Joffree Herrera
Geography 1000
E Portfolio
Part 1:
1.
On October 22, 2010 there was an earthquake in the Federated States of the Micronesia region.
This earthquake occurred at 14:46 Coordinated Universal Time, with the depth of 9.38 miles and the
magnitude of 5.1. The boundary type for this earthquake is oceanic- oceanic convergence. In an
oceanic- oceanic convergence two oceanic plates collide and subduction will occur, which is when one of
the plates over laps the other. As you can see in this image the earthquake location is surrounded by
only ocean.
2.
On October 23, 2010 an earthquake occurred in kepulauan Alor, Indonesia. This earthquake was
recorded at 5:38 Coordinated Universal Time, with the Magnitude of 4.4 and the depth of 64 miles. I
believe this earthquake is located on an oceanic- continental convergence type of tectonic plate
boundary because it is not only in the ocean but also very close to land. When the oceanic and
continental plates collide the oceanic plate will sink beneath the continental plate and the earthquake
will occur at the trench.
3.
On October 21, 2010 an earthquake occurred in Tajikistan. This earthquake took place at 10:58
Coordinated Universal Time with the magnitude of 4.4 and the depth of 96.93 miles. I believe this
earthquake is located on a continental – continental convergence type of tectonic plate boundary
because when two continental plates collide the result is a large mountain range. As shown in the image
this earthquake is located in the Pamirs Mountains.
4.
On October 23, 2012 an earthquake occurred in the Southeast of the Loyalty Islands. This
earthquake was recorded at 9:39 Coordinated Universal Time with the magnitude of 6.0 and the depth
of 78.91 Miles. I believe this earthquake is located on a divergent type of tectonic plate boundary
because it is located on a mid-ocean ridge. Mid- ocean ridges are made when magma wells up from the
asthenosphere pasted the lithosphere between plates.
5.
On October 28, 2012 an earthquake occurred in the Queen Charlotte Islands, of the Canada
region. This earthquake was recorded with the magnitude of 5.5 at 3:14 Coordinated Universal Time,
with the depth of 6.21 miles. I believe this earthquake is located on a transform type of tectonic plate
boundary because transform faults are found on the mid-ocean ridges and can extend through the
continent. In this image you can actually see two earthquakes very close to each other only minutes
apart. One is in the ocean the other is more in land.
Part 2:
1. The volcano Mount Fuji is an example of a composit volcano. This composit volcano occurs along an
oceanic – continental tectonic plate boundary.
2. The volcano Sierra Negra in the Galapagos Islands is one of six shield volcanoes. All six of these shield
volcanoes are driven by hot spots.
3. The volcano Nevado del Huila in Colombia is an example of a cinder cone volcano. This cinder cone
volcano is on a divergent type of tectonic plate boundary.
4. The volcano Pinatubo in the Philippines is an example of a caldera volcano. The Pinatubo is on an
oceanic- oceanic convergent tectonic plate boundary.
Part 3:
In the past few weeks there was a lot of new information gained regarding earthquakes and
volcanoes and their relationship with one another. We covered the earth’s structures, continental drift,
plate tectonics, plate boundaries, and then we went into great detail on both volcanoes and
earthquakes.
Continental drift is the hypothesis that the earth was pangia. Pangia meaning the earth was
originally one piece and then broken apart into smaller pieces. There is evidence that supports this
theory including mountain ranges in two different locations that match each other as if they were once
joined.
Plate tectonics is the theory of the lithospheric plates shifting and being rearranged. Seafloor
spreading is held responsible for the pulling apart of the lithospheric plates. Once these plates have
been moved magma from the earth’s surface will rise in the mid-ocean ridges. The mid-ocean ridges and
oceanic trenches show a pattern of where earthquakes occur.
There are three different types of plate boundaries.
1) Divergent Boundaries: Occurs when the plates move away from each other.
2) Transform Boundaries: Occurs when two plates slide past one another.
3) Convergent Boundaries: Occurs when two plates run into each other.
Convergent boundaries include:
Oceanic – continental convergence: The denser ocean plate subducts beneath the continental plate.
Earthquakes take place at the margin of the subducting plates. They are shallower at the trench but as
subduction continues the earthquake continues to get deeper. Volcanoes are made from magma that
has been generated in the subduction zone.
Oceanic – oceanic convergence: Takes place when two oceanic plates come in contact with one another
and subduction takes place. Earthquakes occur and volcanoes begin forming on the ocean floor.
Continental- Continental convergence: Takes place when two continental plates collide. This is the one
convergence where subduction does not take place. Instead mountains are formed. With this type of
convergence earthquakes occur.
There are several types of volcanoes including:
Shield Volcanoes- also known as “gentle giants” they are created by lava flows. Even though the
eruptions are mild they can still destroy vegetation and property.
Composite Volcanoes- These volcanoes are very explosive and erupts lava and pyroclastic material.
Composite volcanoes occur where there are oceanic – continental boundaries and oceanic – oceanic
boundaries.
Cinder Cone Volcanoes- Are the smallest volcano type.
Caldera Volcanoes – Are volcanoes that have collapsed in on themselves.
Earthquakes are abrupt movements of crust which are usually associated with a sudden slip
along faults. There are four different types of faults including normal (caused by tension in the crust) ,
reverse (caused by compression in the crust) , thrust fault (similar to the reverse) , and strike slip fault
(horizontal movement).
Earthquakes are measured by the Richter scale which measures the amount of energy released.
They are also measured by the Mercalli Intensity scale which is a system used to rank the intensity of
damage left behind.
In conclusion both earthquakes and volcanoes can relate to the theory of plate tectonics. The
theory of plate tectonics explains that plates move and collide with one another over time. As you take
note of where the earthquakes and volcanoes are taking place you will notice they are along the plate
boundaries.
Side note:
All images are screen shots taken from Google earth. Thank you Google.