Geology 1100 Mizzou Sandvol Final HW #1

The island of Hawaii is the youngest, and the islands get progressively older to the northwest. Plate tectonic theory explains this as

a hot spot currently sitting under Hawaii and the Pacific plate moving across it in a northwesterly direction

According to nebular theory, the progression from planetesimal to full-fledged planet is propelled mainly by which of the following?

gravity

Alfred Wegener's idea of continetal drift was rejected by American geologists because

he could not conceive of a valid mechanism that would cause continents to shift positions

Magnetic anomalies are

places where the magnetic field strength is either greater or less than the expected strength

According to current plate tectonics theory

plates are composed of the crust and the uppermost part of the mantle

The apparent tendency of the north (or south) magnetic pole to vary in position over time is termed

polar wander

During WW2, the military imaged the seafloor by sending pulses of sound waves down through the water and measuring the time it took for the sound to bounce off the seafloor and return to the receiver. This method is called

sonar

The reversals of the Earth's magnetic field were first discovered by

studying the paleomagnetism of Volcanic rocks

The Earth's magnetic field is created by

the flow of liquid iron in the Earth's molten outer core

The global occurrence of earthquakes reveals that

they usually occur on the boundaries of plates or at hot spots

Order the steps of volcanic island arc formation

1. A subduction trench forms where the subducting plate bends downward into the mantle 2.An accretionary prism begins to form. 3. Magma, created by flux melting of the mantle, rises through the overriding plate. 4. Lava erupts onto the surface, forming volcanoes.

Order the steps of continental volcanic arc formation

1. A subduction trench forms where the subducting plate bends downward into the mantle. 2. An accretionary prism begins to form 3. Magma, created by flux melting of the mantle, rises through the continental lithosphere. 4. Lava erupts onto the surface, forming volcanoes

Smallest to Largest objects in the solar system

1. Asteroid 2. Mars 3. Earth 4. Jupiter 5. Sun

Select statements true of fracture zones

1. Fracture zones can act as transform boundaries between two actively spreading ridge segments 2. Earthquakes can occur along fracture zones 3. Fracture zones are situated perpendicular to mid-ocean ridge segments

Rank the following bodies from largest to smallest

1. Planet 2. Protoplanet 3. Planetsimal

Which of the following variables could influence the width of marine magnetic anomalies on the floor of the ocean?

1. Rate at which the plates are moving away from the mid-ocean ridge 2. duration of the magnetic polarity event

order the steps that lead to seafloor spreading

1. The asthenosphere beneath diverging plates rises and melts 2. A magma chamber forms beneath the ridge axis 3. Magma rises to the surface and erupts via submarine volcanoes. 4. Newly formed crust is moved laterally away from the ridge

According to the theory of plate tectonics, the plates are:

1. discrete pieces of lithosphere which move with respect to one another 2. moved by the creation of new crust and subduction of old crust

Based on the Narrative Art Video about the formation of the Solar System, identify ways in which heavier elements form

1. in stars 2. during supernovae explosions

Modern plate tectonic theory was developed in what decade?

1960s

Which of the following statements regarding the Big Bang theory are True?

All matter in the Universe was once confined to a single point. The universe is considerably older than Earth

The oldest seafloor is generally less than 200 million years old. Why?

All oceanic lithosphere eventually gets subducted beneath the continents by the time it is 200 million years old.

Two atoms combining during Nuclear fusion

Deuterium+Tritium=Helium + ejected neutron

The____ concept placed Earth at the center of the Universe, with the other planets and the Sun revolving around it. The ____concept placed the Sun as the center, with Earth and the other planets revolving around it.

Geocentric; heliocentric

Identify the statement that is true about the Big Bang

It began with all matter and energy concentrated in an infinitesimally small point

Plate movement is influenced by each of the following except

Mantle plumes, which are created when hot rock rises up from the deep mantle and creates melting at the base of the lithosphere

What is the stream of charged particles given off from the sun called?

Solar winds

Which of the following statements about differentiation are true?

The core formed as a result of differentiation. The mantle formed as a result of differentiation

Of the choices below, select the one that accurately pairs the feature with the type of plate boundary at which it occurs

Trenches occur at subduction zones

Positive magnetic anomalies occur where seafloor basalt has the same polarity as Earth's present-day magnetic field

True

Some magma generated during seafloor spreading erupts from submarine volcanoes to form basalt

True

The composition of the giant (Jovian) planets is mainly gas and "ice"

True

Which of the following features protects Earth against high-energy cosmic radiation and very fast-moving solar wind particles?

Van Allen radiation belts

Which of the following issues initially prevented widespread acceptance of Alfred Wegener's continental drift hypothesis?

Wegener's lack of a good mechanism to explain why the continents moved

The Himalayas are growing because

a continental plate is colliding with another continental plate there

Seafloor spreading is driven by volcanic activity that occurs

along mid-ocean ridges

A seamount chain is

an elongates series of former volcanic islands that poke up from the ocean floor

Wegener's theory of continental drift took decades to be accepted

because Wegener couldn't explain how continents moved

The rate of plate motion

can be expressed as relative plate velocity, which describes movement of one plate in relation to another plate

Alfred Wegener proposed the idea of continental drift after he observed evidence from fossils, glacial deposits, and the fit of the continents that suggested all of the continents were once

combined to form a supercontinent (which he termed Pangaea) in the late Paleozoic through the Mesozoic

Marine magnetic anomalies result from seafloor spreading in conjunction with

magnetic polarity reversals

The center of a mid-ocean ridge is where

new oceanic lithosphere is created

The San Andreas fault is

one of the few transform faults that cut across continental lithosphere

The heliocentric model

was supported by observations that planets follow an elliptical orbit