The first thing that you need to know about the article “Elastic wave velocity evolution of shales deformed under uppermost crustal conditions” is that the tests that were ran were triaxial tests on a series of sample Tournemire shale. A triaxial test is tests the strength of a rock, and that is was the goal of the experiment, to find the strength of the Tournemire shales. This is so important to see the way erosion has effect these shales when they are all in the same area, but they have different orientation bedding. The orientation bedding is anywhere from 0 degrees to 90 degrees, think of 0 degrees as shale that is lying parallel with the ground, while 90 degrees is the other extreme when the shale is perpendicular to the group, both are …show more content…
This will show if there is a major difference between different bedding with how strong the shale is, or, in other words, how eroded it. The pressures that were used during this experiment were 2.5 to 85 MPa, and at strain rates of 3 x 10-7 s-1 to 3 x 10-5 s-1. All these are saying is that there was a variation of pressions and compressions that were put on the shales in order to find when they begin to give and break apart or deform. Another major part of the experiment was that P and S wave elastic velocities were continuously measured with the different orientations with the respect of the bedding and what the maximum compression stress the shale could handle, this is the triaxial portion of the experiment I explained earlier. The reason that the scientists implemented the measurement of the P and S elastic velocities is because it allowed them to really pinpoint the presence of the plastic mechanisms, like mineral reorientation during the deformation of shale. This idea highlighted the fact that some shale has changed (reoriented) and this makes it …show more content…
Anisotropy is the idea that the rocks properties vary with direction, so it is very important in which way that the rock was oriented compared to the load, or the compression, that is applied to the rock. This means that orientation of the bedding that varied between 0 degrees and 90 degrees was very important. The scientists used Thomsen’s parameters to quantify the elastic anisotropy. A few ways that the scientist recognized this was that when brittle shale was preceded by a change in the P wave anisotropy. This was because of the crack growth and mineral reorientation that was discussed earlier. Next, anisotropy variations were the largest for the shale that was deformed perpendicular to the bedding, so when the bedding angle was closer to 90 degrees. When the confining pressures were at the highest, the anisotropy variations were the largest, which makes a lot of sense when we know that the anisotropy is the idea that the properties of rocks vary with different orientation and it created anisotropy reversal at high confining pressures. The last information the scientists found was that the P wave anisotropy change was weak when the shale deformed parallel to the bedding, and this is because it could not take a lot of pressure because of the way it was
On the first side of the outcrop the rock when examined was greenish and had small black grains indicative of diorite with hornblende giving the green color. The rock was similar to the outcrop encountered at Hollow rock which also had several fractures parallel although not as many, and that outcrop was also highly weathered. On the other side of the outcrop, the rock was incredibly different. This side was not weathered beyond recognition but
One of the major things noticeable from the cross section is that quite a few of the rock layers are over turned, where the older rock layers are above the newer rock layers. This is seen in the contact between the Quartz Monzonite of Papoose Flat and the Campito Formation which is also a disconformity. Next there is some fault zones separating the Camptio, Poleta, and Harkless formations. We then see some more overturned layers with the contacts between Saline Spring Valley Formation (lower and upper members) above the Mule Spring Formation along with some inferred folding. With a normal fault separating the inferred folding event, we see where the overturning occurs. In between the Cambrian layers we see Tertiary Basalt nonconformities also being folded, thus with that we know that the folding event was more recent than the formation of the Basalt. Next there is a large Basalt field with a spot of the Harkless formation. Again we see over tuning as the Basalt field ends there are the Devonian and Mississippian rock Layers on top of the basalt. Separating these overturned layers from the Harkless Formation and the Saline valley Formation (upper member), which are not overturned, is a thrust fault. From this information, there was a major stress event sometime after the Tertiary period causing the rock layers to fold and overturn. And from this stress event and from the folding, normal and thrust faults are formed. Finally we see that there were alluvial and landslide deposits from the Quaternary after the folding, faulting, and over
This newly exposed rock already had small cracks - weathering and erosion took full advantage of these. Water would creep in and the freeze - thus expanding. This expansion would create more cracks. Wind and water eroded by carrying away particles from cracks like these, as well as from the surface of the rock and any other nooks. Not only did water wash particles away - it also softened the rock which made erosion easier.
With our observation of the Shawangunk formation, we see a sedimentary rock formation containing a range of grain size. Such sizes range from pebbles (3cm-5cm), fine-grain sand, and medium-grain sand. There is some grading towards the bottom left of the outcrop known as a reverse grading with some small cross beds present (Figure 2). The grading occurs towards a slight part of the outcrop where we see the grading beginning as fine grain sediments and working up to coarser grain. With moderate sorting we see variations of degree of sorting per bed. As the degree of sorting varies as does the sphericity. The sediment bedding is well seen ranging in sizes of +/--20 cm to 40 cm. This outcrop has thick beds as one can see the basic units with cracks in between each (Figure 3). With mostly tabular beds consisting of sub-angular, and sub-rounded sediments, this outcrop also consists of some ventricular beds (Figure 4). When looking at figure 4, we have a small space of a ventricular bed present. This is because the bed comes in, pinches thicker bedding,
Based off of MICP data collected from core (Figure 19), the Pronghorn siltstone has a permeability on par with the upper and lower Bakken shales. The lack of permeability is supported by lithological analysis indicating a clay content of up to 50 % (Figure 20) across the Painted Woods asset. The low permeability and high clay content shows that the Pronghorn does have the potential to occlude primary migration of hydrocarbons from the lower Bakken shale into the underlying upper Three Forks. However, this only has a minimal effect on the overall potential of the upper Three Forks as a whole.
In my section of Out of This Furnace, it all begins with a walk amongst two brothers deep in a forest. The two siblings, Johnny and Mikie Dobrejcak, were inspecting the ruins of an old sawmill while on their walk. Before, they were probably at work and just wanted to spend quality time together after a long and busy day. While on the walk, Johnny asked Mikie if he could call him “Dobie” from then on, because all of his friends at the shop he works at call him by that name.
The land rose up and created a precipitous eastern edge of the batholith and a gentle western edge. 10 million years ago, uplift, which is the vertical rise of Earth’s surface due to natural causes, started to occur and accelerated quickly. Soon, the Sierra Nevada Mountain Range that we know today towered 14,000 feet in elevation. Throughout uplift, cracks formed in the granite of the mountains. They formed due to the pressure that came with the uplift. The erosion that stripped away most of the overlying rocks caused the remaining rock to expand and crack. These cracks are still forming today and they provide a template for future erosion.
The Freeman-Jewett shale formation is a strong indicator of a low-energy/quiet depositional environment. It is likely this layer was originally deposited offshore in a marine environment. This is further supported by the following Bena Gravel formation, which is emblematic of a transitional beach-type environment with pebble size sand and gravel. This coarser layer of sand and gravel overlying the silty and sandy shale could be evidence for a regressive cycle and receding sea levels. The Bena Gravel formation is eroded by Kern River Gravel which creates a disconformity in the stratigraphy. The Kern River Gravel has stream like deposits but since it cuts through the Bena Gravel Formation it is suggestive the Kern River Gravel formation has a delta depositional environment. The Terrace formation suggests a stream depositional environment. If terracing is present, it indicates a decrease in discharge over time. The next formation, Alluvium, is evidence of an alluvial fan deposition, a glacial deposition that has been reworked by meltwater, or of a dried lake bed. (Levin p.86). Regardless of which, the Alluvium formation gives away easily to mass wasting to from the landslide formation.
What is Marcellus Shale? It is a marine sedimentary rock buried thousands of feet beneath the earths surfaces. Sedimentary rock is one of the three main rock groups and is formed in four main ways: by the deposition of the weathered remains of other rocks; by the accumulation and the consolidation of sediments; by the deposition of the results of biogenic activity; and by precipitation from solution. Marcellus Shale is found throughout the Allegheny Plateau region of the northern Appalachian basin of North America. It stretches from upstate New York south through Pennsylvania to West Virginia and west to parts of Ohio. Marcellus shale was named after a town in upstate New York, the rock itself is millions of years old, formed from mud and other natural materials. Its made up of the formation of black shale that may contain lime stone beds and concentrations of iron pyrite and siderite. The Sedimentary beds and structure is very well developed. Lighter colored shales in the upper portion of the formation tend to split into small thin edged fragments after exposure. The fragments may have and leave rust stains from exposure of pyrite to air, and tiny gypsum crystals from the reaction between both of the fragments pyrite and the limestone particles. Fresh exposures of the pyriteiferous shale may develop the secondary mineralization of orange limonite and the pale yellow efflorescence or bloom of sulfur, associated with acid
Paragraph 1: Hydraulic fracking is a hot topic across the state of Texas. There are debates whether fracking is the actual cause of the sudden earthquakes in Texas. Fracking is an intense process where natural gas is extracted deep from within the earth. Drillers from oil and gas companies use a horizontal drilling technique that is initiated as a vertical casing and then makes a 90 degree turn. This allows the well to follow the natural fractures of shale rock. A fracking fluid mixed of water, sand, and chemicals is injected with high-pressure down the well. The fluid produces several small cracks in the shale, creating a pathway for the gas to enter and flow out of the well casing. Each well can
began to flow along weak layers that define the folds and faults and carved the resistant
The Kaibab Limestone is found at top elevations. Limestone is usually found on sea floors, so this to me could mean a transgression.Youngest rock layers are usally laid last and the oldest layers are laid first. This is what they call the principle of superpositioning. Because the layers of rocks are horizontal this follows the principle of original horizontality. Some of the layers on the Colorado plateau are tilted. The tilting of the rock layers created a plateau for the creation of the Colorado river. There is thought to have been some sort of geologic event happen here such as a fault. A fault happens when tectonic plates move as a transform, divergent, convergent boundaries, and either cause a strike slip, normal or reverse fault. Often when this happens there will be brittle deformation of the rocks but because there was no significant alteration of the rocks, questions still arise as to how it actually
The End of the Tour directed by James Ponsoldt follows the story of an interview done by David Lipsky about David Wallace. The all the scenes in this movie are very intimate and give the feeling that they viewer is right there as a fly on the wall. This feeling is very important for this movie because David Wallace is a very private and socially awkward person. These scenes reflect his preference of social settings in his famous and private life. A quote from the movie that contains the essence of the film is when Wallace tells Lipsky that he doesn’t want to be like him. It is clear that Lipsky looks up to Wallace and at one point in the movie forces Wallace to face his biggest fear that he has not lived up to the world’s expectations.
There are several types of shale that are drilled in which include: Bakken shale, Barnett shale, Eagle Ford shale, Haynesville shale, Marcellus shale, and Utica shale. Bakken shale is a formation of oil deposits that can be found in parts of Montana, North Dakota, and parts of Saskatchewan which is located in Canada (“What is Fracking”). Barnett shale contains large amounts of natural gas, and sometimes oil and can be found in North Texas (“What is
Lubna Warawra’s “The Departure-The Arrival,” and Nila Somaia-Carten’s “February 1, 1992,” from When Your Voice Tastes Like Home: Immigrant Women Write, are short stories written in first-person that describe the author’s journey immigrating to Canada. The women face many challenges immigrating, such as the pain of leaving behind their families, and loved ones. Warawra writes about her experience immigrating to Toronto from the West (Western) Banks of war-torn Palestine and Somaia-Carten shares her experience immigrating to Vancouver from Kenya, in hopes of living a better life. Both stories employ symbolism to accentuate the struggles of migrating to a new country.