Hydro-fracking is used to refer to the technique of propagating or fracturing the underground rock layer. This is done to search for petroleum, natural gas or other fossil fuels. This technique is also called fracturing. This kind of propagation is caused by the strong hydraulic pressure of some pressurized fluids that need an exit. According to Charles Pilippe A. (1997), the first hydro-fracking activity was carried out in 1947 in Hugoton gas fields in Southwest Kansas. There, this technique was used to get petroleum, natural gas, and coal seam gas.
Hydro-fracking takes place when the effective stress is reduced by the fluid pressure with a source rock to such an extent that the minimum principal stress becomes tensile exceeding the tensile strength of the rock material. Fractures that are formed this way will be perpendicularly oriented to the minimum principal stress. It is for this reason that this type of fractures (hydraulic fractures) is used to determine the stress orientation. Filled fractures orientations are used to infer the past orientation.
There are two types of hydro-fracking, which are induced and natural types. The two types differ from each other in that the induced type is artificial, thus it requires some human efforts, while the other type is natural as its name suggests. This type of fracking leads to the formation of dikes and veins. Veins are formed through repeated hydraulic fracking in the past leading to high porous fluids piling up. This can be seen in the case of crack-seal veins. In this case, the vein materials are deposited to accumulate according to each individual fracturing event. This is caused by seismic activities. In this case, fracturing comes as a result of pressurized hydraulic fluid in its search for an exit point. The fluid gets through the weakest point of the rock. It forces itself. Dikes are formed from the deposition of magma that appears underground due to increased pressure. The magma finds a way through the earth's crust. On reaching the ground, it accumulates and piles up according to every individual fracturing event. This type of fracturing can force oils and gases to shift from their main sources to the reservoirs, thus making their mining easier. The process of petroleum mining is further made easier when the pressurized fluid injects a lot of energy, thus leading to the creation of some new underground channels that collect all fossil fuels together.
Induced hydro-fracking is mainly used when people are in search of petroleum, natural gases, and other fossil fuel. This requires people to physically drill through the rock layer in order to reach the petroleum reservoirs. Hydraulic fracking is of great help to people. Some of the major areas where this hydraulic fracking is applied include the extraction of natural gas; moreover, the process of gas extraction is made easier.
It is also used in the measurement of the stress orientation. This is usually very important, as it is very helpful in the study of the earth's crust. This makes it possible for scientists to determine the frequency and likeliness of the occurrence of earthquakes that are caused by seismic waves. Therefore, it is very necessary to study the hydraulic forces that lead to the fracturing of rocks.
The heat generated from this activity is usually very important since it can be trapped to be used in the generation of electricity. This is done at the geothermal sites, where underground heat is used to heat the water that turns a turbine that generates geothermal electricity. The other very important application of this process is in the disposal of some wastes. These wastes are deposited underground through the shafts or vents dug during the process of hydraulic fracking.
However, hydraulic fracking also has some problems associated with it. Some of these problems affect people either directly or indirectly. The problems associated with hydraulic fracking also include environmental effects. This is the area that is mostly affected; the most grievous problem is contamination of underground water. As this process happens, the underground water is mixed with some chemicals that are harmful to the environment. For example, it has been noted that water wells that are situated near hydraulic fracking sites have seventeen times more methane, which is a chemical that is harmful to humans. This poses a great threat to human and animal lives.
This process also creates some risks to the air around the hydraulic site fields. As this process takes place, there appear some harmful gases when inhaled. It has also been proved to result in some health problems. One of the main health complications associated with hydraulic fracking includes cancer. Health agencies that are concerned with the fight against cancer have come out aggressively against hydraulic fracking. They argue that the long-term use of the induced process beats the very logic of scientific fight against the world's major killer disease. Preparing rocks for caving gives rise to underground holes which may cause a great hazard to heavy buildings on the earth's surface. Firms associated with these undertakings take little or no action to minimize the effects of such a scenario.
Today, with the improved technology, it is possible to monitor the occurrence of the hydro-fracking process through the injection of radioactive tracers. These tracers are used to determine the location and profile of a fracture that is created through the hydraulic fracturing process. Also, these tracers are used in the micro-seismic monitoring that estimates the size and the orientation of hydraulic induced fractures. This kind of monitoring is carried out through the placement of geophones in wellbores that are situated nearby.
While many geologists do not refute the adverse effects of hydro-fracking, what they insist on is the cost benefit analysis of the whole invention. They emphasize the importance of extensive research aimed at scientific improvement of the system in an attempt to eliminate the adverse effects of hydrofracking.