Assignment #5 Module 9

is not

The change in velocity of the S waves in zone 'B' indicates that it __________ similar to zone 'A'. - is - is not

b. 100 kilometers

The top of the asthenosphere in Figure 8.12 occurs at a depth of approximately __________ . a. 300 kilometers b. 100 kilometers c. 500 kilometers d. 600 kilometers

c. Continental crust has the average composition close to that of an ingenious rock called granite

The two parts of Earth's crust are continental crust and oceanic crust. Which of the following statements is correct? a. Continental crust and oceanic crust have the same thickness b. Oceanic crust is primarily composed of an - ingenious rock called granite c. Continental crust has the average composition close to that of an ingenious rock called granite d. Continental crust is thinner than oceanic crust e. Continental crust has the average composition close to that of an igneous rock called basalt

decreases

The velocity of P and S waves __________ immediately below zone 'A' in the upper part of zone 'B'. - increases - decreases

b. decreases

The velocity of P waves __________ as they enter zone 'D'. a. increases b. decreases

increases

The velocity of both P and S waves __________ with increasing depth in zone 'A'. increases decreases

d. has not / solid

Using the curves plotted in Figure 8.11, the melting curve for basalt indicates that the lithosphere above approximately 100 km __________ reached the melting temperature of basalt and therefore should be __________ . a. has / molten b. has not / molten c. has / solid d. has not / solid

a. 1400 /14

Using the data in Table 8.2 and graph in Figure 8.11, the average temperature gradient for the upper 100 km of Earth is __________ degrees Celsius/100 km and __________ degrees Celsius/km. a. 1400 / 14 b. 2800 / 28 c. 700 / 7 d. 2100 / 21

b. 20 - 25 km

Using the graphs constructed in Figure 8.11 from Table 8.2 and Table 8.3, at approximately what depth within the Earth would wet granite reach its melting temperature to form granitic magma? a. 5 - 10 km b. 20 - 25 km c. 50 - 55 km d. 100 105 km

d. S waves slow down but still pass through this zone indicating that it is partly molten and therefore capable of flow

Why do scientists believe that the zone between 100 km and 700 km depth is capable of "flowing"? a. S waves speed up when passing through this zone so it must be flowing b. This zone is of lower temperature than rocks above it so it must not be very rigid c. This zone does not allow S waves to pass through and therefore must be flowing d. S waves slow down but still pass through this zone indicating that it is partly molten and therefore capable of flow

b. changes

With regard to the temperature curve you drew in Figure 8.11, the rate of increase of Earth's internal temperature __________ with increasing depth. a. changes b. is constant

b. greater

With regard to the temperature curve you drew in Figure 8.11, the rate of temperature increase from the surface to 100 km depth is __________ than the rate of increase below 100. a. less b. greater

a. 1400

With regard to the temperature curve you drew in Figure 8.11, the temperature at the base of the lithosphere, which is about 100 kilometers below the surface, is approximately __________ degrees Celsius. a. 1400 b. 1800 c. 600

600 kilometers

At approximately what depth do the deepest earthquakes occur in the area represented on Figure 8.12? a. 800 kilometers b. 100 kilometers c. 600 kilometers d. 400 kilometers

E. Mantle D. Inner Core B. Lithosphere A. Outer core C. Asthenosphere

For Figure 8.10, match each of the following zones in Earth's interior with the appropriate letter ID as indicated in the figure. ____ Mantle ____ Inner Core ____ Lithosphere ____ Outer core ____ Asthenosphere A. Zone 'D' B. Zone 'A' C. Zone 'B' D. Zone 'E' E. Zone 'C'

8 km/s and 4 km/s

For zone 'A', what are the approximate velocities of P and S waves in that order? 12 km/s and 16 km/s 8 km/s and 4 km/s 4 km/s and 12 km/s 16 km/s and 12 km/s

b. Asthenosphere

Referring to Figure 8.10, what is the name of the zone within Earth that begins at a depth of about 100 km and may extend to approximately 700 km? a. Lithosphere b. Asthenosphere c. Lower mantle d. Core

b. The earthquake pattern traces the outline of a descending slab

Regarding Figure 8.12, why have Earth scientists been drawn to the conclusion of a descending slab of solid lithosphere being consumed into the mantle near Tonga? a. Earthquakes are only associated with descending slabs and do not occur in any other tectonic environment b. The earthquake pattern traces the outline of a descending slab c. Surface volcanoes in the figure prove that a slab is sinking into the mantle since volcanoes are only associated with subduction zones d. The asthenosphere is only present in areas of subducting slabs and is not found anywhere else on Earth.

a. 100 km / Partly melted

The curves plotted in Figure 8.11 indicate that basalt reaches its melting temperature within Earth at a depth of approximately __________ km. __________ basaltic material would be expected to occur below this depth. a. 100 km / Partly melted b. 50 km / Solid c. 100 km / Solid d. 50 km / Partly melted

b. nearly along a line

The earthquake foci in the area represented in Figure 8.12 are distributed __________ . a. in a random manner b. nearly along a line

100 kilometers

The layer labeled 'A' on Figure 8.10 is the solid, rigid, upper zone of Earth that extends from the surface to a depth of about __________ . 500 kilometers 1,000 kilometers 100 kilometers

c. P wave velocity increases at the top of zone 'E' indicating that Zone 'E' is solid

What change in velocity do P waves exhibit at the top of zone 'E' and what does this suggest about the zone? a. P wave velocity decreases at the top of zone 'E' indicating that Zone 'E' is liquid b. P wave velocity increases at the top of zone 'E' indicating that Zone 'E' is liquid c. P wave velocity increases at the top of zone 'E' indicating that Zone 'E' is solid d. P waves stop at the top of zone 'E', so we can't determine anything about this zone

S-waves pass through zone 'C'

What fact concerning S waves indicates that zone 'C' is not liquid? - S-waves do not pass through zone 'C' - S-waves pass through zone 'C' - S-waves in zone 'C' are traveling faster than P-waves - S-waves slow down at increasing depths within zone 'C'

d. S waves do not pass through zone 'D', indicating that it is liquid

What happens to S waves when they reach zone 'D' and what does this indicate about the zone? a. S waves speed up when passing through zone 'D', indicating that it is liquid b. S waves do not pass through zone 'D', indicating that it is composed of a very dense solid c. S waves do not pass through zone 'D', indicating that it is composed of a porous solid d. S waves do not pass through zone 'D', indicating that it is liquid

a. Iron

What is the probable composition of the core? a. Iron b. Oxygen c. Silica d. Magnesium

b. Ultramafic magnesium-rich silicate rock

What is the probable composition of zone 'C'? a. Iron and nickel b. Ultramafic magnesium-rich silicate rock c. Felsic igneous rock like granite d. Mafic igneous rock like basalt

lithosphere

Zone 'A' in Figure 8.10 is called the __________ . core mantle lithosphere

asthenosphere

Zone 'B' is called the __________ . - crust - asthenosphere - core

660 kilometers

Zone 'B' is the part of Earth's mantle that extends from the base of zone 'A' to a depth of about __________ in some regions of Earth. 180 kilometers 660 kilometers 2,250 kilometers

2900 kilometers

Zone 'C' (which includes the lower part of zone 'A' and zone 'B') extends to a depth of __________ . - 2900 kilometers - 600 kilometers - 6400 kilometers - 5100 kilometers

mantle

Zone 'C' is called Earth's __________ . - asthenosphere - outer core - mantle - inner core

a. 5100

Zone 'D' extends from ~2900 km to about __________ kilometers depth. a. 5100 b. 6100

a. outer core

Zone 'D' is Earth's __________ . a. outer core b. mantle c. lithosphere d. inner core

d. 5100 / center

Zone 'E' extends from a depth of __________ km to the __________ of the Earth. a. 6400 / center b. 2900 / surface c. 5100 / surface d. 5100 / center

d. inner core

Zone 'E' is Earth's __________ . a. mantle b. asthenosphere c. outer core d. inner core