EAPS 106 Homework #1

1.11. In Wikipedia, look up "Transform fault" and answer this question: What is a transform fault or transform boundary (sometimes called a strike-slip boundary)?

A fault along a plate boundary where the motion is predominantly horizontal.

1.9. In Wikipedia, look up "Seafloor spreading" and answer this question: What is seafloor spreading?

A process that occurs at mid-ocean ridges where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge.

1.20. In Wikipedia, look up "Diamond" and answer this question: At what depth do most diamonds originate from and how do they get to the surface?

Between 150 and 250 km depth and come to the surface in Kimberlite volcanic eruptions.

1.2. In Wikipedia, look up "History of Earth" and answer this question: How did the Earth form?

By accretion from the solar nebula

1.18. In Wikipedia, look up "Geode" and answer this question: How does a geode form?

By the filling of vesicles (voids) in rocks by minerals deposited from the passage of fluids.

1.16. In Wikipedia, look up "Earth's magnetic field" and answer this question: True or false: The north pole of Earth's magnetic field is located in Earth's northern hemisphere.

False

1.3. In Wikipedia, look up "Geothermal gradient" and answer this question: A young Earth was hot enough inside to melt. How did the Earth obtain the heat in its interior?

From radioactive decay, residual heat from planetary accretion, and Latent heat from core crystallization

1.6. In Wikipedia, look up "Lithosphere" and answer this question: Which statement about Earth's lithosphere is correct?

It includes the crust and the uppermost mantle, which constitutes the hard and rigid outer layer of the Earth.

1.7. In Wikipedia, look up "Asthenosphere" and answer this question: What is asthenosphere?

It is the mechanically weak layer of the upper mantle that lies just below the lithosphere.

1.10. In Wikipedia, look up "Subduction" and answer this question: What is a subduction?

It is where oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries.

1.8. In Wikipedia, look up "Continental drift" and answer this question: What is the theory (or hypothesis) of continental drift? (Note: this question is purely about continental drift, not plate tectonics.)

That over time the continents move relative to each other

1.5. In Wikipedia, look up "Plate tectonics" and answer this question: Which statement about plate tectonics is correct?

The Earth's lithosphere is comprised a number of large tectonic plates which have been slowly moving since about 3.4 billion years ago. Where the plates meet, their relative motion determines the type of plate boundary: convergent, divergent, or transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along these plate boundaries (or faults). & Tectonic plates are composed of the oceanic lithosphere and the thicker continental lithosphere, each topped by its own kind of crust.

1.13. In Wikipedia, look up "Electromagnet" and answer this question: What happens when the wire turns are wound around a ferromagnetic material?

The magnet gets stronger

1.17. In Wikipedia, look up "Earth's magnetic field" and answer this question: Which of the following statements about Earth magnetic field is true?

The magnetic poles slowly and continuously move

1.1. In Wikipedia, look up "Structure of Earth" and answer this question: Which layer of the Earth is a liquid?

The outer core

1.19. In Wikipedia, look up "Hollow Earth" and answer this question: What is the evidence that the Earth cannot be hollow inside?

The passage of seismic waves requires the Earth to be non-hollow. Gravity does not allow for a planet to form with a hollow interior & Ordinary matter is not strong enough to support a hollow space of planetary size

1.4. In Wikipedia, look up "Planetary differentiation" and answer this question: What is planetary differentiation?

The process by which the chemical elements of a planetary body accumulate in different areas of that body.

1.12. In Wikipedia, look up "Mantle convection" and answer this question: What is a mantle convection?

The slow creeping motion of Earth's solid mantle caused by currents carrying heat from the interior to the planet's surface.

1.14. In Wikipedia, look up "Dynamo theory" and answer this question: How does the Earth generate its magnetic field?

Through the rotation, convection, and electrical conduction within its liquid iron outer core.

1.15. In Wikipedia, look up "Aurora", read the intro then scroll down to "Atmosphere", and answer this question: True or false: The northern and southern lights are caused by emission of photons in Earth's upper atmosphere from ionized (excited) nitrogen and oxygen atoms caused by the solar wind. (Be sure to read both the intro to Auroras as well as the Atmosphere section to answer this question).

True