Volcano lab google earth SVBR PDF

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Summary

First Lab of the year using google earth to find geographic locations...

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Dynamic Earth

Volcano Lab - Google EarthTm

Goal: To be able to describe and identify the common volcano types, and relate volcano types with associated volcanic hazards, tectonic setting, and geographic location.

Search Tool

Volcano shape is strongly controlled by eruptive style, which in turn is controlled by magma composition and tectonic setting. This lab is intended to give you the opportunity to examine volcanoes from around the globe, and to interpret the tectonic settings in which they form. To learn more about volcanoes, check out the following websites: the Smithsonian Institution Global Volcanism Program: http://volcano.si.edu/, Volcano World: http://volcano.oregonstate.edu/; USGS Volcanic Hazards Program http://volcanoes.usgs.gov/. What is Google Earth? GE (Google Earth) is a tool that provides topographic information as well as a 3D-view of the surface of the Earth. Using a Chrome Internet Browser, visit https://www.google.com/earth/ and click “launch Google Earth.” You may wish to go through the tutorial or you can skip it. Using the left tool bar, you can search for different locations with the “Search Tool” (example shown left).

My Places

We will import a map file (.kmz files) that will help us interpret the tectonic setting of different volcanoes around the world. I have given you this file in entitled plate-boundaries.kmz on Canvas. Download this file on a location such as your desktop. In the Google Earth browser, click on “My Places” on the left toolbar. Click on the settings and “Enable KML File Import” as shown below.

Measure Tool

Click the “Import KML File,” shown below and “open file”. Navigate to the folder (e.g. desktop folder) where your .kmz files are. Starting with the plate-boundaries.kmz file, import the file.

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You should see the different plates, similar to our Plate Tectonic Jigsaw. Notice that there are also the directions of plate motions.

Volcanoes! 1.

Navigate to Santiago Chile, in South America. The image should look like the screenshot below. You can zoom in and out with the “-” and “+” symbols and also turn on the 3D view. Play with these to see what happens.

Turn on 3D → Zoom in and out →→ 2

Notice how you can stop the location from moving my clicking on the screen and you can rotate the view and view angle by pressing shift + click and drag. Play with this to get a different view. Zoom out a bit until you can see the nearest plate boundary and plate direction. 2a. What type of plate boundary is found off the cost of South America between Santiago and Coquimbo? Remember the choices from our plate boundary type jigsaw assignment Oceanic Continental Convergent(subduct) 2b. What direction are the plates moving? Oceanic is moving NW into the continental plate.

2c. What are the names of the two plates associated with this area (HINT: you may want to load the TectonicPlateNames.kmz file located in Canvas to help you identify each plate)? _ Nazca & South America 2d. How fast do you think this plate moves (Make a hypothesis and answer in inches/year)?__ I

← Top → Width →→

← Base →

belive the plate to move at .8 inches / year 2e. What major landforms run north-south approximately 150 miles east of the plate boundary near Santiago? Mountains 2.

Now navigate to Descabeza (search for the following lat/long coordinates to get there: -35.58, -70.75). Zoom out far enough that you can tell where in the world you are, to orient yourself. You should be in the same tectonic setting (on the same plate) as Santiago. Zoom back in to get a good view of the shape of the volcano.

Notice additional information in the lower-right part of the screen (circled above). Notice as you move the cursor around the landscape, the lat/long coordinates and the elevation (given in meters (m)) change. We will be using the elevation value and the measure tool to calculate slope of different volcanoes. The shape of different volcanoes is indicative of the composition, viscosity, and ultimately behavior and hazards associated with the volcano. These characteristics vary by tectonic setting. a)

Describe the size and shape of the volcano by filling in the spaces, below: (I have marked with stars approximately where I would hover the cursor for the top and base of the volcano) 3

Maximum height (elevation) of the volcano above sea level: 3913 meters. Base elevation of the volcano: 2484 meters. Relief (maximum elevation – base elevation): 1429 meters total height. Use the measure tool to measure the total width of the volcano in meters. (I have indicated in the image on last page where I would measure). Base width: __3693.37__ meters. Now you will calculate the slope of the volcano. Remember, slope is rise over run. You have now measured the elevation of the top of the volcano, the elevation of the base of the volcano, and the total width, as shown below. Top Elevation (m)

Bottom Elevation (m) Width (m)

Relief

Width (m) The relief is the height of the volcano. Remember that slope is rise over run of a right triangle (triangle with a 90 degree or perfect corner). We have the rise (relief) and we need the run (horizontal distance of the triangle). If we redraw half of the triangle (half of the volcano), we can see that we do indeed have a right triangle. With the relief the vertical rise, and ½ the width the horizontal distance, or run.

Relief

½ Width (m)

Slope is equal to rise over run. Therefore, slope of the volcano is equal to relief divided by half of the width. Calculate the slope of the volcano by dividing the relief you calculated above by ½ the width. To make the calculation easier, you may wish to divide the width by two separately. ½ width: 1,846.685 m

Now, take the relief and divide it by the ½ width you just calculated to calculate slope: 0.773819 This number is a decimal (no units), and to make it easier to read, we usually multiple this by 100 to get a percent (%) slope. Multiply your slope by 100 77.3819% 4

This is your slope calculation! For the remainder of the assignment, I will simply ask for the following (below), but you may wish to break the calculation down into the steps you just did for all the volcanoes if you struggle to do all the steps at once. Average slope of volcano (relief ÷ ½width)*100)=77.3% (slope in percent) b)

Sketch and describe the overall shape of Descabeza. You can do this on paper and scan or take a picture of it, or you can use a program such as Paint or insert shapes by clicking “Insert” and “Shapes” in the toolbar at the top of Word. Try to capture the essence of the volcano and label the most important features. Is it steep? Does it have a crater? What’s the color?

Very steep, Has a crater,however, it Appears to have a top to the crater. Very bumpy land around the Volcanoe As well

c)

Describe the likely composition (mafic, intermediate, felsic) of this volcano, based on your observations. Explain your answer. Felsic if my hypothesis of this being a strato Volcanoe is correct.

d)

Describe the major geologic hazards (e.g. eruptions, volatile eruptions, tsunamis, earthquakes, etc.) associated with this volcano. High viscosity Magma, Eruption possible, cools and hardens before spreading

e) Zoom out and examine the region. Describe the likely tectonic setting of the volcanoes of the Andes mountains (crust types and relative motion). Hint: is there a deep ocean trench to the west of the mountains? Convergent Oceanic / Continental Boundary f)

Referring to the lecture notes on volcanoes in addition to your book, hypothesize about the volcano type, based on size, shape, and composition. Due to large slope and what looks to be a crater in the middle, makes me believe this volcano to be a strato volcano.

4. Navigate to Mt. St. Helens (46.1958, - 122.1821) in southern Washington, USA. a)

Maximum height (elevation) of the volcano above sea level: 2530_ meters. Base elevation of the volcano: 1416_ meters. Relief (maximum – base elevation) = _1,114__meters total height. Base width: _5,709Meters. Average slope of volcano ((relief ÷ ½width)*100%):___39.03%__

b)

Sketch and describe the overall shape of Mt. St. Helens:

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c)

Describe the likely composition of this volcano, based on your observations. Explain your answer.

Mafic (more silicate)

d) Describe the major geologic hazards associated with this volcano. -Very Eruptive - Low viscous Magma e) Zoom out and examine the region. Are there any other volcanoes nearby? Describe the likely tectonic setting of the volcanoes of the Cascade Range. Support your answer with observations on the major tectonic landforms of the region. No other Volcanoes. It is actually very green and “hilly” around as the hills are not large enough to be considered mountains I think?

f) Referring to the lecture notes on volcanoes in addition to your book, hypothesize about the volcano type, based on size, shape, and composition, hypothesize about the volcano type, based on size, shape, and composition. Definite Strato-Volcano 5. Navigate to Mauna Loa on the BIG island of Hawaii (central Pacific Ocean) (19.4715, -155.59039). a) Maximum height (elevation) of the volcano: __4120_ meters above sea level. Base elevation of the volcano: 3030 meters above sea level. Relief (maximum – base elevation) = _1,090_meters, total height. Base width: 10,230 meters. Average slope of volcano ((relief ÷ ½width)*100%):__21.3%___ b) Sketch and describe the overall shape of Mauna Loa.

Not Steep (Looks almost Like diverging Plates)

c) Describe the likely composition of this volcano, based on your observations. Explain your answer.

Mafic due to non explosive nature of the magma

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d) Describe the major geologic hazards associated with this volcano. -Not many, no explosive eruptions and a very shallow slope

e) Zoom out and examine the region. Describe the likely tectonic setting of the Hawaiian Islands. (Hint: think back to your tectonic homework). Support your answer with observations on the major tectonic landforms of the region. Very flat Ocean continental convergent

f) Based on the lecture notes on volcanoes and your referring to your book, hypothesize about the volcano type, based on size, shape, and composition. Shield Volcano

6. Navigate to Mt. Fujiyama, Japan (35.364, 138.731). a) Maximum height (elevation) of the volcano above sealevel :____3730 meters. Base elevation of the volcano: ___1480 meters. Relief (maximum – base elevation) = 2,250_meters total height. Base width: ___8935 meters. Average slope of volcano ((relief ÷½width)*100%) = 50.36%________

b) Sketch and describe the overall shape of Mt. Fujiyama: Very Steep with flat surroundings

c) Describe the likely composition of this volcano, based on your observations. Explain your answer.

With this volcano being mainly basaltic, I hypothesize its composition being Mafic

d) Describe the major geologic hazards associated with this volcano.

Inactive for 300+ years but if/ when eruption occurs, it will be very violent.

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e)

Zoom out and examine the region. Describe the likely tectonic setting of the volcanoes in Japanese region. Support your answer with observations on the major tectonic landforms of the region. Surrounded by Continental/ Continental Convergent boundaries

f)

Referring to the volcano lecture notes and your book, hypothesize about the volcano type, based on size, shape, and composition. Strato-Volcano

7. Navigate to Mt. Alayta, Ethiopia (12.887, 40.573). a) Maximum height (elevation) of the volcano above sea evel :_1,500 meters. Base elevation of the volcano: 1,380_ meters. Relief (maximum – base elevation) = __120 meters total height. Base width: _560 meters. Average slope of volcano ((relief ÷ ½width)*100):52%(Crater slope)_________ b) Sketch and describe the overall shape of Mt. Alayta:

c) Describe the likely composition of this volcano, based on your observations. Explain your answer.

I believe it is mafic because of the fact it being a shield volcano

d) Describe the major geologic hazards associated with this volcano.

Not many, a very mellow inactive volcano

e)

Zoom out and examine the region. Describe the likely tectonic setting of the volcanoes in the region (crust type and motion). Support your answer with observations on the major tectonic landforms of the region.

Very flat around volcanoe showing a small rise in elevation towards top of volcano

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f)

Based on the lecture notes about volcanoes and referring to your book, hypothesize about the volcano type, based on size, shape, and composition. Shield Volcano

Shield Volcano

8. Navigate to Aniakchack, Alaska (56.901, -158.142). a) Maximum height (elevation) of the volcano above sea level :_934 meters. Base elevation of the volcano: 634 meters. Relief (maximum – base elevation) = 300 meters total height. Base width: 2024 meters. Average slope of volcano ((relief ÷ ½width)*100): 29.64% b) Sketch and describe the overall shape of Aniakchack:

c) Describe the likely composition of this volcano, based on your observations. Explain your answer.

I belive it to be felcis. Calderas were once strato’s and the felsic (high viscous magma) creates the crater Then forming a caldera volcano

d) Describe the major geologic hazards associated with this volcano. Very dangerous. Calderas are the most powerful volcanoes. -Ash -Rock Fragments

e) Zoom out and examine the region. Describe the likely tectonic setting of the volcanoes in the region (crust type and motion). Support your answer with observations on the major tectonic landforms of the region.

Volcano is surrounded inside of another crater(most likely formed from the magma as it was a previous strato.

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f) Based on the volcano lecture notes and referring to your book, hypothesize about the volcano type, based on size, shape, and composition. Caldera

9. Plot your measured values for the volcanoes examined in this lab, on the graphs below. You can do this by moving the dots I made to the appropriate place. Don’t worry about being exact, just get it in the right ball park. Recall that your measurements are in meters (m), and the plot below is in kilometers (km). There are 1 meters in 1 km. If you measured 6000 meters for the width, this will be equal to 6 km on this plot. To convert from m to km, divide your width measurement by 1000.

Width (km) 200 180 160 140 120 100 80 60 40 20 0 Repeat for Releif. This one you can stick with meters.

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Relief (m) 5000 4500 4000 3500 3000 2500 2000 1500 1000 500 0

Repeat the same process for slope

Slope (%) 70 60 50 40 30 20 10 0

And finally for composition

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Composition Mafic

Intermediate

Felsic

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Summarize volcano type/composition relationships. Go back to your answer for question ‘f’ for each volcano examined in lab, and make sure you have a good answer! Then use your observations and interpretations to complete the following statements and questions. Use Tables 1-3, on the next page, for appropriate terms.



Shield volcanoes usually have a wide dome shape, low slope, and a mafic composition. The most common hazard(s) are: Possible sudden and violent reaction of gas and debris

Shield volcanoes commonly form in these tectonic settings: Form along divergent plate boundaries Explain your answer (relate volcano type to magma composition – where does the magma come from?)



Composite volcanoes usually have a Steep Cone shape, Steep slope, and a felsic composition. The most common hazard(s) are:

explosive volcanism: pyroclastic flows, ejecta, lahars, ash fall The most common tectonic setting of composite volcanoes is at: convergent boundaries. Explain your answer (relate volcano type to magma composition – where does the magma come from?)



Caldera volcanoes usually have an open crater with raised rim shape, moderate slope, and a intermediate- felsic composition. The most common hazard(s) are: -Violent explosion -rock shards -ash’s -gas’s

Caldera volcanoes commonly form in these tectonic settings:

Intracontinental extension 13

Explain your answer (relate volcano type to magma composition – where does the magma come from?)

Table 1 Shapes Wide dome Steep cone Open crater with raised rim Table 2 Slopes Low (0 – 10 %) Moderate (11 – 20%) Steep (>20%) Table 3 Composition Mafic Intermediate - Felsic Felsic

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