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Tracking Earthquakes and Volcanoes Using Google Earth

Part 1: Tracking Earthquakes

An earthquake is a term used in science to describe the vibrations of the earth due to volcanic or tectonic movement. Many earthquakes originate from these tectonic regions. Listed below are earthquakes that occurred along the divergent, transform, oceanic-oceanic, oceanic-continent, and continental-continental boundaries.

1. This earthquake was a 6.2 in magnitude, having a focus depth of 9.9 km (6.2 miles), occurred in the Drake Passage region south of Argentina, South America, on April 14, 2012 at 6:56 AM local time. (April 14, 2012 3:56 AM MST) The Drake Passage Earthquake is an Oceanic-Continental convergence due to the relative location to the South America and Antarctica continents which creates a subduction zone where the denser layer is pulled into the layer below. This also is where “slab pull” occurs, which causes shallow focus earthquakes, such as the one noted here.

2. An earthquake with a 4.5 magnitude, with a focus depth of 154.8 km (96.2 miles), located in the Banda Sea, occurred April 13, 2012 at 1:02 AM local time (April 12, 9:02 PM MST). The earthquake that transpired in the Banda Sea occurred along a convergent boundary, in this case, an Oceanic-oceanic boundary. This type of boundary is usually located between two oceanic plates, and uses subduction in its process, but, unlike the oceanic-continental boundary, deep focus earthquakes often occur, such as the one noted below. Volcanic activity is initiated in these zones, and with time volcanic islands are formed, such as those that are located in the Banda Sea.

3. An earthquake with a 4.7 magnitude, with a focus depth of 10.4 km (6.5 miles) occurred at the Northern Mid-Atlantic Ridge on April 10, 2012 at 12:37 AM local time (April 09, 2012 at 08:37 PM MST). The northern Mid-Atlantic earthquake occurred along a Divergent Boundary, where molten flows upward through the opening between the plates, and where volcanic vents spill out basaltic lava flow; these are often called mid-oceanic ridges, and in this case is located along what is called the mid Atlantic ridge. These divergent boundaries often cause shallow earthquake focuses, and this one recorded below is no different.

4. A 5.9 magnitude earthquake with a focus depth of 10.2 km (6.3 miles) occurred off the Coast of Oregon on April 11, 2012 at 1:41 PM local time (3:41 PM MST). This earthquake occurred on a transform fault, where two plates slip past each other in a vertical manner. These types of faults cause shallow focus earthquakes, such as the one noted here. This particular transform fault is located just outside an oceanic-continental subduction zone but is itself a divergent boundary as its movements are more consistent with a transform fault than a subduction zone.

5. A 4.2 magnitude earthquake with a focus depth of 10.6 km (6.6 miles) occurred on April 11, 2012 at 9:29 PM local time (also MST). This earthquake occurred in an area where no oceanic plates are located, but rather occurred where two continental plates are located, and is therefore on a continental to continental boundary. Continental-continental boundaries occur because there is no oceanic plate and are too buoyant for subduction to occur; without subduction occurring, these plates collide together. These types of plate movements create mountain ranges, such as those scattered throughout Utah, including this area where the earthquake occurred.

Part 2: Tracking Volcanoes

A volcano is a vent within the Earth's crust that vents or has vented hot rock, molten lava or steam. After the sediment from many eruptions has been deposited, a shell forms over the vent, creating a mound or mountain. Some of these volcanoes will become inactive with little to no activity while others will have no activity and become extinct. Inactive volcanoes can remain dormant for many years and then, will erupt spewing forth lava and debris in what is usually a violent manner. After this eruption the shape of the terrain will change and the volcano will take on different characteristics. There are still many volcanoes are active and continue to work below the surface.

1. Shiribetsu, Hokkaido, Japan. This is an example of a Composite or Strato-Volcano. Shiribetsu is near an oceanic-continental tectonic boundary. Through the subduction process, the Kuril trenches formed and, as a result the chain of volcanoes located in Hokkaido (including Shiribetsu) formed.

2. Haleakala Volcanic Range in Maui, Hawaiian Islands USA. This is an example of a shield volcano. Haleakala is located on a divergent boundary. This volcano is located within the Pacific rift, part of what is called the "ring of fire". It was created from "Hot Spots" through which high pressure and hot magma erupted and over time created the island chain.

3. Bald Knoll, Utah, USA. This volcano is of the cinder cone type. This volcano sits within a continental-continental tectonic boundary, which also helped form the mountains of the region. Notably, Bald Knoll is the youngest basaltic cinder cone volcano in the region.

4. Tofua, Tonga Islands in the Southwest Pacific. This is an example of the caldera volcano. This volcano is lies near an oceanic-oceanic converenge boundary. This volcano was likely a strato-volcano, but at some point in its history a massive eruption caused the magma chamber to empty and resulted in the collapse of the structure.

Part 3: Reflection

I. Earthquakes, volcanoes and even the Tectonic forces that drive them are all intertwined, moving and forming and venting in what seems to be a never-ending cycle. They move, create change and even destroy much of what is now the surface of the planet Earth. Earthquakes are the effect of Tectonic Plate movement, and Volcanoes are the tools and even aftermath of these movements. Without these forces creating and expanding continents and islands, we would not have the unique landscape and character that is the planet Earth. Life as we know it could not exist without these forces at work.

II. Earthquakes and Volcanoes have one thing in common: the tectonic plates that move and shift beneath them. It is this driving force that causes both earthquakes and volcanoes to occur. Tectonic plates are vital for the creation and growth of a planet, and earthquakes are a necessary part of this, as are the creation of volcanoes. Earthquakes are necessary for tectonic plate movement, for without the plate movement, the planet would remain stationary and possibly lifeless. Earthquakes are the figurative starting gun in the marathon of planet building. One cannot have plate movement without the shakes, rattles and rolls that come with earthquakes. As the tectonic plates move, slip, subduct and collide into, beside and beneath each other, immense pressure builds; pressure that must be released. Volcanoes provide this release, venting out excess lava flow and allowing for more movement within the earth. One does not know for certain what would happen if volcanoes were not here to provide the vents for the tectonic plate movement, but one can imagine it would be rather like a balloon exploding after being crushed under weight.

III. What I learned from the study of earthquakes and volcanoes was their relationship with each other, also that these forces are what provide the resources that man has and will in the future use for his development. What is amazing is these forces are at work everyday, moving and shaping our planet; a planet that seems to be much younger than the others in the solar system. Without these forces, this planet would not perhaps be the perfect place for life to exist.

IV. Earthquakes and Volcanoes are dangerous wonders that are necessary to maintain the earth and man. Without these forces there would be no land for man to settle and thrive upon, nor would man have the resources available to help with this. With the progression of man, so will the use of these resources change and grow. It is good that man has an awareness to the dangers of these forces, and, as technology improves, so will man's ability to prevent a repeat of past disasters. With this information, my worldview has changed only in a heightened awareness to them, and a greater interest in these forces affecting the place in which I live; past, present and future.