Similarities And Differences Of The Three Rondavels

The aim is to identify and associate landforms, rock types and soils to the natural environment and its plants and animals and also to investigate the history of the local environment, comprising human impacts over the last 50 years. The impact of human alterations to the environment includes increased soil erosion and changes in river flows.

At Laurel Hill Duke Forest there is a large granodiorite cliff adjacent to a river on one side. This cliff is not smooth and has several parallel fractures instead of one steep slope. Observations of this cliff were taken in order to gather data and find possible explanations for why this cliff is where it is located and why the river adjacent to it follows a V-shaped path. One observation was that the range of the strikes and dips of the fractures facing river were all near parallel ranging from strike of 170-190 degrees and dips ranging from 70-90 degrees. There were other fractures oriented differently on other sides of the outcrop. Also, the surface of the outcrop was highly weathered in some parts where the rock type was not distinguishable without using a rock hammer and had moss growing over it.

Next, we can see that the rock displays a subtle porphyritic texture with plagioclase comprising the phenocrysts. The overall texture of the surrounding groundmass is granoblastic equigranular. Under thin section we also see a weakly defined foliation evidenced in the preferential alignment of actinolite grains and to a lesser extent chlorite grains. Undulose extinction is also observed in quartz indicating the rock was subject to deformation. The normalized quartz, alkali-feldspar, and plagioclase (QAP) values of this rock indicate that it is classified as a grano-diorite according to the IUGS QAPF classification system which is consistent with the hand sample interpretation.

This formation is a very fine grain Mississippian limestone. To test to see if this was the Bangor formation we used HCL and because there was a reaction we know its limestone. This formation could also be described as gray in color as well as an average thickness of 700 feet. We see the Bangor until stop eight, where we see a very different vertical bedding. Also different at stop eight is the outcrop no longer reacts with HCL. From this we gathered that we had moved into the Hartselle formation. In the Hartselle Formation, Mississippian aged sandstones are dominant. This particular stop had a large amount of jointing. After the Hartselle, we figured the Pride Mountain Formation would be next, however at stop nine we see the Maury Formation present. This stop focused on the rock located inside the creek. Because we were unable to go into the creek to get the strike and dips, we once again had to do a projected orientation. Also found on this stop were natural sulfur springs, easy to notice with the smell that it gives off. The Maury formation consist of Mississippian- Silurian aged shale. At the next stop, stop 10, we encounter the Ft. Payne formation. Although this area location was thickly vegetated, we were able to conduct the acid test and saw that the HCL reacts in some places but not all. From this we concluded that this was the cherty limestone of the Ft. Payne formation. The following stop, 12, we went up section and arrived at the Maury Formation once again. At the final stop, location 13, we see Ft. Payne Formation. All of the metamorphism and deformation in the southernmost Appalachians can be related to the movement of the thrust sheets and stacks (Higgins,

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,

This study classifies the two granites under one unit named the Kilbride Granite, however, the research, which uses both radiometric dating and composition analysis, identifies them as two compositionally separate units with different ages. On the other hand, it is not wrong to say that the granites were related as they are the two latest forming members of the Eastern Red Hills complex. (Bell and Harris, 1986)

The third and topmost layer of geological deposits is the Pleistocene sediment, from the Quaternary Period, which can date up to 1.7 million years old (L). This layer contains sediments of Holocene from ten thousand years ago as well as Pleistocene from 1.7MY to 10KY(L). Continent wide ice sheets deposited the glacial sediments during numerous ice ages (DVLR) and can be seen at Don Valley Brickyard. The York Till is above the bedrock, and was left 135,00 years ago by an Illinoian ice sheet. Above the till is the 80,000-year-old Don Formation that was caused by the Sangamon Interglacial, and indicates climate change by the alternation of sand and mud. Above the Don Formation, all other deposits are from the Wisconsin Glaciation. The Scarborough Formation consists of clay and then sands, and was formed 60,000 years ago. Above this is the Sunnybrook Drift and the Thorncliffe Formation from 45,000 years ago consisting of seminary

At the nearby valley wall, there is a distribution of rock lithology including mostly Limestone. The roundness of the samples is all angular, with a mean size of 8.325 cm in diameter. However, the stream bank has more clastic rock samples which have a rounder shape and a smaller mean size of 7.975 cm. These contrasting sections are between alluvium and colluvium data where the alluvium

The latest rocks in this region were formed in Pleistocene time as imperfectly consolidated gravel of river terraces and alluvial deposits of the

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 Ouachita Mountains were also created with the collision of Gondwana as it pushed together seafloor and are tilted or twisted folds of earth crust. Streams usually flow along the folds. Most of the mountains are made up of sandstone and shale from the bottom of the former sea. This region is usually known for unique quartz crystals,

Mesa Verde National Park on the Colorado Plateau contains many geological aspects of interest, including its sedimentary rock layers, its canyons, its alcoves utilized by ancient people and how these alcoves were formed. Mesa Verde National Park is located in the southwest corner of Colorado, close to the Four Corners area, on top of a high mesa overlooking the Mancos River (Harris et al. 2004). The park, covering 81 square miles, consists of several main sedimentary formations that are characteristic to the park (Encyclopedia Britannica 2015). Canyons are carved into the sedimentary rock, with the cave dwellings found high on their steep walls. These dwellings are an especially unique aspect to the Mesa Verde National Park, and are built out of large alcoves. The alcoves were produced by weathering and erosion of the sedimentary rock type. To better understand how these alcoves formed, we must understand the geology of Mesa Verde National Park and how it has developed over history.

The Plains take second place! This region was created when soils by rivers and lakes from the Canadian Shield were deposited at this regions edge. In addition, sedimentary rock was formed from these deposits, which became huge areas of flat, fertile lands, river valleys, and rolling hills. To add, there are three flat levels and each consists of hills, cliffs, low mountains, forests, wide river valleys, and sand

Majority of the Canadian Shield is made up of metamorphic and igneous rocks. The rocks

One piece of this history is the subsurface Paleozoic rocks. Paleozoic rocks are for the most part hidden in the Park despite being in the Colorado Plateau, which is likely due to both erosion, and it being buried in other various rocks. Next is the deposition of the Moenkopi Formation during the early Triassic time period. When North America was still apart of Pangea, the area that was the Colorado Plateau was located within close range of the Equator. 300-600 feet of sand and mud were accumulated during this time, with marine life being included which tells Geologists that the sea sometimes was in the area. The climate at the time was warm, with varying times of humid and dry spells. There is very few beds of the Moenkopi Formation left in the area once again due to erosion. Third is the deposition of the Shinarump Member of the Chinle Formation. This basal conglomerate was deposited on top of the Moenkopi Formation. It is made up of gravel and sand, which indicates that there was water depositing it. The Shinarump Member also averages between 35-50 feet thick. Next in the geological history is the deposition of Chinle beds later in the Triassic time period. When the sea regressed to the west of the area, a large plain was left behind. As the climate changed, so did the environment. Soon grasslands and marshes began to form in the area. During this time hundreds of feet of shaly material accumulated which formed both the Lower Petrified Forest Member and the Upper Petrified Forest Member. In some parts, these two members are separated by the Sonsela Sandstone Member, composed of the most petrified wood compared to all other rock units featured in the Park. The Owl Rock Member is at the top of the Chinle Formation, and completes it. Near the end of the Triassic time period, tectonic activity was occurring heavily in the Arizona basin. In the western sea at this time a chain of volcanoes erupted,