a. strain buildup only b. location of foci c. magnitude of P-waves [pic] d. reoccurrence rates of earthquakes in an area and the rate of strain buildup 2. What are most earthquakes associated with? a. rift valleys b. mid-ocean ridges c. divergent plate boundaries [pic] d. plate boundaries 3. At what point in the graph would a rock be permanently deformed? [pic] a. at the start of the stress [pic] b. past
What is "summit deflation"? (page 94, para 2 to page 95) Summit deflation, which is measured by tilt meters in parts per million, is when the slope of a volcano changes usually relatively prior to an eruption. 4. How does Kilauea's magma move upward
There is a convergent boundary on the west side of the United States. At a convergent boundary, two plates collide, and the denser plate is subducted. Volcanoes and earthquakes are common as a result of pressure and friction. There is also a transform boundary forming the San Andreas Fault which is between an oceanic plate subducting under a continental plate. 3.
Geologic Summary. The high, isolated massif of Shiveluch volcano (also spelled Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group and forms one of Kamchatka's largest and most active volcanoes. The currently active Molodoy Shiveluch lava-dome complex was constructed during the Holocene within a large breached caldera formed by collapse of the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large eruptions of Shiveluch have occurred during the Holocene, making it the most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent collapses of lava-dome complexes, most recently in 1964, have produced large debris avalanches whose deposits cover much of the floor of the breached caldera.
For example, the origin of puzzling, hilly volcanic deposits near Mount Shasta and Mount Rainier became clear. Gravitational collapse of volcanic flanks is now seen as a normal event at steep-sided volcanoes, even on the ocean floor and on other
I will be discussing factors that cause differences in hazards posed by volcanoes. I believe the most important factor is the location of a volcano and the type of volcano. The most explosive and therefore dangerous volcanoes are found on destructive plate boundaries (Over 80% of the worlds volcanoes occur at these boundaries) for example the eruption of the Nevado del Ruiz in Colombia on the 13th November in 1985 which killed over 25000 residents of Arenas and Armero. At destructive plate margins, the oceanic crust is denser than continental crust and is therefore subducts under the continental crust. Due to high temperatures in the mantle of around 3000 degrees centigrade, this oceanic crusts melts and then rises due to the convection currents in the aesthenosphere .
Before 1980, the last eruption of Mount St. Helens was between 1840 and 1850. The volcano did not happen overnight however, it was caused by multiple earthquakes and lots of pressure buildup through time. The Mount St. Helens volcano eruption was the most recent volcanic eruption that did significant damage in the United States. The formation of Mount St. Helens millions of years ago is the reason why the eruption was so violent. The Juan de Fuca Ridge, which lies between the Pacific and Juan de Fuca plate pushes the two plates in opposite directions causing the Juan de Fuca plate to sub duct underneath the continental plate causing a subduction zone and large pieces of rock are pushed into the opposite plate causing a mountain to form.
A magnitude 4.2 earthquake on March 20, 1980 preceded by several smaller earthquakes beginning as early as March 16, was the first substantial indication of Mt. Saint Helens awakening from its 123-year slumber. With a thunderous explosion, widely heard throughout the region around noon on March 27, Mt. Saint Helens began to spew ash and steam, marking the first significant eruption in the conterminous United States since that of Lassen Peak in California. The crown of the ash column rose approximately 6,000 feet above the volcano.
This type of volcano can be recognized by its broad, gentle slopping shape. The lava dome that composes a shield volcano is usually built over a period of time. When this type of volcano erupts it often involves a flow after flow of lava. An example of shield volcano is Mauna Kea, which along with Mauna Loa forms the large island of Hawaii. The largest shield volcano in the solar system is Olympus Mons, on the planet mars.
Earthquakes Sheila Fangmeier GEO101 – Earth Science Colorado State University – Global Campus Karen Stelly October 5, 2014 Earthquakes “An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves” (Earthquake, 2014). Seisometers measure earthquake magnitude and intensity based on two scales, the Richter and Mercalli. An earthquake’s magnitude can range from less than 2.0 to greater than 9.0 on the Richter scale and its intensity I to greater than VIII on Mercalli (Richter magnitude scale, 2014). The depth focus is important to how much damage can occur on the Earth’s surface. An earthquake’s depth can be considered shallow (less than 70km), intermediate (between 70km and 300km), or deep (300km to 700km) (Earthquake, 2014).