Introduction
In the week one lab, members of the class were to classify six unknown rocks into one of the three rock types: igneous, sedimentary, and metamorphic. We were then to use that knowledge, along with other features of the rocks, to determine the rock name. This paper will identify each of the six samples based off the observations of each sample in the lab. The paper will go on to discuss the main properties of igneous, sedimentary and metamorphic rock. This paper will conclude with a discussion on what classification of a rock is the most useful in determining the name of the rock.
Rock A - Marble Rock sample A is marble. “Marble is a metamorphic rock that forms when limestone is subjected to the heat and pressure of metamorphism” (King, 2013). This particular sample is white in color and contains medium, coarse grains. The grains are visible and are easy to feel when picking up the rock and moving it between around in my hands. Marble has many uses in architecture and sculpture making it a popular material for these applications.
Rock B - Gneiss Rock sample B is gneiss. This sample was easy to identify based on the obvious banding throughout the layers of the sample. Gneiss is another metamorphic rock that originally was an igneous rock, granite. Through the process of metamorphism, the heat and pressures associated with the process may have caused the layers of mineral grains to flatten. “Gneiss displays distinct alternating layers composed of different minerals. Gneiss does not break along planes of foliation because less than 50% of the minerals formed during the metamorphism are aligned in thin layers” (UA, 2005). A visual inspection of the rock shows the quartz and feldspar composition within the layers of the sample.
Rock C - Limestone Rock sample C is limestone. Limestone is “organic sedimentary rock that forms from the accumulation
...ts were labelled with the upper case letters which represented the material types and a numeric letter. The artifacts were placed in different boxes. The artifact analysis was then conducted and the characteristics such as tool type and material type of each artifact were recorded on the artifact catalog forms. The material samples of lithic tools, faunal remains, and ceramics remains were compare with existing artifacts to identify their material type. The Vernier scale was used for the measurements of each lithic tools.
...e morphed it into the quartzite that is seen surrounding the butte (4). Rocks that undergo this process are called metamorphic rock, which is the same as the rock seen years ago by dinosaurs and other extinct creatures. The quartzite rocks were formerly seafloor sediment that was forced upwards, and then surrounded by lava basalt flows. Once erupted through fissures and floods through out most of the area, lava flow eventually created enough basalt to form a thickness of about 1.8 kilometers (1). All of this basalt flow eventually led to the covering of most mountains, leaving the buttes uncovered. The igneous lava flows and loess is reasons that the Palouse consists of such sprawling hills, and rich soil for farming (2). In result of the lava flows, the Precambrian rock Quartzite was formed. And lastly covered by the glacial loess, which were carried by the wind.
Shown in the picture above is volcanic extrusive igneous rock known as andesite. They were imported here to Laguna Beach to help minimize erosion (Merton Hill, p. 10-11). Extrusive Igneous rocks are formed on Earths surface due to lava quickly cooling or mixing with different materials such as ash or cinders from an eruption. There are two different types of extrusive igneous rocks; Plutonic and Volcanic. Andesite is known for being gray in color and being made up of very coarse grainy textures, which make it much harder to break down than sedimentary rocks. Unlike loose gravel and other sediments igneous rocks are known for being able to slow down seismic waves from earthquakes which cause less damage to surface structures.
Plummer, C.C., McGeary, D., and Carlson, D.H., 2003, Physical geology (10th Ed.): McGraw-Hill, Boston, 580 p.
Froede, Carl R. “Stone Mountain Georgia: A Creation Geologist's Perspective.” CRS Quartely 31, no. 4 (March 1995): 6.
A gallstone is a stone about the size of a pea, or marble which is made
and Metamorphic rocks can be found. There are also a lot of crusted plates, and violent
"Sedimentary Rocks." Backyard Nature with Jim Conrad. N.p., 18 May 2015. Web. 25 Oct. 2015.
Soon after the sea reached longer distance westward and the sandy tidal deposits were converted to deep water deposits. Mancos Shale is the name given to represent these deposits, which are comprised of organic material and small particulates. Another interesting fact to note is that this type of sediment consists of fossils. These remains can include prehistoric shell fish, shark teeth, and many other types of organisms. The hills seen at the foundation of the mesa in the Montezuma Valley are comprised of gray
Basalt is a commonly occurring igneous rock. More specifically however, Basalt falls under the category of Mafic Rocks. Mafic rocks have a poor Silica content, approximately 50% (Charles, Diane, Lisa, 2010) and contain high concentrations of metal oxides. Basalt is a fine grained rock containing predominantly ferromagnesian minerals, followed by plagioclase feldspar. The colour of Basalt ranges from dark grey to black and is relatively featureless. See Fig 1.
...y comes from the Balcones Escarpment. Larger crushed rock from this area is used as a base layer for roads and buildings, to protect them from the shifting soils. Very pure limestone is procesed into lime, wich is then used in a wide variety of agricultural, industrial, and construction activities. Other rocks crushed for building materials include basalt, used for railroad track beds, and marble, used for fancy terrazzo floors.
The geologic history of the Rocky Mountains has come about as an aggregation of millions of years. Briefly speaking, the formation of the Rockies transpired from hundreds and millions of years of uplift by tectonic plates and millions of years of erosion and ice have helped sculpt the mountains to be what we see today. The majority of the rocks that make up the Rocky Mountains began as simple shale, siltstone, and sandstone accompanied by smaller amounts of volcanic rock which formally built up for approximately 1.8 to 2 billion years in the ancient sea. By 1.7 to 1.6 billion years, these sedimentary rocks got caught in the zone of collision between parts of the earth’s crust and its tectonic plates. The incredible heat at the core of the mountain range then recrystallized the rock into metamorphic rock by the heat and pressure of the collision forces. Eventually, the shale would be transformed into both schist and gneiss. It is believed that granite found in the Rocky Mountain parks came from pre-existing metamorphic rock created shortly after the formation of the earth. Ultimately, the high mountains of the period were slowly eroded away to a flat surface exposing metamorphic rocks and granite. This process occurred around the period of 1,300 to 500 million years ago. This flat surface would become covered with shallow seas and rocks from the Paleozoic period and would be deposited and eventually cover the surface. There is...
The Rock Cycle The Rock Cycle is a group of changes. Igneous rock can change into
When reading or listening to poetry, the main objective for me is to feel moved. Happiness, longing, sadness are some of the feelings that can be achieved just by listening to others’ words. It is within these words that creates another world, or separates us from our own. Words all have a certain kind of attachment to them, so if used properly an author can stimulate a reader beyond belief.
There are two types of Igneous rocks. The first is intrusive, which is when the magma slowly cools beneath the earths surface. Because the magma is cooling slowly it allows the rocks end result to form crystal- like pigments. Examples of intrusive igneous rocks are Diorite, Gabbro, Granite, Pegmatite, and Periodotite. All of these rocks are course and grainy. The other type is an extrusive Igneous rock. This lava erupts onto the surface of the earth and cools rapidly also forming crystals, the lava cools so fast that at times it allows the rocks to form as clear-like glass. Examples of these rocks are Andesite, Basalt, Obsidian, Pumice, Rhyolite, Scoria,