chemicals from surfacing and possibly polluting water tables and surface soil. Using gas fracking also has the added benefit of using only twenty-five percent the amount of truck trips cutting down further emissions and oil usage. The issue with methane leakage is easily contained with proper concrete and steel piping to trap latent leaks and should never happen if wells are correctly constructed and serviced.
...a producing well is significantly lower than at other areas where no well is drilled. The driving force could be either natural or created by engineering design involving fluid injection through certain wells placed optimally to achieve the best results. Experimental data suggests that reservoir rocks are abundantly permeable in both vertical and horizontal directions. Among a myriad of factors related to geological and geochemical processes, the permeability of a rock is influenced by the slit, shape, configuration, and connectivity or a porous network.
One of the biggest natural resources used in fracking is water. On average, around one to eight million gallons of water are used on a fracture job. There are also around 500,000 active fracture sites around the world and each site can be fractured around 18 times. This means that roughly 72 trill...
...ydraulic fracturing. During Hydraulic fracturing, or fracking, holes are drilled into shale rock formations, deep beneath the earth's surface and injected with more than a million gallons of pressurized fracking fluid. This process creates small fissures within the rock layers that are held open by the sand particles, allowing the natural gas to vacate from the well (10). However, there is much debate over the long-term vitality and validity of the use of unconventional gas as a solution to the United States dependency on foreign oil. Much of this debate stems from what some have coined as the "exploration treadmill", the rate at which new plays must be added to production, in order to maintain a flat line and or growing (carbon)
Shale gas is a kind of unconventional nature gas, which is trapped or gathered in the dark shale or carbon rock. The rock layer has low permeability and low porosity, which means that the best way to get this recourse is fracturing to enhance connectivity and porosity. The shale gas reservoirs are mainly located in North America, Central Asia, China, Latin America, Middle East, North Africa and Russia and other countries and regions. The United State and Canada are only two countries, which have significant shale gas production.
Hydraulic fracturing, or “fracking,” involves injecting massive amounts of water, chemicals, sand and other material under high pressure into shale formations to break the rock and release the gas trapped inside (McGlynn, D., 2011).
America is facing an energy revolution. The shift from traditional energy sources such as coal and oil are fading while newer sources are being used to sustain an insatiable thirst for energy. A front-runner is natural gas, a cleanly burning and abundant alternative for conventional energy sources. This nonrenewable resource is found miles underground in prehistoric shale deposits, to show the magnitude “North America has approximately 4.2 quadrillion (4,244 trillion) cubic feet of recoverable natural gas that would supply 175 years worth of natural gas at current consumption rates” locked in these shale deposits (Loris). However, the dilemma comes from how natural gas is extracted from the earth. One of the processes of accessing the natural gas is called Hydraulic Fracturing or “Fracking”. It is the process of shooting a highly pressurized mixture of water, sand, and chemicals into cracks in the shale deposits, essentially fracturing the shale that then releases the natural gas (Malakoff).
Hydraulic fracturing, or fracking, is the process of extracting natural gas from deep in the ground. This method requires a company, usually an oil company, to drill deep into the earth’s crust and into the beds of shale, and then drill horizontally. Water, along with sand and other toxic chemicals, are then pumped into the shale rock to fracture it and letting all the natural gas that is trapped in the rock to flow up to the surface where most of it can be collected (McGlynn 1055).
The process of Hydraulic Fracturing is a process that 90% of natural gas wells in the United States use to extract gas from the ground. The first step in fracturing is digging anywhere straight into the ground Fractures are created by pumping large amounts of fluids at high pressure down a wellbore and into the rock formation. Hydraulic fracturing fluid commonly consists of water, proppant and chemical additives that open and enlarge fractures within the rock formation. These fractures can extend several hundred feet away from the well. The proppants - sand, ceramic pellets or other small incompressible particles - hold open the newly created fractures.
Hydraulic fracking is an extraction technique used to uptake natural gas in a deep gas well drilling (Brown et al., 2007). Rocks are fractured by a pressurized liquid which is typically a mix of water, s...
Hydraulic fracturing, which is the process of natural gas extraction, has been in debate for the past few years. It was first introduced back in the late 1900s, as a beneficial way to obtain clean fuel, and it also benefitted the economy by providing employment for many. However, recent studies have shown that hydraulic fracturing is causin...
The number of wells fracked grew significantly, reached 3000 wells per month by the mid 1950s. During the 1970s, there was a huge proliferation of massive hydraulic fracturing, resulted in an enormous number of wells that were stimulated by fracking. By the late 1970s, the process was widely used all different countries and religions, including Canada, Germany, Netherlands and England. It was not until 1999 that scientists found a new method to apply high pressure fluids to rubblize hard-rock formations and extract oil and gas trapped inside. Also, with the invention and application of horizontal drilling to fracking, it became possible to extract larger amounts of oil and natural gas from fracking shales. This absolutely has brought a revolution for the oil and gas industry of the U.S and changed the U.S energy picture from scarcity to abundance. Producers and drillers are now able to exploit a huge amount of natural gas and oil that were locked away in shells and hard rock formations previously. According to many credible reports, about 90 percent of today’s producing wells are stimulated by fracking; up to 35 percent of U.S natural gas production is from shale gas, compares with only 2 percent ten
In the last decade the extraction of natural gas from underground reservoirs has increased. Natural gas supplies 24% of the United States energy demand and is only expected to grow. Shale gas is natural gas that is found trapped in shale. Shale is sedimentary rocks that consist of clay minerals that have low permeability. Natural gas that is found in shale is buried in fractures below ground and must be extracted by hydraulic fracturing, also known as fracking [10]. One of the most recognized sites for the extraction of natural gas by fracking has been at the Barnett shale in the last decade. The Barnett shale is a region that extends west of Fort Worth, Texas to the Permian Basin and has been known to extend as far south into Mexico. The Barnett shale is a complex system of fractures in which the region has seen new developments in fracking to extract the natural gas from the ground [11].
Morphological characterization was carried out via SEM analysis. The micrographs of fractured surfaces of samples P-0.1D-1PO are represented in Figure 2. Figures 2 (a) and 2 (c) are related to the SEM images while figures 2 (b) and 2 (d) are the element mapping images. Moreover, figures 2 (a) and (b) demonstrate the samples before the crosslinking process and figures 2 (c) and (d) are attributed to the samples after the