Question
HW#5 Interpreting Plate Tectonics from Topography and Rock Samples
Applying your knowledge of boundaries to identify plate boundaries of two unknown continents.
In this homework we are going to apply what we are discussing in class about the characteristics of plate
boundaries (e.g. topography, earthquakes, tectonic activity, etc), the processes at these plate
boundaries, and the rocks that will be found there, to interpret the plate boundaries of two unknown
continents.
You will be asked to complete the following
1. Identifying topographical features on a shaded relief box diagram
PDF version of that single image available in D2L from the quiz page : HW#5 Shaded Relief Image with
Locations
2. Identify characteristics rocks samples from each location (rock type and rock name) which will clue
you in to the types of processes that are dominate at that location
3. Identify the type of plate boundary at each location
4. Predict the likelihood and distribution of earthquake and volcanic activity, based on your previous
interpretation.
This homework is intended to be a review for the upcoming exam, so recommend make sure that you
have your versions of the rock cycle, Bowen’s Reaction series, and the various concept maps we have
been completing as you work on the homework. Also recommend reviewing previous homework and
mastery quizzes as well.
Pre Homework Questions ( 1 pt)
Below are statements that reflect some of what you should be getting out of this assignment
Before you complete the assignment, rate how true each of the following statements is for you using a
scale of 1-­‐
s for these pre-­‐
questions are graded only for being complete (1 pt all or nothing) and not what your answers are.
1. I am comfortable identifying if a rock is igneous, sedimentary, or metamorphic
based on appearance and description.
2. I can identify igneous rocks based on mineralogy and texture.
3. I can identify metamorphic rocks based on mineralogy and texture.
4. I can identify sedimentary rocks based on texture and sedimentary features.
5. Based on the rock type (e.g. sedimentary, igneous, or metamorphic) and its
appearance, I can infer the conditions under how that rock formed and associate
that with a potential plate boundary
6. I am comfortable associating the topographic features and tectonic activities for
each of different plate boundaries

Identifying topographic features and rock samples
Use the image provided in the pdf linked to the homework or here and the follow rock picture and
descriptions to answer the following identification questions.

7. Which of the location(s) present on the diagram has mountains above sea level? Select all that
apply

o Location 1
o Location 2
o Location 3
o Location 4
o Location 5

8. Which of the location(s) present on the diagram has large ridges below sea level? Select all that
apply
o Location 1
o Location 2
o Location 3
o Location 4
o Location 5

9. Which of the location(s) present on the diagram has a thick amounts of clastic sediments resulting
in a wide continental shelf? Select all that apply
o Location 1
o Location 2
o Location 3
o Location 4
o Location 5

10. Which of the location(s) present on the diagram has a deep ocean trench? Select all that apply

o Location 1
o Location 2
o Location 3
o Location 4
o Location 5

11. Which of the location(s) present on the diagram is relatively flat with a thin layer of sediment over
basalt? Select all that apply
o Location 1
o Location 2
o Location 3
o Location 4
o Location 5

Location 1 samples

Down below are two samples of rocks collected from Location 1. Use the image and the descriptions to
identify the rock type (e.g. sedimentary, igneous, or metamorphic) and also the specific rock name (e.g.
granite, gneiss, basalt, sandstone, etc…).
Location 1: Sample 1
This rock sample is crystalline with characteristics
bands of a light and dark colored minerals. The light
colored minerals bands appear to be dominated by
a hard white to translucent mineral that fractures.
The dark mineral bands are dominated by a dark,
vitreous mineral with non-­‐perpendicular cleavage.

12. Based on the image and the description provided what rock type is sample 1? Choose one

o Sedimentary
o Igneous
o Metamorphic

13. Based on the image and description was is the specific rock name for sample 1?

Location 1: Sample 2
This rock sample is crystalline as well, but the
individual crystals are hard to see even with the use
of a hand lens. The image provided is close up and
the minerals are still hard to see. Analysis does not
find much quartz. Instead common minerals are
dark silicate with non-­‐perpendicular cleavage and a
white, hard mineral that is rich in sodium (Na).

14. Based on the image and the description provided what rock type is sample 2? Choose one

o Sedimentary
o Igneous
o Metamorphic

15. Based on the image and description was is the specific rock name for sample 1?

Location 3 samples

Down below are two samples that were collected from location 3. Use the images and descriptions to
identify if what rock type they are and the specific rock name.

Location 3, Sample 3
It was necessary to dig deep into the crust at
location 3 to get this sample. It is crystalline with
visible crystals of dark colored minerals. These
minerals are mainly black in color, but one of them
appears to have a bluish look to it.

16. Based on the image and the description provided what rock type is sample 3? Choose one

o Sedimentary
o Igneous
o Metamorphic

17. Based on the image and description was is the specific rock name for sample 3?

Location 3, sample 4
This sample was collect on the surface at
this location. It is finely crystalline with
very dark minerals

18. Based on the image and the description provided what rock type is sample 4? Choose one

o Sedimentary
o Igneous
o Metamorphic

19. Based on the image and description was is the specific rock name for sample 4?

Location 4 samples

Down below are two samples of rocks collected from Location 4. Use the image and the descriptions to
identify the rock type (e.g sedimentary, igneous, or metamorphic) and also the specific rock name (e.g.
granite, gneiss, basalt, sandstone, etc…).
Location 4 sample 5.
This dark rock has very thin layers, breaks apart
easily, and has deep sea fossils. The clasts are so
fine they cannot be seen, even with a hand lens.

20. Based on the image and the description provided what rock type is sample 5? Choose one

o Sedimentary
o Igneous
o Metamorphic

21. Based on the image and description was is the specific rock name for sample 4?

Location 4 sample 6.
This sample was taken from underneath the layer
that sample 5 was taken from. It is also dark in color,
but crystalline and no evidence of fossils. The crystals
are so fine that it is hard to see them, even with a
hand lens.

22. Based on the image and the description provided what rock type is sample 6? Choose one

o Sedimentary
o Igneous
o Metamorphic

23. Based on the image and description was is the specific rock name for sample 6?

Location 5 samples

Down below are two samples of rocks collected from Location 4. Use the image and the descriptions to
identify the rock type (e.g sedimentary, igneous, or metamorphic) and also the specific rock name (e.g.
granite, gneiss, basalt, sandstone, etc…).

Location 5 sample 7.
This rock has visible sand size grains, which are
dominated by one type of mineral. The mineral is
white to translucent in color, hard, and does not
cleave. Bi-­‐directional cross beds are present as well
as clam fossils.

24. Based on the image and the description provided what rock type is sample 7? Choose one

o Sedimentary
o Igneous
o Metamorphic

25. Based on the image and description was is the specific rock name for sample 7?

Location 5 sample 8.
This sample has smaller grains than sample 7. They
are fine and hard to see, but you can feel them
when you run your hands over the sample. The
sample has a little gritty feel to it. There can be very
fine bi-­‐directional cross beds present, but more
often see ripples and marine animal burrows.

26. Based on the image and the description provided what rock type is sample 7? Choose one

o Sedimentary
o Igneous
o Metamorphic

27. Based on the image and description was is the specific rock name for sample 7?

Identifying and Interpreting Plate Boundaries

Use the topographical features that you identified on the box diagram of the two continents and the
identification of the rock samples that infer geologic processes at each location to identify and interpret
the different plate boundaries present.
Question 28 (4 points)

28. Down below is a list of specific types of plate boundaries that are possible. For each location on
the diagram select the term that best described the plate boundary (nor not a plate boundary).
Note: Each answer can be used more than once or not at all.

1. Oceanic Divergent Plate Boundary

2. Continental Divergent Plate boundary
__ Location 1
3. Not a plate boundary, but a passive margin
__ Location 2
4. Not a plate boundary, but an abyssal plain.
__ Location 3
5. Ocean to ocean convergent plate boundary with
subduction
__ Location 4
6. Ocean to continent convergent plate boundary
with subduction
__ Location 5
7. Continent to continent convergent with collision

8. Transform plate boundary

29. In one to two complete sentences describe which direction continent B is moving relative to
continent A and explain your answer. Assume the rate of plate movement is the same for all
boundaries. (2 pts not in a complete sentence, no points are given)

Locations of tectonic activity and potential hazards.

Based on your interpretation of type of plate boundary present (or not) for each location, identify which
locations will be most likely to have the various types of earthquake and volcanic activity.
30. Which of the following locations would you expect to find the hypocenter of deep earthquakes
(depth greater than 300 km, so into the mantle)? Select all that apply

o Location 1
o Location 2
o Location 3
o Location 4
o Location 5

31. Which of the following locations would you expect to have shallow earthquakes (less than 20 km
depth) on the topographical feature that indicates the plate boundary? Select all of the locations
that apply.

o Location 1
o Location 2
o Location 3
o Location 4
o Location 5

32. Which of the following locations would earthquakes be an uncommon event? Select all that apply

o Location 1
o Location 2
o Location 3
o Location 4
o Location 5

33. Which of the following locations would volcanoes or fissures with mafic magmas be a common
event? Select all that apply
o Location 1
o Location 2
o Location 3
o Location 4
o Location 5

34. Which of the following locations would volcanoes with intermediate or felsic magmas be a
common event? Select all that apply

o Location 1
o Location 2
o Location 3
o Location 4
o Location 5

35. Which of the following locations would volcanic activity (volcanoes or fissures) be an uncommon
event? Select all that apply

o Location 1
o Location 2
o Location 3
o Location 4
o Location 5

36. You are in charge of locating a nuclear power plant in a geologically sound area with a extremely
low chance of volcanoes and strong earthquakes. Using your knowledge of plate boundaries and
associated volcanic and earthquake activity and your answers for the questions above to decide on
which continent on the provided image would you place the nuclear plant. In one to two complete
sentences identify the continent and explain why? (2 pts) . Points will only be awarded for
responses that are in one to two complete sentences.

Post Homework Questions ( 2 pt)
Below are statements that reflect some of what you should be getting out of this assignment
Before you complete the assignment, rate how true each of the following statements is for you using a
scale of 1-­‐
s for these pre-­‐
questions are graded only for being complete (1 pt all or nothing) and not what your answers are.
37. I am comfortable identifying if a rock is igneous, sedimentary, or metamorphic

based on appearance and description.
38. I can identify igneous rocks based on mineralogy and texture.

39. I can identify metamorphic rocks based on mineralogy and texture.

40. I can identify sedimentary rocks based on texture and sedimentary features.

41. Based on the rock type (e.g. sedimentary, igneous, or metamorphic) and its

appearance, I can infer the conditions under how that rock formed and associate
that with a potential plate boundary
42. I am comfortable associating the topographic features and tectonic activities for
each of different plate boundaries

43. In the space down below, write a sentence on what skills or knowledge you are feeling more
confident on now after completing this exercise OR what questions you may still have after
completing this exercise.