Types of Rocks

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.

The youngest of these rocks are dated at about 220,000 years ago. Rhyodacties and quartz latites in the modern caldera area extruded from about 320,000 years ago to 260,000 years ago, and then silica-rich rhyolites at Glass Mountain northeast of the caldera erupted from about 210,000 years ago to 80,000 years ago. The scattered distribution of the initial mafic eruptions indicates that they were erupted from the mantle, while the slightly younger domes and flows were from a deep-crustal source. The youngest rhyolite eruptions erupted at the northeast rim of the caldera at Glass Mountain and were the first activity of the silicic Long Valley magma chamber (Bailey, et. al., 1989).

Despite a family history of geophysicists and rock enthusiasts, I’ve never found the subject of rocks particularly fascinating. However, an exploration of Earth Science has lead me to the discovery that rocks are actually hidden gems (often literally), and that there’s more to the topic than one would think.

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.

Silicious lava, forced up from deep down below. Soda trachytes extruded in a highly viscous state, building the steep-sides mametons we see in Hanging Rock. And quite young, geologically speaking. Barely a millions years old. (Greene, 11)

Convection currents may bring magma to the surface at diverging boundaries. Sedimentary rocks from the ocean floor gets pushed down to the mantle at convergent boundaries. The crust soon melts and rises to the surface creating igneous rock. Typically mountain ranges are metamorphic rock, maybe our mountains are.

A period of volcanism resulted in igneous intrusions within the Raton Basin-Sierra Grande Uplift Province that was sourced from the upper mantle about 26. 6 billion years ago and is associated with parallel dikes and sills (Higley, 2007). Igneous rocks are common within the Raton Basin and include Tertiary dikes and sills that range in age from 6.7 to 29 5 million years ago (Flores and Bader, 1999). One of the main differences between dikes and sills is that dikes are longer lived magma conduits and sills are features that form when magma is in neutral buoyancy with the surrounding rock (Rooper et al., 2006). These volcanic events are associated with hydrothermal alteration of coal within the basin (Higley, 2007).

Some rock’s in the Earth’s interior that are solid, are so hot that, if the pressure on these were released, or they are convected into a lower pressure zone, they could begin to melt

The only types of rocks found in Big Bend National park are Sedimentary (N.P). The specific names for these rocks are: limestones, shale and sandstones, clay, Lava Flow, Conglomerate, Marl, and Cherty Limestone are found in this park (N.P). These rocks were likely abundant throughout the park; when the area was covered by a salty sea during the Cretaceous period (N.P). The way how these rocks formed is by the results of pebbles being cemented together. Another way how the rocks can form is by how the earliest layer of rock was deposited in a relatively deep marine environment. After the next layer above the shale indicates that the rock is deposited in a very shallow way, that's when the ocean water starts

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).

Geologist recognize three distinct sets or groups of rocks found in the Grand Canyon. These are the Vishnu Basement Rocks, the Grand Canyon Supergroup and lastly, found in the top two-thirds of the canyon the

the Earth at tremendous velocities causing them to join the molten and create a crust

     Igneous rocks are classified first by texture. This is broken down mainly into grain size. First there are intrusive, or plutonic igneous rocks. These types of rocks cool within the crust and forms large, visible crystals. The opposite would be extrusive, or volcanic rocks. These cool at the surface rapidly, forming small grains. A combination