Interdisciplinary - Human Geography
Description:
As a learning community, these two courses are integrated as fully as possible both in terms of content and pedagogy. You will look at Natural Disasters through the lens of Writing and Social Justice, and you will look at Writing and Social Justice through the lens of Natural Disasters. Both instructors will be engaging with you here in this single Canvas site and will help you make active connections between the courses. Remember that a learning community is TWO classes which work together, so the amount of time you give to this learning community should be equivalent to the amount of time you would give TWO full courses. You will receive two separate grades--one for GEOG 1700 and one for ENGL 2640. The classes will have a shared semester project (you do ONE project and get credit for it in both classes), but the rest of the assignments will be specific to each course in terms of grading, but linked as much as possible in terms of content.
English 2640 (HU) examines how writing can activate a reader’s moral imagination thereby functioning as an act of social justice. We will discuss theories and conceptual frameworks of social justice as well as multiple social justice issues such as racism, sexism, classism, and ableism. Using narrative theory, we will explore through reading and writing the ways in which multiple genres address social justice and human rights issues, particularly those related to natural disasters and the environment.
Geography 1700 (PS) teaches a scientific and spatial understanding of natural processes that shape the surface of our planet and the systems that exist between the atmosphere, climate, hydrosphere, lithosphere, and biosphere within the context of the human environment. Course also investigates the social dynamics that are influenced and impacted by natural disasters, particularly those related to poverty, gender inequality, and racism.
Chapter 1: Introduction to Natural DisastersNatural processes such as volcanic eruptions, earthquakes, floods, and hurricanes become hazards when they threaten human life and property. As population continues to grow, hazards, disasters, and catastrophes become more common. An understanding of natural processes as hazards requires some basic knowledge of earth science. By the end of this chapter, you should be able to:
- Understand the science of natural hazards
- Determine how natural hazards are connected
- Explain how natural hazards become disasters and catastrophe
Chapter 1 - U.N. Millennium Development Goals (MDGs) (Links to an external site.)
Here is what I learned from this assignment from Chapter, 1.
This is a really neat website. I love their development goals, they are all very important to the future of this world. For a moment there, I tried to imagine a world without these types of issues. It seemed too good to be true.
One thing I am really interested in is gender equality. So, naturally the Gender equality goal stood out to me. I definitely feel like schooling should be made completely equal, not only is it a human right, but it is important to the survival of human beings. In natural disaster situations, like a hurricane in a poverty stricken country. We need people to work together equally as a team, if women are not educated to the extent that men are, then they are harming themselves by having these gender restrictions because they are cutting their chances of survival by half. The reason I say half, is to assume there are equal amount of men and women in these situations. If women in these countries had the opportunity to be educated equally they would be able to help out financially with any damages to their homes and farms, etc as well as being educated enough maybe even help the injured in the community as well. Women have spent ages in the shadows on men and where has it really gotten anyone? It may make mens lives a little less stressful, because they don't have to cook their own meals, bare children, or oftentimes even raise them. However, if men and women would have always been equal, I believe that our world would be a lot better off and all of these Millennial Development Goals, would have been accomplished ages ago.
The second one I viewed was the one about Ending child mortality. As excited as I was about how much the child mortality rate has gone down, it was sad to know that the mortality rate still exists. Obviously, children will sometimes die in this world, just like everything else. However, if we can prevent it by simply having measles vaccines available, then we need to have these things available. It is a human right to have healthcare, worldwide. I thought it was interesting to learn that children whose mothers have even a basic education will live longer, or have a less mortality rate than that of an uneducated mother. In terms of natural disasters; I believe that the child mortality rate will definitely drop if we are able to educate mothers, and entire communities about how to better prepare for natural disasters in their area and how to better prepare their children. These people need to know about where they are living and any other country should come in and assist them with setting up environmentally safe zones and housing, schools etc for these people. I mean, honestly, I don't get why more Americans aren't being shipped out to other countries to help them out more often. The government needs to buy our plane tickets and mandate that we all help each other. Especially, the most wealthy countries in the world. I feel like if the wealthier countries got together and helped educate these poorer countries on how to protect themselves when a natural disaster strikes, that the child mortality rate would drop much more.
This is a really neat website. I love their development goals, they are all very important to the future of this world. For a moment there, I tried to imagine a world without these types of issues. It seemed too good to be true.
One thing I am really interested in is gender equality. So, naturally the Gender equality goal stood out to me. I definitely feel like schooling should be made completely equal, not only is it a human right, but it is important to the survival of human beings. In natural disaster situations, like a hurricane in a poverty stricken country. We need people to work together equally as a team, if women are not educated to the extent that men are, then they are harming themselves by having these gender restrictions because they are cutting their chances of survival by half. The reason I say half, is to assume there are equal amount of men and women in these situations. If women in these countries had the opportunity to be educated equally they would be able to help out financially with any damages to their homes and farms, etc as well as being educated enough maybe even help the injured in the community as well. Women have spent ages in the shadows on men and where has it really gotten anyone? It may make mens lives a little less stressful, because they don't have to cook their own meals, bare children, or oftentimes even raise them. However, if men and women would have always been equal, I believe that our world would be a lot better off and all of these Millennial Development Goals, would have been accomplished ages ago.
The second one I viewed was the one about Ending child mortality. As excited as I was about how much the child mortality rate has gone down, it was sad to know that the mortality rate still exists. Obviously, children will sometimes die in this world, just like everything else. However, if we can prevent it by simply having measles vaccines available, then we need to have these things available. It is a human right to have healthcare, worldwide. I thought it was interesting to learn that children whose mothers have even a basic education will live longer, or have a less mortality rate than that of an uneducated mother. In terms of natural disasters; I believe that the child mortality rate will definitely drop if we are able to educate mothers, and entire communities about how to better prepare for natural disasters in their area and how to better prepare their children. These people need to know about where they are living and any other country should come in and assist them with setting up environmentally safe zones and housing, schools etc for these people. I mean, honestly, I don't get why more Americans aren't being shipped out to other countries to help them out more often. The government needs to buy our plane tickets and mandate that we all help each other. Especially, the most wealthy countries in the world. I feel like if the wealthier countries got together and helped educate these poorer countries on how to protect themselves when a natural disaster strikes, that the child mortality rate would drop much more.
Chapter 2 - Plate Tectonics
Structure of the EarthThis is a file from the Wikimedia Commons.The most powerful forces on the planet are earthquakes and volcanoes. On December 26, 2004, the second most powerful earthquake in the last 100 years occurred off the coast of Indonesia creating a massive tsunami. Several volcanoes also erupted shortly afterward in the local region. By the end of the day, over 240,000 people had died. It is possible that the earthquake occurred because another one in Iran a year earlier, killing over 20,000 people, weakened the Asian fault. In October 2005, a powerful earthquake in Kashmir, India killed over 80,000 people. And just before 5 p.m. January 12, 2010, a magnitude 7.0 earthquake devastated the Caribbean nation of Haiti, leaving more than 250,000 dead, 300,000 wounded and more than one million people homeless. On March 11, 2011, Japan was rocked by a magnitude 9.0 earthquake followed by a devastating tsunami that killed over 30,000 people. So why do earthquakes and volcanoes occur? Is there a direct relationship between the two? In order to understand earthquakes and volcanoes, you have to understand the grander theory called Plate Tectonics.
The earth consists of three layers: an inner and outer core, the mantle, and two types of crust. The earth's core consists of two parts: a liquid outer core and a solid inner core, both made of iron and nickel from the early make-up of the planet where the temperatures can range from 8,600 degrees to 9,600 degrees Fahrenheit. The next and largest layer is called the mantle, which makes up two-thirds of Earth's mass. The mantle is actually called a plastic solid, which means it has the ability to flow very slowly. Heat from the earth's core causes the mantle to convect, like water over a stove but much slower, and it is the mantle's convection that is the driving force of plate tectonics.
The surface layer of the earth is called the crust and it makes up only 1 percent of Earth's mass. The crust is subdivided into two components: oceanic and continental crust. Again referring back to the image on the right, note that the oceanic crust is only about 3 miles thick, but is slightly more dense than continental crust. Most of this oceanic rock is called basalt and is a dark, dense rock.
Continental crust is much thicker than oceanic crust (averages between 20 to 25 miles thick), but is actually slightly less dense than oceanic crust. The main type of rock on continents is called granite. So if these two types of crust were to collide into each other, what do you think would happen to the oceanic crust? As a whole, notice that the crust is lighter than the mantle. It is sometimes said that the crust "floats" on the mantle like an iceberg in water and that is not too far from the truth and is called isostacy. Finally, the crust is the coldest, most rigid, and brittle layer with lots of folds and fractures.
Continental DriftImage copyright: (USGS) under Public Domain.In the early 1900s, a climatologist named Alfred Wegener proposed a hypothesis that at one time all of the continents were once together, creating a super-continent called Pangea, which later broke apart intoGondwanaland and Laurasia and finally the continents today. Over many years Wegner accumulated a lot of evidence to support his theory called continental drift. First, he noticed on world maps that the continents looked like large pieces of a world puzzle that could be put together to form a massive super-continent. Later he found similar plant and animal fossils on different continents separated by thousands of miles of oceans. He questioned how plants could and land species travel thousands of miles across the ocean to get to other continents; unless at one time all the continents were once together. Wegener also found climate evidence such as glaciation in the Sahara Desert and tropical fossils in Antarctica. Ultimately, Alfred Wegener believed that the crust was not as rigid as others believed, but actually flowed somehow. Yet he could not come up with a reason why the continents would move.
Plate Tectonics
Because Alfred Wegener could not propose a reason why continents would move, most of the scientific community never believed him before he died. It wasn't until the 1960s, during the Cold War, did technology finally catch up with Wegener's hypothesis. The United States military developed sonar as a way to look for Soviet submarines and in the process they discovered the largest mountain range in the world in the middle of the Atlantic Ocean, later called the mid-Atlantic ridge.
As more research was done to better understand the ocean floor, scientists discovered that the polar direction of magnetized rocks would reverse or flip symmetrical from the mid-Atlantic ridge, called paleomagnetism. At one point all the rocks are pointing toward magnetic north, followed by pointing toward magnetic south in the distant past, then magnetic north and so forth on equal sides of the mid-Atlantic ridge like a mirror image of each other. This proved that the earth's magnetic field has flipped several times throughout earth's history. Further research found that the youngest oceanic rocks exist near ocean ridges like the mid-Atlantic ridge and get older away from it.
All this evidence, including the data collected by Alfred Wegner's for this theory of continental drift, was put together to form the theory of plate tectonics. The theory states that the earth is made of several tectonic plates along with several smaller plates. Each tectonic plate consists of oceanic and continental crust. Scientists now realize that new oceanic rock is forming at these mid-oceanic ridges creating large mountain ranges. When this molten rock along the ridges rises to the Earth’s surface, the iron within them quickly points toward magnetic north (or magnetic south if the polarity has reversed) much like a compass before cooling into rock.
Image copyright: United States Geologic Survey licensed as Public Domain.
Image copyright: Creative Commons licensed as Public Domain.But if new oceanic rock is forming, and the earth is not growing, oceanic rock must be destroyed somewhere else. We now realize this occurs along the boundaries between lighter continental crust and denser oceanic crust. When the two collide, the heavier oceanic rock subducts underneath the lighter continental crust in a process called subduction. As the oceanic rock subducts downward, it can get locked up building large amounts of energy. Once the energy is too strong, the rock snaps free releasing that energy, called anearthquake. If the crust subducts deep enough, it may begin to melt into molten rock called magma. Magma is less dense than solid rock, so the magma rises to the surface to create volcanoes. So there is a direct relationship between earthquakes and volcanoes. In fact, the Ring of Fire in the Pacific Ocean consists of several subduction zones and is where 90 percent of all earthquakes and volcanoes occur.
Tectonic Plate Boundaries
There are three major types of tectonic plate boundares: convergent, divergent, and transform. Let's first look at convergent plate boundaries, which can be broken down into three subcategories.
Recall that oceanic crust is denser than continental rock like granite. Thus when two tectonic plates collide, the denser oceanic crust will subduct underneath the lighter continental crust. If the subducting rock becomes stuck, vast amounts of energy builds up. But once the pressure and energy is too great, the rock will rupture creating powerful earthquakes. As the subducted material sinks further, it will begin to melt under great heat and pressure, becoming less dense as it melts, and rise up as magma to form dangerous composite volcanoes. Mountain ranges created by oceanic-to-continental convergence are the Andes mountains in South America, the Cascades in the western United States, and the Ring of Fire in the Pacific Ocean.
Below is a Google Earth image showing a series of oceanic-to-oceanic subduction zones within the Pacific Ring of Fire. You can visibily see the subduciton zones that create the volcanic and powerful Aleutian Islands and the converging subduction plates that make of volcanic islands of Japan.
With oceanic-to-oceanic convergence, the heavier of the two will subduct down beneath the other. Just like continental-to-oceanic convergence, this plate boundary can generate powerful earthquakes and volcanoes; but instead of volcanoes on land, volcanic islands form such as Japan, the Aleutian Islands of Alaska, and Indonesia. The great earthquake in Indonesia in 2004, which produced the devastating tsunami, was created by this process along with the 2011 earthquake and tsunami in Japan.
When two continental plates converge, instead of subduction, the two similar tectonic plates will buckle up to create large mountain ranges like a massive car pile-up. This is called continental-to-continental convergence, and geologically creates intense folding and faulting rather than volcanic activity. Examples of mountain ranges created by this process are the Himalayan mountains (taken from the International Space Station) as India is colliding with Asia, the Alps in Europe, and the Appalacian mountains in the United States as the North American plate collided with the African plate when Pangea was forming. The Kashmir India earthquake of 2005 that killed over 80,000 people occurred because of this process. And most recently, the 2008 earthquake in China which killed nearly 85,000 people before the Summer Olympics was because of this tectonic force.
When convection within the mantel causes two tectonic plates move away from each other, or when a tectonic plate tears itself apart, divergent boundaries can form. As divergence occurs, shallow earthquakes can occur along with volcanoes along the rift areas. When the process begins, a valley will develop such as the Great Rift Valley in Africa. Over time that valley can fill up with water creating linear lakes. If divergence continues, a sea can form like the Red Sea and finally an ocean like the Atlantic Ocean. Check out the eastern half of Africa and notice the lakes that look linear. Eastern Africa is tearing apart from these linear lakes, to the Great Rift Valley, and up to the Red Sea. Notice how the Red Sea looks like it could be put back together again. The ultimate divergent boundary is the Atlantic Ocean, which began when Pangea broke apart.
Below are two satellite images using Google Earth, both focusing on parts of Africa. On the left yo can see rift valleys that have filled in with water to form linear lakes. On the right in northern Africa, you can see the Red Sea with a rift valley in the center, which use to be a linear lake that grew into a sea. If the Red Sea continues to grow, it could form an ocean similar to the Atlantic Ocean with the mid-Atlantic Ridge.
Transform boundaries occurs when two tectonic plates slide (or grind) past parallel to each other. The most famous transform boundary is the San Andreas Fault where the Pacific plate (that Los Angeles and Hawaii are on) is grinding past the North American plate (that San Francisco and the rest of the United States is on) at the rate of 3 inches a year. Recently, geologists have stated that San Francisco should expect another disastrous earthquake in the next 30 years. Another important transform boundary is the North Anatolian Fault in Turkey. This powerful fault last ruptured in 1999 in Izmit, Turkey which killed 17,000 people in 48 seconds.
Comparison of the San Andreas Fault, CA and the North Anatolian Fault in Turkey. Both are located along transform boundaries. Image source: United States Geologic Survey (USGS).
San Andreas Fault
Below is an interesting video from National Geographic called Colliding Continents. It takes a hypothetical situation of humans coming back to Earth in the distant future and uses the idea of Plate Tectonics to understand the past.
The earth consists of three layers: an inner and outer core, the mantle, and two types of crust. The earth's core consists of two parts: a liquid outer core and a solid inner core, both made of iron and nickel from the early make-up of the planet where the temperatures can range from 8,600 degrees to 9,600 degrees Fahrenheit. The next and largest layer is called the mantle, which makes up two-thirds of Earth's mass. The mantle is actually called a plastic solid, which means it has the ability to flow very slowly. Heat from the earth's core causes the mantle to convect, like water over a stove but much slower, and it is the mantle's convection that is the driving force of plate tectonics.
The surface layer of the earth is called the crust and it makes up only 1 percent of Earth's mass. The crust is subdivided into two components: oceanic and continental crust. Again referring back to the image on the right, note that the oceanic crust is only about 3 miles thick, but is slightly more dense than continental crust. Most of this oceanic rock is called basalt and is a dark, dense rock.
Continental crust is much thicker than oceanic crust (averages between 20 to 25 miles thick), but is actually slightly less dense than oceanic crust. The main type of rock on continents is called granite. So if these two types of crust were to collide into each other, what do you think would happen to the oceanic crust? As a whole, notice that the crust is lighter than the mantle. It is sometimes said that the crust "floats" on the mantle like an iceberg in water and that is not too far from the truth and is called isostacy. Finally, the crust is the coldest, most rigid, and brittle layer with lots of folds and fractures.
Continental DriftImage copyright: (USGS) under Public Domain.In the early 1900s, a climatologist named Alfred Wegener proposed a hypothesis that at one time all of the continents were once together, creating a super-continent called Pangea, which later broke apart intoGondwanaland and Laurasia and finally the continents today. Over many years Wegner accumulated a lot of evidence to support his theory called continental drift. First, he noticed on world maps that the continents looked like large pieces of a world puzzle that could be put together to form a massive super-continent. Later he found similar plant and animal fossils on different continents separated by thousands of miles of oceans. He questioned how plants could and land species travel thousands of miles across the ocean to get to other continents; unless at one time all the continents were once together. Wegener also found climate evidence such as glaciation in the Sahara Desert and tropical fossils in Antarctica. Ultimately, Alfred Wegener believed that the crust was not as rigid as others believed, but actually flowed somehow. Yet he could not come up with a reason why the continents would move.
Plate Tectonics
Because Alfred Wegener could not propose a reason why continents would move, most of the scientific community never believed him before he died. It wasn't until the 1960s, during the Cold War, did technology finally catch up with Wegener's hypothesis. The United States military developed sonar as a way to look for Soviet submarines and in the process they discovered the largest mountain range in the world in the middle of the Atlantic Ocean, later called the mid-Atlantic ridge.
As more research was done to better understand the ocean floor, scientists discovered that the polar direction of magnetized rocks would reverse or flip symmetrical from the mid-Atlantic ridge, called paleomagnetism. At one point all the rocks are pointing toward magnetic north, followed by pointing toward magnetic south in the distant past, then magnetic north and so forth on equal sides of the mid-Atlantic ridge like a mirror image of each other. This proved that the earth's magnetic field has flipped several times throughout earth's history. Further research found that the youngest oceanic rocks exist near ocean ridges like the mid-Atlantic ridge and get older away from it.
All this evidence, including the data collected by Alfred Wegner's for this theory of continental drift, was put together to form the theory of plate tectonics. The theory states that the earth is made of several tectonic plates along with several smaller plates. Each tectonic plate consists of oceanic and continental crust. Scientists now realize that new oceanic rock is forming at these mid-oceanic ridges creating large mountain ranges. When this molten rock along the ridges rises to the Earth’s surface, the iron within them quickly points toward magnetic north (or magnetic south if the polarity has reversed) much like a compass before cooling into rock.
Image copyright: United States Geologic Survey licensed as Public Domain.
Image copyright: Creative Commons licensed as Public Domain.But if new oceanic rock is forming, and the earth is not growing, oceanic rock must be destroyed somewhere else. We now realize this occurs along the boundaries between lighter continental crust and denser oceanic crust. When the two collide, the heavier oceanic rock subducts underneath the lighter continental crust in a process called subduction. As the oceanic rock subducts downward, it can get locked up building large amounts of energy. Once the energy is too strong, the rock snaps free releasing that energy, called anearthquake. If the crust subducts deep enough, it may begin to melt into molten rock called magma. Magma is less dense than solid rock, so the magma rises to the surface to create volcanoes. So there is a direct relationship between earthquakes and volcanoes. In fact, the Ring of Fire in the Pacific Ocean consists of several subduction zones and is where 90 percent of all earthquakes and volcanoes occur.
Tectonic Plate Boundaries
There are three major types of tectonic plate boundares: convergent, divergent, and transform. Let's first look at convergent plate boundaries, which can be broken down into three subcategories.
Recall that oceanic crust is denser than continental rock like granite. Thus when two tectonic plates collide, the denser oceanic crust will subduct underneath the lighter continental crust. If the subducting rock becomes stuck, vast amounts of energy builds up. But once the pressure and energy is too great, the rock will rupture creating powerful earthquakes. As the subducted material sinks further, it will begin to melt under great heat and pressure, becoming less dense as it melts, and rise up as magma to form dangerous composite volcanoes. Mountain ranges created by oceanic-to-continental convergence are the Andes mountains in South America, the Cascades in the western United States, and the Ring of Fire in the Pacific Ocean.
Below is a Google Earth image showing a series of oceanic-to-oceanic subduction zones within the Pacific Ring of Fire. You can visibily see the subduciton zones that create the volcanic and powerful Aleutian Islands and the converging subduction plates that make of volcanic islands of Japan.
With oceanic-to-oceanic convergence, the heavier of the two will subduct down beneath the other. Just like continental-to-oceanic convergence, this plate boundary can generate powerful earthquakes and volcanoes; but instead of volcanoes on land, volcanic islands form such as Japan, the Aleutian Islands of Alaska, and Indonesia. The great earthquake in Indonesia in 2004, which produced the devastating tsunami, was created by this process along with the 2011 earthquake and tsunami in Japan.
When two continental plates converge, instead of subduction, the two similar tectonic plates will buckle up to create large mountain ranges like a massive car pile-up. This is called continental-to-continental convergence, and geologically creates intense folding and faulting rather than volcanic activity. Examples of mountain ranges created by this process are the Himalayan mountains (taken from the International Space Station) as India is colliding with Asia, the Alps in Europe, and the Appalacian mountains in the United States as the North American plate collided with the African plate when Pangea was forming. The Kashmir India earthquake of 2005 that killed over 80,000 people occurred because of this process. And most recently, the 2008 earthquake in China which killed nearly 85,000 people before the Summer Olympics was because of this tectonic force.
When convection within the mantel causes two tectonic plates move away from each other, or when a tectonic plate tears itself apart, divergent boundaries can form. As divergence occurs, shallow earthquakes can occur along with volcanoes along the rift areas. When the process begins, a valley will develop such as the Great Rift Valley in Africa. Over time that valley can fill up with water creating linear lakes. If divergence continues, a sea can form like the Red Sea and finally an ocean like the Atlantic Ocean. Check out the eastern half of Africa and notice the lakes that look linear. Eastern Africa is tearing apart from these linear lakes, to the Great Rift Valley, and up to the Red Sea. Notice how the Red Sea looks like it could be put back together again. The ultimate divergent boundary is the Atlantic Ocean, which began when Pangea broke apart.
Below are two satellite images using Google Earth, both focusing on parts of Africa. On the left yo can see rift valleys that have filled in with water to form linear lakes. On the right in northern Africa, you can see the Red Sea with a rift valley in the center, which use to be a linear lake that grew into a sea. If the Red Sea continues to grow, it could form an ocean similar to the Atlantic Ocean with the mid-Atlantic Ridge.
Transform boundaries occurs when two tectonic plates slide (or grind) past parallel to each other. The most famous transform boundary is the San Andreas Fault where the Pacific plate (that Los Angeles and Hawaii are on) is grinding past the North American plate (that San Francisco and the rest of the United States is on) at the rate of 3 inches a year. Recently, geologists have stated that San Francisco should expect another disastrous earthquake in the next 30 years. Another important transform boundary is the North Anatolian Fault in Turkey. This powerful fault last ruptured in 1999 in Izmit, Turkey which killed 17,000 people in 48 seconds.
Comparison of the San Andreas Fault, CA and the North Anatolian Fault in Turkey. Both are located along transform boundaries. Image source: United States Geologic Survey (USGS).
San Andreas Fault
Below is an interesting video from National Geographic called Colliding Continents. It takes a hypothetical situation of humans coming back to Earth in the distant future and uses the idea of Plate Tectonics to understand the past.
This chapter focuses closely on Earthquakes and Volcanos and Human rights. The Scholarly Article I chose was in relation to the Haiti Earthquake and a very interesting survey that was done before and after the Earthquake. Titled, Mortality, crime and access to basic needs before and after the Haiti earthquake: a random survey of Port-au-Prince households.
A link to this article is: http://www.tandfonline.com/doi/abs/10.1080/13623699.2010.535279#.VP5uTWTF8mU
An example of the questions the people of Haiti were asked prior to the Earthquake were in regards to food, medical and mortality. They surveyed 1,800 households in 2009, with a response rate of 90%. Then in 2010 there were 93% interviewed. The result revealed that, 158,679 people within the six week period following the Haiti Earthquake had died. This revealed that they had died, had been sexually assaulted, had lack of shelter which resulted in death, and even starvation. To this day survivors of the Haiti earthquake in Port au Prince continue to suffer from starvation and sexual assault.
This survey on the people of Haiti and their lack of supplies as a Human Right, helps bring to light how important these things really are and how they affect people so severly. For example, because of the lack of policing, food and supplies. These people were forced to live in a sort of imprisonment after the Earthquake, which proved a much more severe surrounding. They had to fight for everything they had, even prior to the Earthquake, however, afterwards they were forced to live in a sort of Anarchy type of environment. They had nothing, so as a result, they had nothing to lose. This is where the violence and sexual assaults increased far more than they ever had in the past. Starvation and lack of medical supplies, as well as all of the deaths that took place, resulted in the mentality of, "I have nothing left, so I have nothing to lose" Port au prince has since began to reconstruct it's self as a community, however the hurt, and struggles, lives lost, sexual assault and massive hunger will remain within their imaginations. A struggle, still being faced, but fading slowly, the people of Port au prince will soon never forget.
This chapter was a very informative one. I was pleasantly surprised by the amount of empathy evoked, and knowledge gained learning about plate tectonics. I was able to put myself in these peoples shoes and to really begin to understand their struggles and the severity of this sort of natural disaster. One of the things I learned from this chapter was from reading the Human Rights watch. Below is from Chapter 2, in regards to the education I gained from reading the Human rights watch:
I viewed the US behind bars photo essay. My response to that one would be that, as I understand that hard sentences can reflect a lot of older people in Prisons who are ill and require a lot of free health care and medication. We cannot release murderers and rapists out into the world regardless of how old they are. I agree that there are a lot of people who should not be in prison, and even more who have been in prison way too long for petty crimes, such as an old attempt to sell marijuana crime, which should not be labeled a Schedule I drug alongside Heroin and Crystal Meth, which are two that justifiably should be. Regardless, the article stated that these prisoners are too old and infirm to remain in prison. This may be true to a degree, however I don’t believe that we can guarantee that someone is too old to commit another crime. I feel like, we can maybe move these older prisoners to a halfway house for the old and sick, which would basically be a low security prison. Another reason we shouldn’t just release these people is that, they then become societies problem as opposed to the State Prisons problem, where intern they receive free healthcare and whatever else they need in order to be functional. We cannot assume that these old, infirm jail birds are, while they are too sick to be in prison won’t be too old and infirm to go out ad get a job as a wal-mart greeter so that they can pay for their studio apartments, groceries, and utility bills with the zero dollars they have in their retirement savings. I would say the genre of this photo essay was to persuade people to feel for these elderly cons and take action.
The second one I watched was Mali: Child Labor and Mercury Use in Artisanal Gold Mining (Links to an external site.) - I feel like this genre was informative, but more directed toward external countries who are purchasing this gold, as opposed to others living in Mali as well as human rights activists. I honestly feel like this one reminded me a lot of the movie, Blood Diamond. I say that because, like in the movie, there are innocent, poverty stricken African Americans filling up buckets with diamonds, and many of these people are treated very poorly and paid very little. As is the case with these children of Mali; they are collecting gold and touching as well as breathing in poisonous mercury— and for what? Sure they are making maybe 3 cents a day, but you can’t get more selfish of a society of people who would rather send 6 year old poverty stricken children out to play in the mercury and collect gold for all of the rich white folk in other countries who all ready have way more than they need to survive. This article makes me nauseous and embarrassed for humanity.
A link to this article is: http://www.tandfonline.com/doi/abs/10.1080/13623699.2010.535279#.VP5uTWTF8mU
An example of the questions the people of Haiti were asked prior to the Earthquake were in regards to food, medical and mortality. They surveyed 1,800 households in 2009, with a response rate of 90%. Then in 2010 there were 93% interviewed. The result revealed that, 158,679 people within the six week period following the Haiti Earthquake had died. This revealed that they had died, had been sexually assaulted, had lack of shelter which resulted in death, and even starvation. To this day survivors of the Haiti earthquake in Port au Prince continue to suffer from starvation and sexual assault.
This survey on the people of Haiti and their lack of supplies as a Human Right, helps bring to light how important these things really are and how they affect people so severly. For example, because of the lack of policing, food and supplies. These people were forced to live in a sort of imprisonment after the Earthquake, which proved a much more severe surrounding. They had to fight for everything they had, even prior to the Earthquake, however, afterwards they were forced to live in a sort of Anarchy type of environment. They had nothing, so as a result, they had nothing to lose. This is where the violence and sexual assaults increased far more than they ever had in the past. Starvation and lack of medical supplies, as well as all of the deaths that took place, resulted in the mentality of, "I have nothing left, so I have nothing to lose" Port au prince has since began to reconstruct it's self as a community, however the hurt, and struggles, lives lost, sexual assault and massive hunger will remain within their imaginations. A struggle, still being faced, but fading slowly, the people of Port au prince will soon never forget.
This chapter was a very informative one. I was pleasantly surprised by the amount of empathy evoked, and knowledge gained learning about plate tectonics. I was able to put myself in these peoples shoes and to really begin to understand their struggles and the severity of this sort of natural disaster. One of the things I learned from this chapter was from reading the Human Rights watch. Below is from Chapter 2, in regards to the education I gained from reading the Human rights watch:
I viewed the US behind bars photo essay. My response to that one would be that, as I understand that hard sentences can reflect a lot of older people in Prisons who are ill and require a lot of free health care and medication. We cannot release murderers and rapists out into the world regardless of how old they are. I agree that there are a lot of people who should not be in prison, and even more who have been in prison way too long for petty crimes, such as an old attempt to sell marijuana crime, which should not be labeled a Schedule I drug alongside Heroin and Crystal Meth, which are two that justifiably should be. Regardless, the article stated that these prisoners are too old and infirm to remain in prison. This may be true to a degree, however I don’t believe that we can guarantee that someone is too old to commit another crime. I feel like, we can maybe move these older prisoners to a halfway house for the old and sick, which would basically be a low security prison. Another reason we shouldn’t just release these people is that, they then become societies problem as opposed to the State Prisons problem, where intern they receive free healthcare and whatever else they need in order to be functional. We cannot assume that these old, infirm jail birds are, while they are too sick to be in prison won’t be too old and infirm to go out ad get a job as a wal-mart greeter so that they can pay for their studio apartments, groceries, and utility bills with the zero dollars they have in their retirement savings. I would say the genre of this photo essay was to persuade people to feel for these elderly cons and take action.
The second one I watched was Mali: Child Labor and Mercury Use in Artisanal Gold Mining (Links to an external site.) - I feel like this genre was informative, but more directed toward external countries who are purchasing this gold, as opposed to others living in Mali as well as human rights activists. I honestly feel like this one reminded me a lot of the movie, Blood Diamond. I say that because, like in the movie, there are innocent, poverty stricken African Americans filling up buckets with diamonds, and many of these people are treated very poorly and paid very little. As is the case with these children of Mali; they are collecting gold and touching as well as breathing in poisonous mercury— and for what? Sure they are making maybe 3 cents a day, but you can’t get more selfish of a society of people who would rather send 6 year old poverty stricken children out to play in the mercury and collect gold for all of the rich white folk in other countries who all ready have way more than they need to survive. This article makes me nauseous and embarrassed for humanity.
Chapter 3 - Earthquakes
Chapter 3: EarthquakesEarthquakes are serious natural hazards that affect people across the globe, sometimes at long distances from where the quakes occur. They are especially dangerous because seismologists, the scientists who study earthquakes, cannot predict them in time for evacuations or other precautions. Your goals in this module should be to:
3.1 Earthquake Basics
Image copyright: United Nations Development Programme, licensed as Creative Commons Public Domain.
An earthquake is a sudden motion or trembling in the earth caused by the abrupt release of slowly accumulated energy. All earthquakes occur along a fault, which is a fracture in the earth's crust where tectonic movement occurs. Where the actual break occurred along the fault is called the focus (also called the hypocenter) and the epicenter is the point on the Earth's surface that lies directly above the focus and is where the strongest shockwave is normally felt. Click here to watch a brief video on earthquakes.
Recall that all around the planet, tectonic plates are moving because of convection in the mantle. Tectonic plates are also composed of two types of crust, oceanic and continental. The oceanic crust, which is made mostly of basalt is more dense than continental crust that is made of granite. When these tectonic plates come in contact, the denser oceanic crust subducts below the continental crust. Now sometimes when two tectonic plate come in contact they become stuck. As the rocks begin to bend or strain under tectonic forces, large amounts of energy - called strain - builds. When the stress becomes too great for the rocks to hold, segments may suddenly snap, releasing large amounts of energy. This is called theelastic rebound theory.
Movement along a fault can occur vertically or horizontally. The greatest horizontal displacement was 21 feet along the San Andreas Fault in the Great San Francisco Quake of 1906. Imagine in an instant being moved 21 feet horizontally! The greatest maximum vertical displacement used to be the Alaskan earthquake in 1964. The vertical displacement was 33 feet! But on December 26, 2004 a 9.1 underwater earthquake occurred in Indonesia. It had a vertical displacement of 60 feet over 800 miles long! Imaging being thrown 60 feet instantly and that it occurred for 800 miles. The compression caused by the oceanic-oceanic convergence actually sped up the earth's rotation 2.676 millionths of a second and shifted the axis 1 inch! It produced a massive tsunami traveling 500 mph. Over 240,000 died from the earthquake and tsunami; one in three were children. The image below if of an earthquake in Pakistan that killed 80,000.
Editor's Note....
3.2 Types of EarthquakesThere are several types of faults that earthquakes occur on, which are dependent on whether the fault is occurring because of convergent, divergent, or transform tectonic plate forcing. Geologists use old mining terms to distinguish between different types of faults. Think of a minor walking down into the earth along a fault line. The ground the miner is walking on is called the footwall. If the minor needs to hand their lantern, the ceiling is called the hanging-wall.
Strike-slip faults (A) occur along transform boundaries where tectonic plates are moving horizontal or parallel to each other. Deformation of rivers, roads, fences, etc. can occur if they cross over these fault lines. Examples of strike-slip faults are the San Andreas Fault in the United States and the North Anatolian Fault in Turkey.
Normal faults (B) are common along divergent plate boundaries. As extensional forces occur, the footwall is forced upward, while the hanging wall slides downward. This can create a series of valleys (called a graben) and mountains (called a horst). Examples of mountain ranges and valleys created by normal faulting are theGrand Tetons, the Basin and Range in the western United States, and the Wasatch Front in Utah.
Reverse faults (C) are caused by compressional forces as tectonic plates collide together forcing one plate to rise above another. Using the mining terminology, movement along a reverse fault would cause the hanging-wall to rise up and the footwall to drop lower. The angle of a reverse fault is about 45 degrees, but if the angle of the fault is steeper than 45 degrees it is called a thrust fault. When two plates collide, intense folding and faulting can occur. Examples of where reverse and thrust faults occur are where convergent boundaries are common such as: the Northern Rocky Mountains, the Alps, Himalayas, and the Appalachian mountains.
Image copyright: United States Geologic Survey, licensed as Creative Commons Public Domain.
3.3 Measuring Seismic Activity
Seismologists record seismic waves using a seismograph. When a rupture occurs within the earth, energy is released from the focus in all directions and the seismograph will record the magnitude of the energy. There are three types of seismic waves: P-waves, S-waves, and Surface waves.
Primary waves, also called P-waves, are compressional waves and are the first to be felt by seismographs and individuals because they travel the fastest (about 3.7 miles per second). To visualize a P-wave, think of stretching a slinky and letting it go. You would be able to actually see the compression occurring within the slinky.
The second type of seismic wave is called a secondary wave or S-wave. They reach the seismograph second because they travel slower than P-waves and travel in a side-to-side manner. Imaging pulling a slinky and shaking one end side to side. You would be able to see the side-to-side movement travel up the slinky. P-waves and S-waves together are called body waves because they travel through the earth rather than on the surface.
Surface waves are the last seismic waves to reach an area, create the greatest ground motion, and are the most destructive because they are the slowest and move in a rolling manner.
Image copyright: United States Geologic Survey, licensed as Creative Commons Public Domain.
3.4 Locating Seismic Activity
Image copyright: United States Geologic Survey, licensed as Creative Commons Public Domain.
In order to determine the location of an earthquake, seismologists must measure the interval distance of P-waves and S-waves released during the rupture. P-waves travel faster than S-waves, thus scientists calculate the time difference between both waves to determine a perimeter of the epicenter. But the epicenter could be anywhere within that perimeter. Therefore, scientists must use a minimum of three seismic readings from different seismograph stations in order to determine the exact location of the epicenter.
3.5 Classifying Earthquakes
Image copyright: Licensed as Creative Commons Public Domain.
There are two basic ways to measure the strength and destructive power of an earthquake. The first is called the Richter scale. Based on a range from 1 (weakest) to 10 (strongest), the Richter scale measures the magnitude (energy released) by an earthquake. The scale is logarithmic meaning that every whole number increase in magnitude is 10 times more ground shaking and 30 times more energy released. Example: a magnitude 7.0 earthquake has ground shaking 10 times more than a 6.0 and 30 times more energy released. A magnitude 8.0 earthquake has ground shaking 100 times more than a 6.0 and 900 times more energy released. The December 26, 2004 Indonesian earthquake had a magnitude of 9.1. It should be noted that for the strongest earthquakes, the Richter Scale is no longer used. Instead, the Moment Magnitude Scaleis used, though it is very similar to the Richter Scale. The Richter Scale and Moment Magnitude Scale provide quantitative information of the energy released from an earthquake.
The Modified Mercalli Intensity Scale (shown below) is more qualitative and focuses on the actual damage caused by the earthquake and its impact on human lives and property. The scale has 12 categories ranging from I (felt by very few people) to XII (total destruction). Each category is based on a description of how people felt or perceived the earthquake. The major problem with the Modified Mercalli Intensity Scale is that ground damage is relative to location. The scale can be influenced by the types of rocks underneath, if the ground is mostly bedrock, loose sediment, or even landfill, how well buildings are built, and how far away the people and buildings are from the epicenter. The farther away from the epicenter, the weaker the earthquake will feel. So the Modified Mercalli Intensity Scale is great to determine ground damage and how the earthquake affected people, but does not tell you how much energy was actually released from the rupture. Because of the access to the Internet, the United States Geologic Survey (USGS) allows you to email them if you just felt and earthquake. They take this information and create a map similar to the Modified Mercalli maps, but call it a shake map. To view real-time shake maps from the USGS, click here. For a list of recent earthquakes in Utah along with shake maps, check out the Seismology Departmentat the University of Utah.
Image copyright: United States Geologic Survey, licensed as Creative Commons Public Domain.
One final note, with the recent popularity of smart phones and the iTouch, there are several apps now available in relation to natural disasters. In terms of earthquakes, a highly popular app in Apple's iTunes is called QuakeWatch. There are probably similar apps for other smart phone devises.
3.6 Earthquake Hazards
Image copyright: United Nations Development Program, licensed as Creative Commons Public Domain.
Earthquakes do not kill people; falling buildings and highways kill people. History has taught us the importance of building codes to create safer buildings. Many of the massive death tolls reported by earthquakes are caused by poorly built buildings rather than the earthquake itself. In general, buildings or structures built out of brick, stone, mud, or reinforced concrete fair poorly in large earthquakes because there is very little flexibility in the structures as the ground shakes. The best types of buildings to be in are those built of wood because of there flexibility; the house may not be habitable after the earthquake, but they won't crumble or collapse on people. Buildings with weak floors or basement garages are also susceptible to collapsing.
There are several techniques engineers have developed to help buildings withstand the destructive power of earthquakes. Many buildings are being built or retrofitted with diagonal braces that can withstand the ground motions caused by an earthquake. Tall buildings also tend to sway at different frequencies them to slam into each other during an earthquake. If engineers know how much a building will sway, they can determine how far apart buildings must be built. Finally, engineers are placing rubber pads at the base of newly built and retrofitted buildings that act as shock absorbers.
Liquefaction can occur when earthquakes rupture in regions with loose sediment and high water tables. As the ground shakes, the high water table rises to the surface which softens and destabilizes the surface causing structures to break off their foundations or fall over. Liquefaction has occurred in Mexico City in 1985, San Francisco 1989, Anchorage, Alaska 1964, Kobe Japan in 1995 and will occur in Salt Lake City.
Image copyright: This work is in the public domain in that it was published in the United States between 1923 and 1977 and without a copyright notice.
Click here to see a map of liquefaction potential and ground shaking within Salt Lake County. (You can also look at maps for Tooele, Cache, Davis, Weber and Utah Counties.) For those who live in the Salt Lake valley, notice how the liquefaction potential is greatest along the Jordan River and near the Great Salt Lake. Any ideas why? It has to do with the fact the water table is highest near those areas. So when an earthquake occurs and the ground begins to shake, the water will rise and destabilize the ground. In these maps, the reds and purples represent the areas of greatest liquefaction potential from a magnitude 7.0 earthquake.
Earthquakes can also destabilize steep slopes causing them to slip and fail. These landslides tend to occur where the ground is mostly loose sandy soil with a high water table. Fires are also another serious hazard created by earthquakes as our infrastructure collapses and electrical and gas lines break. The treat of fires will also increase as emergency crews have a hard time maneuvering through the debris. There are two simple things individuals can do to reduce their risk of a fire: first is to have a wrench attached to their outside gas line. If you smell gas at your house, quickly turn off the gas. But if you do not smell gas, do not turn it off; doing so may prevent you from having heating in your house in the winter and it may be months before it gets turned back on. Second, make sure your water heater is attached to your house. A simple $20 bracket wrapped around your water heater and bolted into your house may prevent it from falling over and breaking its gas line.
Another interesting effect of powerful earthquakes is island creation. In September 2013, a moderately powerful earthquake off the coast of Pakistan created a 200 foot wide, 60 foot tall island. It won't last long because ocean waves will erode it back down, but it's an interesting and rare effect of earthquakes. Click here to learn more.
3.7 Human-Induced EarthquakesCan humans create earthquakes? Maybe not intentionally, but the answer is yes and here is why. If a water reservoir is built on top of an active fault line, the water may actually lubricate the fault and weaken the stress built up within it. This may either create a series of small earthquakes or potentially create a large earthquake. Also the shear weight of the reservoir's water can weaken the bedrock causing it to fracture. Then the obvious concern is if the dam fails. Earthquakes can also be generated if humans inject other fluids into a fault such as sewage or chemical waste. Finally, nuclear explosions can trigger earthquakes. In fact, one way to determine if a nation has tested a nuclear bomb is by monitoring the earthquakes and energy released by the explosion.
3.8 Earthquake PrepardenessEverywhere in the world has disasters, so nowhere is safe. But everyone should be prepared for the type of disasters their region experiences. Everyone should have a 72 hour kit prepared in your car and house. Recently the Federal Emergency Management Agency (FEMA) stated that citizens should prepare a 5-day kit in case federal, state, and local agencies can not reach you. Learn more how you can prepare at Ready.gov. Here are a few more items you should think about with disaster preparedness.
This chapter was about Earthquakes.
The crust of the earth is a very thin layer and underneath that is the center which consists of hot melted rock, which is as hot as up to 3,500 degrees. The hot rocks are on the bottom and the cooler rocks are at the top which shoves into the earths crust. Once the rocks push against the earth they create plates, and the plates, they are constantly moving and rubbing against each other and fall under the other one, once the stress builds up the earth begins to shift and shake and an earthquake begins. 100,000 earthquakes happen every year with a total of 10,000 deaths and only one thousand earthquake a year are severe enough to actually feel.
I was surprised to learn that the Haiti earthquake left one of the highest death tolls. I never would have guessed that. Which chapter impacted you the most? All the death, and the lady in the beginning who talked about how her house fell on her baby. It’s so unreal to think about these kinds of things literally happening. It always makes me wonder how we here in Utah would react. If we would come together as these people in Haiti, or if it would be a one for himself free for all. Why? It’s just, it seems unrealistic to read about so many people dying all over the place in such a short amount of time and the lady whose baby died and was crushed by her house, just put the most horrifying visuals in my brain. It’s just so sad. these people who survived are such strong willed people. Cite at least 2 passages that seemed significant to you. The first one was, Getro Nelio who was 25. He watched his father die in front of him instead of going to save his dad, he decided to save 28 more people. Granted, his dad was going to die anyway, it must have took some real emotional strength, to just leave him there, knowing he was going to die anyway and to go save 28 more people. I guess, I would want that as well. If it were me dying as his dad was, if I was going to die anyway, or if not saving me, would save 28 more people. It just makes more sense that way.
The other story I really liked was, the story of how police and rescue disappeared seconds after the incident. That for many reasons like they were dead, or they could not reach their supplies of that, they just took off, that they were not around. So instead, the local survivors worked together and formed to help and assist people who were left for dead. I also thought that it was kind of a low blow for the rescue teams that did exist, that they immediately aided the rich and the foreigners. Granted, they are not from there, but the fact that they were staying at a fancy hotel and are from somewhere else or have more money, should not make the final decision on who gets to live or be helped first and who does not. Earth is constantly changing shape slowly, eventually the oceans will change and the continents will crash into each other, creating entirely new continents and new ocean areas, as well as new mountainous areas.
In terms of Human Rights, I feel like people should be allowed the right to be able to live in homes and be in businesses that have a safely built foundation and do not have to worry about the possibility of their baby getting crushed to death because a building fell on it. We are living in a time where people should have more of a possibility of living through natural disasters because of the technological advancements the world is constantly coming together with more opportunities for earthquake safe buildings and natural disaster safe environments. However, we need to come together as a world and take care of each other financially in terms of natural disaster safety, instead of being there to help with the damage after the fact.
- understand how scientists measure and compare earthquakes.
- be familiar with processes that take place in an earthquake such as faulting, tectonic creep, and seismic waves.
- know which global regions are most at risk for earthquakes and shy they are at risk.
- know and understand the effects of earthquakes, including shaking, ground rupture, and liquefaction, as well as how earthquakes are linked to other natural hazards such as landslides, fires, and tsunamis.
- know the important natural service functions of earthquakes.
- know how human beings interact with and affect the earthquake hazard.
- understand how we can minimize seismic risk, and recognize adjustments we can make to protect ourselves.
3.1 Earthquake Basics
Image copyright: United Nations Development Programme, licensed as Creative Commons Public Domain.
An earthquake is a sudden motion or trembling in the earth caused by the abrupt release of slowly accumulated energy. All earthquakes occur along a fault, which is a fracture in the earth's crust where tectonic movement occurs. Where the actual break occurred along the fault is called the focus (also called the hypocenter) and the epicenter is the point on the Earth's surface that lies directly above the focus and is where the strongest shockwave is normally felt. Click here to watch a brief video on earthquakes.
Recall that all around the planet, tectonic plates are moving because of convection in the mantle. Tectonic plates are also composed of two types of crust, oceanic and continental. The oceanic crust, which is made mostly of basalt is more dense than continental crust that is made of granite. When these tectonic plates come in contact, the denser oceanic crust subducts below the continental crust. Now sometimes when two tectonic plate come in contact they become stuck. As the rocks begin to bend or strain under tectonic forces, large amounts of energy - called strain - builds. When the stress becomes too great for the rocks to hold, segments may suddenly snap, releasing large amounts of energy. This is called theelastic rebound theory.
Movement along a fault can occur vertically or horizontally. The greatest horizontal displacement was 21 feet along the San Andreas Fault in the Great San Francisco Quake of 1906. Imagine in an instant being moved 21 feet horizontally! The greatest maximum vertical displacement used to be the Alaskan earthquake in 1964. The vertical displacement was 33 feet! But on December 26, 2004 a 9.1 underwater earthquake occurred in Indonesia. It had a vertical displacement of 60 feet over 800 miles long! Imaging being thrown 60 feet instantly and that it occurred for 800 miles. The compression caused by the oceanic-oceanic convergence actually sped up the earth's rotation 2.676 millionths of a second and shifted the axis 1 inch! It produced a massive tsunami traveling 500 mph. Over 240,000 died from the earthquake and tsunami; one in three were children. The image below if of an earthquake in Pakistan that killed 80,000.
Editor's Note....
3.2 Types of EarthquakesThere are several types of faults that earthquakes occur on, which are dependent on whether the fault is occurring because of convergent, divergent, or transform tectonic plate forcing. Geologists use old mining terms to distinguish between different types of faults. Think of a minor walking down into the earth along a fault line. The ground the miner is walking on is called the footwall. If the minor needs to hand their lantern, the ceiling is called the hanging-wall.
Strike-slip faults (A) occur along transform boundaries where tectonic plates are moving horizontal or parallel to each other. Deformation of rivers, roads, fences, etc. can occur if they cross over these fault lines. Examples of strike-slip faults are the San Andreas Fault in the United States and the North Anatolian Fault in Turkey.
Normal faults (B) are common along divergent plate boundaries. As extensional forces occur, the footwall is forced upward, while the hanging wall slides downward. This can create a series of valleys (called a graben) and mountains (called a horst). Examples of mountain ranges and valleys created by normal faulting are theGrand Tetons, the Basin and Range in the western United States, and the Wasatch Front in Utah.
Reverse faults (C) are caused by compressional forces as tectonic plates collide together forcing one plate to rise above another. Using the mining terminology, movement along a reverse fault would cause the hanging-wall to rise up and the footwall to drop lower. The angle of a reverse fault is about 45 degrees, but if the angle of the fault is steeper than 45 degrees it is called a thrust fault. When two plates collide, intense folding and faulting can occur. Examples of where reverse and thrust faults occur are where convergent boundaries are common such as: the Northern Rocky Mountains, the Alps, Himalayas, and the Appalachian mountains.
Image copyright: United States Geologic Survey, licensed as Creative Commons Public Domain.
3.3 Measuring Seismic Activity
Seismologists record seismic waves using a seismograph. When a rupture occurs within the earth, energy is released from the focus in all directions and the seismograph will record the magnitude of the energy. There are three types of seismic waves: P-waves, S-waves, and Surface waves.
Primary waves, also called P-waves, are compressional waves and are the first to be felt by seismographs and individuals because they travel the fastest (about 3.7 miles per second). To visualize a P-wave, think of stretching a slinky and letting it go. You would be able to actually see the compression occurring within the slinky.
The second type of seismic wave is called a secondary wave or S-wave. They reach the seismograph second because they travel slower than P-waves and travel in a side-to-side manner. Imaging pulling a slinky and shaking one end side to side. You would be able to see the side-to-side movement travel up the slinky. P-waves and S-waves together are called body waves because they travel through the earth rather than on the surface.
Surface waves are the last seismic waves to reach an area, create the greatest ground motion, and are the most destructive because they are the slowest and move in a rolling manner.
Image copyright: United States Geologic Survey, licensed as Creative Commons Public Domain.
3.4 Locating Seismic Activity
Image copyright: United States Geologic Survey, licensed as Creative Commons Public Domain.
In order to determine the location of an earthquake, seismologists must measure the interval distance of P-waves and S-waves released during the rupture. P-waves travel faster than S-waves, thus scientists calculate the time difference between both waves to determine a perimeter of the epicenter. But the epicenter could be anywhere within that perimeter. Therefore, scientists must use a minimum of three seismic readings from different seismograph stations in order to determine the exact location of the epicenter.
3.5 Classifying Earthquakes
Image copyright: Licensed as Creative Commons Public Domain.
There are two basic ways to measure the strength and destructive power of an earthquake. The first is called the Richter scale. Based on a range from 1 (weakest) to 10 (strongest), the Richter scale measures the magnitude (energy released) by an earthquake. The scale is logarithmic meaning that every whole number increase in magnitude is 10 times more ground shaking and 30 times more energy released. Example: a magnitude 7.0 earthquake has ground shaking 10 times more than a 6.0 and 30 times more energy released. A magnitude 8.0 earthquake has ground shaking 100 times more than a 6.0 and 900 times more energy released. The December 26, 2004 Indonesian earthquake had a magnitude of 9.1. It should be noted that for the strongest earthquakes, the Richter Scale is no longer used. Instead, the Moment Magnitude Scaleis used, though it is very similar to the Richter Scale. The Richter Scale and Moment Magnitude Scale provide quantitative information of the energy released from an earthquake.
The Modified Mercalli Intensity Scale (shown below) is more qualitative and focuses on the actual damage caused by the earthquake and its impact on human lives and property. The scale has 12 categories ranging from I (felt by very few people) to XII (total destruction). Each category is based on a description of how people felt or perceived the earthquake. The major problem with the Modified Mercalli Intensity Scale is that ground damage is relative to location. The scale can be influenced by the types of rocks underneath, if the ground is mostly bedrock, loose sediment, or even landfill, how well buildings are built, and how far away the people and buildings are from the epicenter. The farther away from the epicenter, the weaker the earthquake will feel. So the Modified Mercalli Intensity Scale is great to determine ground damage and how the earthquake affected people, but does not tell you how much energy was actually released from the rupture. Because of the access to the Internet, the United States Geologic Survey (USGS) allows you to email them if you just felt and earthquake. They take this information and create a map similar to the Modified Mercalli maps, but call it a shake map. To view real-time shake maps from the USGS, click here. For a list of recent earthquakes in Utah along with shake maps, check out the Seismology Departmentat the University of Utah.
Image copyright: United States Geologic Survey, licensed as Creative Commons Public Domain.
One final note, with the recent popularity of smart phones and the iTouch, there are several apps now available in relation to natural disasters. In terms of earthquakes, a highly popular app in Apple's iTunes is called QuakeWatch. There are probably similar apps for other smart phone devises.
3.6 Earthquake Hazards
Image copyright: United Nations Development Program, licensed as Creative Commons Public Domain.
Earthquakes do not kill people; falling buildings and highways kill people. History has taught us the importance of building codes to create safer buildings. Many of the massive death tolls reported by earthquakes are caused by poorly built buildings rather than the earthquake itself. In general, buildings or structures built out of brick, stone, mud, or reinforced concrete fair poorly in large earthquakes because there is very little flexibility in the structures as the ground shakes. The best types of buildings to be in are those built of wood because of there flexibility; the house may not be habitable after the earthquake, but they won't crumble or collapse on people. Buildings with weak floors or basement garages are also susceptible to collapsing.
There are several techniques engineers have developed to help buildings withstand the destructive power of earthquakes. Many buildings are being built or retrofitted with diagonal braces that can withstand the ground motions caused by an earthquake. Tall buildings also tend to sway at different frequencies them to slam into each other during an earthquake. If engineers know how much a building will sway, they can determine how far apart buildings must be built. Finally, engineers are placing rubber pads at the base of newly built and retrofitted buildings that act as shock absorbers.
Liquefaction can occur when earthquakes rupture in regions with loose sediment and high water tables. As the ground shakes, the high water table rises to the surface which softens and destabilizes the surface causing structures to break off their foundations or fall over. Liquefaction has occurred in Mexico City in 1985, San Francisco 1989, Anchorage, Alaska 1964, Kobe Japan in 1995 and will occur in Salt Lake City.
Image copyright: This work is in the public domain in that it was published in the United States between 1923 and 1977 and without a copyright notice.
Click here to see a map of liquefaction potential and ground shaking within Salt Lake County. (You can also look at maps for Tooele, Cache, Davis, Weber and Utah Counties.) For those who live in the Salt Lake valley, notice how the liquefaction potential is greatest along the Jordan River and near the Great Salt Lake. Any ideas why? It has to do with the fact the water table is highest near those areas. So when an earthquake occurs and the ground begins to shake, the water will rise and destabilize the ground. In these maps, the reds and purples represent the areas of greatest liquefaction potential from a magnitude 7.0 earthquake.
Earthquakes can also destabilize steep slopes causing them to slip and fail. These landslides tend to occur where the ground is mostly loose sandy soil with a high water table. Fires are also another serious hazard created by earthquakes as our infrastructure collapses and electrical and gas lines break. The treat of fires will also increase as emergency crews have a hard time maneuvering through the debris. There are two simple things individuals can do to reduce their risk of a fire: first is to have a wrench attached to their outside gas line. If you smell gas at your house, quickly turn off the gas. But if you do not smell gas, do not turn it off; doing so may prevent you from having heating in your house in the winter and it may be months before it gets turned back on. Second, make sure your water heater is attached to your house. A simple $20 bracket wrapped around your water heater and bolted into your house may prevent it from falling over and breaking its gas line.
Another interesting effect of powerful earthquakes is island creation. In September 2013, a moderately powerful earthquake off the coast of Pakistan created a 200 foot wide, 60 foot tall island. It won't last long because ocean waves will erode it back down, but it's an interesting and rare effect of earthquakes. Click here to learn more.
3.7 Human-Induced EarthquakesCan humans create earthquakes? Maybe not intentionally, but the answer is yes and here is why. If a water reservoir is built on top of an active fault line, the water may actually lubricate the fault and weaken the stress built up within it. This may either create a series of small earthquakes or potentially create a large earthquake. Also the shear weight of the reservoir's water can weaken the bedrock causing it to fracture. Then the obvious concern is if the dam fails. Earthquakes can also be generated if humans inject other fluids into a fault such as sewage or chemical waste. Finally, nuclear explosions can trigger earthquakes. In fact, one way to determine if a nation has tested a nuclear bomb is by monitoring the earthquakes and energy released by the explosion.
3.8 Earthquake PrepardenessEverywhere in the world has disasters, so nowhere is safe. But everyone should be prepared for the type of disasters their region experiences. Everyone should have a 72 hour kit prepared in your car and house. Recently the Federal Emergency Management Agency (FEMA) stated that citizens should prepare a 5-day kit in case federal, state, and local agencies can not reach you. Learn more how you can prepare at Ready.gov. Here are a few more items you should think about with disaster preparedness.
- Each member in your family should also know where to meet in case of a disaster.
- The number one reason why people end up in the hospital after an earthquake is glass in their feet. Having a pair of old shoes under your bed can greatly reduce that probability.
- Know how to shut off your gas line if you smell gas in your house. If it requires a wrench to shut off, always have one next to the line for quick shutoff. You will know if you have a gas leak because the gas companies place a chemical in the gas that will smell like rotten eggs.
- Also make sure your water heater is attached to your house. If your water heater falls over and the gas line breaks, your house can catch fire.
- If you and your family are safe, take care of others in need.
- Finally for those interested, look into getting CERT certified as a first responder.
This chapter was about Earthquakes.
The crust of the earth is a very thin layer and underneath that is the center which consists of hot melted rock, which is as hot as up to 3,500 degrees. The hot rocks are on the bottom and the cooler rocks are at the top which shoves into the earths crust. Once the rocks push against the earth they create plates, and the plates, they are constantly moving and rubbing against each other and fall under the other one, once the stress builds up the earth begins to shift and shake and an earthquake begins. 100,000 earthquakes happen every year with a total of 10,000 deaths and only one thousand earthquake a year are severe enough to actually feel.
I was surprised to learn that the Haiti earthquake left one of the highest death tolls. I never would have guessed that. Which chapter impacted you the most? All the death, and the lady in the beginning who talked about how her house fell on her baby. It’s so unreal to think about these kinds of things literally happening. It always makes me wonder how we here in Utah would react. If we would come together as these people in Haiti, or if it would be a one for himself free for all. Why? It’s just, it seems unrealistic to read about so many people dying all over the place in such a short amount of time and the lady whose baby died and was crushed by her house, just put the most horrifying visuals in my brain. It’s just so sad. these people who survived are such strong willed people. Cite at least 2 passages that seemed significant to you. The first one was, Getro Nelio who was 25. He watched his father die in front of him instead of going to save his dad, he decided to save 28 more people. Granted, his dad was going to die anyway, it must have took some real emotional strength, to just leave him there, knowing he was going to die anyway and to go save 28 more people. I guess, I would want that as well. If it were me dying as his dad was, if I was going to die anyway, or if not saving me, would save 28 more people. It just makes more sense that way.
The other story I really liked was, the story of how police and rescue disappeared seconds after the incident. That for many reasons like they were dead, or they could not reach their supplies of that, they just took off, that they were not around. So instead, the local survivors worked together and formed to help and assist people who were left for dead. I also thought that it was kind of a low blow for the rescue teams that did exist, that they immediately aided the rich and the foreigners. Granted, they are not from there, but the fact that they were staying at a fancy hotel and are from somewhere else or have more money, should not make the final decision on who gets to live or be helped first and who does not. Earth is constantly changing shape slowly, eventually the oceans will change and the continents will crash into each other, creating entirely new continents and new ocean areas, as well as new mountainous areas.
In terms of Human Rights, I feel like people should be allowed the right to be able to live in homes and be in businesses that have a safely built foundation and do not have to worry about the possibility of their baby getting crushed to death because a building fell on it. We are living in a time where people should have more of a possibility of living through natural disasters because of the technological advancements the world is constantly coming together with more opportunities for earthquake safe buildings and natural disaster safe environments. However, we need to come together as a world and take care of each other financially in terms of natural disaster safety, instead of being there to help with the damage after the fact.