Geology Chapters 1/2 Uark

31. In the mid-20th century, researchers dredging the seafloor could not find any materials older than

180 million years

34. A typical rate of seafloor spreading in the Atlantic Ocean is (blank)

2 cm per year

8. What is the accepted age of the Earth?

4.6 billion

39. How are normal polarity and reverse polarity of Earth's magnetic field different?

A compass points toward the North Pole during normal polarity ant to the South Pole during reverse polarity

39. In general, what is our best evidence that the orientation of Earth's magnetic field has changed over time?

A record of Earth's magnetic field is recorded in oceanic rocks, which show a clear pattern of changes in Earth's magnetic polarity

4. Which of the following statements about the rock cycle is correct?

A sedimentary rock subjected to intense heat and pressure will become a metamorphic rock.

11. Components of the Earth system that created and were affected by this natural disaster(mudslide) to demonstrate the interconnectivity of Earth system. Geosphere Hydrosphere Biosphere Atmosphere

ALL

32. Which of the following is a layer of the Earth that is classified NOT by composition, but by physical properties?

Asthenosphere

1. The doctrine of ______ held that the major features of the surface of the earth were created by sudden, short-lived, violent events.

Catastrophism

30. Which of the following statements best describes Wegener's idea of continental drift?

Continents were formerly in different positions on the Earth and have shifted to their present locations over time.

40. What generates the heat necessary for convection in the Earth?

Decay of radioactive materials

39. Which of the following statements about Earth's magnetic field is most accurate?

Earth's magnetic field switches polarity at irregular time intervals

15. T/F hypotheseis can ever be changed or motifed

False

30. How was the fossil record of ancient life used to support Wegener's hypothesis about Pangaea?

Fossils of identical organisms were found on several continents, indicating the continents were once joined.

32. How is the thickness of the lithosphere going to change as it moves away from a divergent plate boundary?

Lithosphere will thicken as more mantle is added

25. (Blank) is an example of a transform plate boundary.

The San Andreas Fault

19. If the temperature in the Earth generally increases with depth, how is it possible that the Inner Core is a solid?

The pressures in the core are immense and keep it in a solid state in spite of the temperature

20. Which statement about the theory of plate tectonics is correct?

The rigid lithosphere plates overlay the hotter and weaker asthenosphere

26. Which of the following pieces of evidence supports the plate tectonic theory?

The stripe patterns of high- and low- intensity magnetism are the same on both sides of an oceanic ridge.

33. Why are volcanoes NOT found at transform boundaries?

Transform boundaries do not cause changes to the pressure, temperature, or composition of the mantle

9. The Principle of ________ states that the physical, chemical, and biological processes at work shaping the Earth today have also operated in the geologic past.

Uniformitarianism

35. Why are the mid-ocean ridges higher in elevation than the surrounding ocean floor?

Warmer material near the ridge is less dense, so floats higher on the mantle.

21. Which feature of Wegener's idea of continental drift contributed to its rejection by the scientific community?

Wegener proposed that gravitational forces from the Sun and Moon could move continents.

23. (Blank) is a feature of a divergent plate boundary.

an oceanic ridge, a rift valley

3. The air we breathe is part of the __________.

atmosphere

28. Australia is composed of relatively old and thick

continental crust

33. In general, where do earthquakes and volcanic eruptions occur?

convergent plate boundaries and divergent plate boundaries

39. Which type of plate boundary is most closely associated with the formation of new ocean floor?

divergent

39. How often does the Earth's magnetic field switch polarity?

every 100,000 to several million years

28. Layered (blank)

exposed by erosion can be seen when looking at the Grand Canyon in the United States

10. T/F? The four spheres on Earth operate independently from each other.

false

28. The earthquakes that occur in Southern California generally occur along a

fault.

28. Seafloor Crust

found in the Atlantic ocean between North America and Europe is composed of dense and relatively young rock

16. which of the four spheres of Earth is the most extensive?

geosphere

28. Old faithful Geyser at Yellowstone National park in the United States acquires its energy from a

hot spot

2. A(n) ___ is a tentative explanation, whereas a(n) ____ has survived extensive scrutiny over many years.

hypothesis; theory

22. Earth's Surface

lava cooling and undergoing crystallization to form extrusive igneous rocks, weathering, transport, deposition

33. How do plates move at divergent plate boundaries and what forms at them?

Plates move apart, new oceanic lithosphere

33. How do plates move at convergent boundaries?

Plates move toward one another

30. What evidence supports that the glaciers on the southern continents were once part of a single, massive ice sheet?

Striations

13. What property of the crust allowed it to form as the exterior of Earth?

materials that make up the crust are less dense and rose to the top

32. What is the main material being subducted at an ocean-continent convergent boundary?

oceanic lithosphere

33. In general, where do volcanoes form in subduction zones?

on the overriding plate, away form the convergent boundary

18. The ________ is a layer of liquid nickel and iron believed to be responsible for generating the Earth's magnetic field.

outer crust

32. Oceanic lithosphere contains oceanic crust and the (blank)

outermost part of mantle beneath the oceanic crust

33. How do plates move at transform plate boundaries?

plates slide past one another

22. Earth's deep subsurface

rock melting, high temperature, high pressure (high-grade) metamorphism

28. The slowly increasing distance between South American and Africa is due to

seafloor spreading

22. Earth's shallow subsurface

sediment undergoing lithification

22. Which of the following rock types is most abundant on Earth's land surface?

sedimentary rocks

12. What is the definition of differentiation?

separation of materials based on density

6. The stable interior of a continent is called a ____.

shield

28. The extremely deep ocean Marianas Trench is a result of

subduction

24. (Blank) is an example of a feature associated with an oceanic- continental convergent plate boundary?

the Cascade Mountain Range

14. The largest layer (by volume) of Earth, ____, is composed primarily of _____.

the mantle, periodite

30. Late Paleozoic sedimentary rocks often contain extensive coal seams that were used to support the existence of Pangaea. What would the climate have been at that time and at that location where the coal deposits were formed, and what would it indicate about the continents past latitude?

warm, humid climate near the equator

5. Sedimentary rocks are formed from igneous rocks beginning with the process of _____.

weathering

27.Which of the following can be used to measure the rate of plate motion?

The age of the sea floor, GPS satellites

32. What are two differences between oceanic crust and continental crust?

The continental crust is thicker and less dense than oceanic crust

30. When matching up once joined continents such as South America and Africa, the coastlines do not fit together as nicely as the continental shelves. Why might this be the case?

The continental shelves are the edges of the continent. The shoreline simply shows where the sea level is in relation to topography.

29. Which was was indirectly responsible for the development of the more modern tools that made the theory of Plate Tectonics possible?

World War 2

37. How will the age and temperature of the subducting plate affect its angle of descent?

Younger and warmer plates will have a shallow angle of descent

7. Which one of the following is a natural disaster?

a landslide striking San Fransisco

17. Which of the following materials can be used to make interpretations about the nature and composition of the interior of the Earth? Meteorites Slivers of crustal and mantle rocks exposed at the surface Diamond-bearing pipes All of the above None of the above

all of the above