# 9.9: Lab Exercise (Part D)

## Part D - Volcanic Landforms

The composition of magma or lava may also control what type of volcanic features or landforms are seen on the earth’s surface. In this exercise, you will use Google Earth to identify these landforms. Figures 9.9 through 9.11 may help you in this section. For the Google Earth questions, copy and paste the latitude and longitude coordinates into the search bar (or just type them in).

13. Type 43 25 04.18N 113 31 37.38 W in the search bar of Google Earth. Zoom out to an eye elevation of ~90 miles. Based on the size of the area which is dark-colored and sparsely vegetated, this region is:

a. a basaltic dike

b. a shield volcano

c. a lava dome

d. a flood basalt

14. Click on the nearby photo icon (SW of your latitude/longitude coordinate in Question 13) to view a picture of the area as seen from the ground. This is a picture of:

a. a basalt flow

b. a felsic dome

c. a plutonic rock

d. an ultramafic rock

15. How many miles in length is this dark-colored feature? (measure the greatest length)

a. ~8 miles

b. ~20 miles

c. ~40 miles

d. ~50 miles

16. Type 46 12 07.84N 121 31 02.85W in the search bar of Google Earth. This volcano (Mt. Adams) has a lot of snow cover and small glaciers on it, but you can still see the volcanic rock, especially on the eastern flank (side) of the volcano. Zoom in to an eye altitude of ~9000ft to closely examine the rocks on this eastern side of the volcano; do you see any evidence of layering? This volcano is:

a. a shield volcano

b. a lava dome

c. a composite volcano

d. a large volcanic dike

17. How tall is Mt. Adams, and what is the length of its base (in the widest, N-S dimension)? You will need to zoom out to an eye altitude of ~17 miles to measure the base.

a. ~12,290 ft above sea level, and over 7 miles long

b. ~11, 890 ft above sea level, and over 4 miles long

c. at least 12, 703 ft above sea level, and over 6 miles long

d. unable to determine because of the ice

18. Compared to the Big Island of Hawaii (19 53 48.36 N 155 34 58.11 W, or refer to Figure 9.6), which is actually the volcano Mauna Loa, Mt. Adams is:

a. the same height, but the base is a lot smaller

b. the same height, but the base is a lot wider

c. smaller in height, and smaller at the base

d. smaller in height, but larger at the base

19. Type in 58 15 58.56 N 155 09 35.98 W in the search bar of Google Earth. Examine the shape of this feature by zooming in to an eye altitude of ~3330 ft; use the eye icon in the upper right corner to rotate the view. Now zoom out to an eye altitude of ~7306 ft to see the entire structure and the surrounding area. Based on the size and appearance of this volcanic feature, this is a:

a. dike

b. shield volcano

c. lava dome

d. flood basalt