GEOG 1710 Exam 3

________threshold is the point at which there is enough energy to overcome resistance against movements.

Geomorphic

Which of the following plays a role in the shaping of Earth's surface?

Gravity; the action of wind,water,ice; and the radioactive decay of atoms

The youngest epoch in the geologic time scale is the?

Holocene

Volcanic activity located away from plate boundaries is associated with

Hot spots

The geologic cycle is composed of three subsystems:

Hydrologic, Rock, and Tectonic

Which of the following statements about Earth's core is not true?

The inner core is believed to be liquid and the outer core solid.

which of the following is true of the earthquake in the Liaoning Province of NE China on February 4, 1975?

The quake was successfully forecasted and 3 million people were evacuated

A hypsographic curve is a graph that shows the Earth's surface by area and elevation in relation to sea level

True

A residual "synclinal ridge" may form within a trough of a fold.

True

Depth of earthquake focus increases with distance from ocean trench

True

Earth was once in a molten state, during which materials became sorted based on density.

True

Ocean floor subjects under continents because the ocean floor is denser than continental materials.

True

Orogeny means mountain generating.

True

The Hawaiian Islands were formed as a result of a rising plume of magma from the mantle.

True

The Moho mirror the surface topography, i.e., high places on the surface of the Earth overlies areas in which the Moho descends to greater depths, and vice versa.

True

The age of the sea floor increases with increasing distance from a mid-ocean ridge.

True

The angle of response depends on the size and texture of the grains

True

The fluid outer core generates 90% of Earths magnetic field.

True

The magnetic stripes found around mid atlantic ridge were due to the magnetic reversal

True

The mean sea level is at 0m.

True

The pressure-release jointing is a physical weathering process that does not involve water

True

The salt crystal growth is primarily found in arid environments

True

Which of the following is an endogenic process?

Volcanism

Which of the following are located along the mid-ocean ridge?

Volcanoes

When rock strata are strained beyond their ability to remain an intact unit, displacement occurs in a process known as

faulting

The motion of seismic waves is initiated in a subsurface location where seismic waves are initiated is

focus, or hypocenter

On which part of a slope would rocks tend to fall at the highest speed?

free face

List three forms of physical weathering

frostaction, salt crystal, and pressure release

The decay rate is expressed as _____, the time required for one half of the unstable atoms in a sample to decay into "daughter" isotopes.

half-life

The transportation and deposition of materials by media powered by solar energy is the

hydrologic cycle

Approximately what percentage of Earth's surface is exposed above sea level?

29%

Convergent plates boundaries are characteristics of

Collision zones between plates

List four volcanic activity zones:

Continental rift valley, oceanic-continental plate convergent, oceanic-oceanic plate convergent, sea-floor spreading

The principle of buoyancy and balance, when applied to Earth's crust, helps us to explain fluctuations in Earth's outer crust, a property known as

Isostatic adjustment

Which of the following is true of the asthenosphere?

It contains pockets of increased heat; it flows; and it carries the lithospheric plates

The dynamic equilibrium model refers to

a balancing act between tectonic uplift and rates of denudation by weathering and erosion in a given landscape

Movement at the geomorphic threshold signals

a conversion of potential energy to kinetic energy

The area at the surface directly above the subsurface location where seismic waves are initiated is termed the

epicenter

Normal faults are associated with

tension forces

List two forms of landslides

transitional and rotational

A landslide differs from a debris avalanche in the

A landslide moves more slowly than a debris avalanche

Landslides occur when

A threshold is reached; the internal friction is overcome by the force of gravity; driving forces exceed resisting forces

There are two types of time, which are?

Absolute and Relative

After a threshold is crossed, the landscape

Adjust to a new equilibrium condition

List four Earth's continental shields

African , Australian, Baltic, and Indian

At which of the following locations does subduction occur?

Along collision zones between continental and oceanic plates

In 1912, German geophysicist and meteorologist, Alfred Wegener first proposed the ____________ hypothesis about the Earth's land mass migration.

Continental Drift

A _________, or heartland region, is an old and stable part of the continental crust.

Craton

List three types of plate boundaries

Divergent, Convergent, and transform

Since the core's mass is about one third of Earth's entire mass, the volume of the core is also of one third of the earth's entire volume.

False

The density of material below the Moho is less than that above it.

False

The moment magnitude scale is based on energy released and is less accurate than Richter's scale which is based on the amplitude of seismic waves.

False

The oceanic crust is less dense than the continental crust.

False

Which of the following can lead to hillslope failure?

Making a road cut in the side of a hill; increasing the slope angle; excessively watering a slope

Which layer of planet forms 80% of Earth's total volume, and has an average density of 4.5 g/cm3.

Mantle

People often say that California is going to "fall into the ocean". This idea is total wrong because the San Andreas fault would have to be a ________ fault associated with _________ forces for this to happen.

Normal; tension

List three types of ogresses:

Oceanic-oceanic collision, oceanic-continental collision, continental-continental collision

in reality, a landscape behaves as a ________ system

Open

Wegener used _______ to name a supercontinent approximately 225 million years ago.

Pangaea

When rock is broken and disintegrated without dissolving, the process in operation is

Physical weathering

Uplift of the landscape creates_____ energy which is converted to ________ energy when materials begin to move downslope.

Potential; Kinetic

Several large, linear lakes are formed in East Africa. This is evidence of what process?

Rifting

A continental ________is a region with a craton is exposed at the surface.

Shield

If you were paranoid of earthquakes, which of the following area would be the safest to live?

Shield

The San Andreas system in california is an example of a

Strike-slip fault;transform fault; right-lateral motions

When geologists or archaeologists dig downward into a unit of rock or sediment, they are digging "back in time". This fact is based on the principle of?

Superposition

Which of the following is not an example of an age-relationship based on absolute dating?

The Coconino formation in the Grand Canyon is older that the Kaibab formation

Uniformitarianism assumes that the same physical processes we see today are a key to understand the processes that have been operating throughout the geologic time.

True

A slope is stable if its strength exceeds the weathering and erosion process

Truth

Other than the rock itself, the most important chemical substance needed for the majority of weathering processes is

Water

Which of the following is an exogenic process?

Weathering

The most active tectonic regions of North and South America are on the

Western Coasts

Folded layers of rock can form a wavelike pattern of troughs and crests. The layers near the crest form

an anticline

Which of the following is an example of a first order of relief?

an ocean basin

The steepness of a slope made of loose material is called the

angle of response

Chemical weathering is greatest under conditions of

higher mean annual rainfall and temperature

In which climate would rock be weathered to the greatest depth?

hot and wet

Three basic rock types are_____(fire-formed,molten),______(from settling out), and________(transformed from any other rock through extreme heat or pressure).

igneous, sedimentary, metamorphic

Knowledge of Earth's interior is derived from?

indirect evidence involving the analysis of seismic waves

Earth's magnetic field

is variable, and it has phased to zero some nine times during the past 4 million years

Which of the following is true of spheroidal weathering?

it attacks the corners and edges of rocks

Which of the following is true of joints

joints enable more water to move through the ground; joints enhance the rate of weathering

An example of chemical weathering is

karst topography

Which of the following gives the correct sequence of layers in the mantle, from bottom to top?

mantle; upper mantle; asthenosphere

Exfoliation occurs because

overlaying rock is removed, thereby allowing the underlying rock mass to expand and fracture

Two most abundant chemical elements in Earth's crust are?

oxygen and silicon

Which of the following is incorrectly matched?

radioactive decay heat-exogenic energy source

In most areas, the upper surface of bedrock is partially weathered to broken-up rock called

regolith

Vertical elevation differences in a local landscape are referred to as

relief

List two types of scale to rate earthquakes

richter and moment magnitude

Human-induced mass movements produce a category of processes known as

scarification

Divergent plate boundaries are characteristics of

sea-floor spreading centers

An instrument used to record vibrations in the crust is

seismograph

Which of the following is incorrectly matched?

shearing---stretching

A slow persistent mass movement of surface soil is called

soil creep

The combination effects of _____(powered by internal energy) and_______(powered by the sun through motion of air,water and ice) create Earth's continental crust.

tectonic activity; Weathering and erosion

Heat energy and new materials are brought to the surface from the interior by the

tectonic cycle

Rocks are subjected to stress due to

tectonic forces; gravity, and pressure from underlaying rocks

List three types of stress

tension, compression, and shear

The rate at which rocks weathering depends on

the climate of an area, the type of rock, and the amount of vegetation in an area

The most detailed order to relief applies to ______ order relief features

third

The disintegration and dissolving of surface and subsurface rock is called

weathering

The Earth's dominant materials are?

Silicone and Iron

Physical weathering dominates in warm and wet climates

False

Radioactive dating only can be used to measure relative time.

False

The asthenosphere can be described as

plastic-like

The oceanic crust thickness is about ______ km, and the average continental crust thickness is ______ km.

5;30

List four evidences Wegener used to prove his hypothesis

Coastal line, fossils, rock types, and mountain belts

Which of the following gives the correct sequence of layers in the Earth, from the surface to the center?

crust, asthenosphere, lower mantle, core

All processes that cause reduction and rearrangement of landforms are included in the term of

denudation

Which of the following lists the correct sequence of divisions in the geologic time scale, from largest to smallest?

eon,era,period,epoch

The form that a landscape exhibits results from a balance between

forces acting on the landscape; endogenic and exogenic processes; input and outputs of matter and energy

Compared to oceanic crust, continental crust is

generally more complex on content and structure

The science that specifically studies the orgin, evolution, form, and spatial distribution of landforms is

geomorphology