Metamorphic Rock
Metamorphism means to change form; this is exactly what metamorphic rocks do. This paper will take a look at the Earth’s rock cycle to examine exactly where the metamorphic rock fits into it. It will also look at how metamorphic rocks are formed and the relationship between metamorphic rocks and igneous rock and sedimentary rocks. This paper will examine the geological characteristics and materials of metamorphic rocks, and examine some examples of metamorphic rocks and will describe mineral composition of some examples and explain its economic uses.
The Rock Cycle The rock cycle helps people to understand the starting point of the igneous, sedimentary, and metamorphic rocks. In addition to explaining how each of the
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Regional metamorphism usually occurs during the formation of a mountain. Large amounts of rock are subject to extreme pressure and heat while the Earth’s crust is moving to create a mountain. Regional metamorphism also takes place when there is a collision of two continental plates. The force from the collision puts forth enough extreme pressure needed for a rock to go through a metamorphic change.
Relationship Among the Three Rock Groups
When sedimentary rock and igneous rock are exposed to extreme heat or pressure, they can change their appearance and mineral make up. The color and density of the rock can change as the mineral and density changes the structure of the rock. The rock under pressure and heat doesn't melt but the chemical or mineral structure of the rock condenses and compacts changing the rock to metamorphic rock. This chemical reaction will cause the rock to change color with the mineral grains and will give the appearance of strips. The metamorphic rock can keep changing its density and appearance when it is exposed to more heat and pressure. The rock type of granite gneiss and biotite schist that are found in the Green Mountains of Vermont are two types of metamorphic rock.
Examples of Metamorphic Rocks
There are many different types of metamorphic rocks that one can see on a regular basis; many probably do not realize they are metamorphic rocks. For example, slate
The collection of the rocks was based on just picking up the most amount of difference looking rocks that was possible and bringing them home to analyze. This was done for about two months from many difference locations including campgrounds, beaches, rivers, highways as well as construction sites. After about two months there were many rocks so I started to analyze and take out the rocks that were of the same kind. I found many granite, basalt and conglomerate rocks.
Next, these rocks undergo erosion, which is the process of moving sediments from one place to another. Then, these sediments are deposited all at one place and over time they start to converge and cement as layers which are also known as strata. As time keeps going, new sediments deposit and cement together over old ones forming new layers. This is a repetitive process that eventually build up layers to make up a Sedimentary rock. Approximately 40 major sedimentary rock layers exposed in the Grand Canyon National Park area range in age from about 200 million to nearly 2 billion years old. As you can see, sedimentary rock formation takes an excessive amount of time.
Emilie Tixeront explains the rock cycle, the formation of the Glasshouse Mountains, and what makes rocks so special anyway.
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.
Rocks: Students learn about rocks through the use of a film. The student uses a white board to take notes, and organizes notes with the use of a graphic organizer.
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
4. Choose one of the geological periods listed in figure 3.8 and find out all you can about it. How are rock formations from that period identified? What are its most characteristic fossils? Where are the best samples of rock from your chosen period?
I believe that the rock cycle has an impact on Colorado because of the sedimentary, igneous and metamorphic rock cycles that lead up to the formation of the Earth’s mountains, and terrains. These different steps lead up to the rock cycle. To turn igneous to sedimentary, they are easily eroded, it breaks down to sediment. Sedimentary to metamorphic, sedimentary rocks are subject to pressure so it produces a chemical reaction. Metamorphic to igneous, when metamorphic rock gets hot, it melts turning it into igneous rock and this precedes the rock cycle.
All of the volcanic and metasedimentary rocks are metamorphosed, whose grades are extending from greenschist to upper amphibolite, characterized by low-pressure but high-temperature (Isachsen & Bowring, 1994). The influence of basement fracture zone is reflected in the homoclinal and abruptly alternated trends of the volcanic belts, which is more frequently found in the southwestern domain of the province, while north belts show angular patterns (Fyson & Helmstaedt, 1988; Padgham,1992; Padgham & Fyson, 1992). Except for the sharp dips of the volcanics, regional-scale folds, foliations and cleavages over several successions shown in the metasedimentary rocks are studied to understand the deformation and metamorphism (Isachsen & Bowring, 1994). Fyson & Helmstaedt (1988) compare three major types of folds which are ranked by their ages and sizes from oldest, most extensive F0 to minor-sized, cleavage-foliation-associated S3 folds with intermediate type F1 between them and they suggest that the parallel trend and they suggest both foliation and folds are results of syntectonic
It is currently the largest exposed granite in the world weighing approximately one trillion pounds; although, only one third of the mountain can be seen as a majority of the mountain expands below ground as far as North Carolina. The enormous pluton mountain, as scientifically identified by geologist, was formed by a complex folding and faulting that had subsequently created the Blue ridge mountains. Though what remains as a mystery to many geologist is as to how such a massive granite mountain has become exposed. Although there are several theories that have been publicated to explain such a phenomena none are substantial or advocated the most. While the origins of Stone Mountain are elusive, the correlations of this landmarks with american history are intricately
and relationships of a working model. If a testable hypothesis is confirmed by a large
The Blue Ridge Mountains sit within a larger tectonic area that includes part of the smoky mountains and Appalachian mountain chain. The Blue Ridge Mountains sit upon a large thrust plate area that has experienced repeated movement in the orogeny process as the Appalachians were built. This process occurred during the Proterozoic to the Paleozoic period (Tectonic Setting of the Southern Appalachians). Evidence of the faulting includes sedimentary zones at the end of the thrust. Within the thrust areas is high-grade metamorphic rocks and some igneous rocks from intrusion during collision events (Hatcher, R). Evidence of the intrusions are the dikes which can be seen and the large granite facies throughout the area (Grant, Willard).
The New Madrid Seismic Zone is also known as the New Madrid Fault Line. A fault is a thin zone of crushed rock that separates the Earth’s crust. Whenever an earthquake takes place, it occurs on one of the faults. Then the rock on one of the sides slips with respect to the other. The fault line is made up of reactivated faults. The reactivated faults formed when North America began to separate. Faults were formed next to rift and igneous rocks were formed from the magma that was pushed up to the surface (Wapedia (2010). The rift was covered with younger sediments. The sediments that covered the rift included Mesozoic and Cenozoic sedimentary rocks of the Mississippi embayment. Large amounts of the sediment was loosely consolidated, soft and sandy as a result of the ground shaking, ground deformation, slides, slumps, and liquefaction. A mass of intrusive igneous rock (also known as pluton, mass of igneous rock and a deep reservoir of magma)
Rocks are classified to make it easier on people to identify them in the future. This can be done by a numerous amount of ways. Each rock type has their own specific ways, but there are two distinct characteristics that apply to all. These are texture and composition. These two, along with many others helps to classify igneous, sedimentary, and metamorphic rocks.