Which of the following statements regarding the scientific method is true
A theory is a hypothesis that has withstood many scientific tests
How old is the Earth
approximately 4.5 billion years old
The Earth's core is made up primarily of
iron
Which of the following elements is more abundant in the Earth's crust as compared to the Earth as a whole?
silicon
Ninety percent of the Earth is made up of which four elements?
iron, oxygen, silicon, and magnesium
Solar energy energizes all of the following major components of the Earth system except the
lithosphere
In which of the following subsystems is the Earth's magnetic field generated?
hydrologic system
The Earth's climate system involves interactions between the atmosphere and the
biosphere, hydrosphere, and lithosphere
Which of the following relationships is correct
lithosphere = crust + upper mantle
Large continental masses had formed on the Earth by
2.5 billion years ago
When did biology's "Big Bang" (evolutionary explosion) occur?
about 540 million years ago
What caused the mass extinctions 65 million years ago that ended the Age of Dinosaurs?
major bolide impact
Stony meteorites are similar in composition to the Earth's
mantle
The group of meteorites that are similar in composition to the Earth's core are
iron-nickel meteorites
Change in the ground elevation of the Earth's surface is called
topography
Elevation of the ground surface is measured relative to
sea level
The daily rotation of the Earth causes the equatorial regions to _______ and the polar regions to ________.
bulge outward, flatten
The Mohorovicic discontinuity coincides with the __________ boundary.
crust-mantle
The Earth's major layers include (from outermost to innermost) ___________.
crust, mantle, outer core, inner core
The ability of the Earth's atmosphere to retain heat is referred to as the __________.
greenhouse effect
The typical elevation of the land surface occurs within a range of _______ above sea level.
0-1 km
The highest topographic point above sea level on Earth is at ________.
Mount Everest
The average density of continental crust is ________ g/cm3
2.8
Continents float high because they are _______.
less dense than the mantle
Which of the following is not an integral part of the scientific method
belief
In terms of its shape Earth is _______.
flattened at the poles and bulging at the equator
The densest part of the Earth is the _______.
core
The lithosphere is composed of _______
crust and upper mantle
Geologist James Hutton advanced the principle of _______
uniformitarianism
Devices used to detect earthquakes are called
seismometers
The average density of the bulk earth is most similar to that of
iron meteorite (8 g/cc
The largest jump in density within the Earth is at the _______.
mantle-core boundary
Deep time" refers to time measured in _______ of years
billions
Roughly how much exterrestrial material falls on the Earth annually
a million tons
Who proposed the theory of continental drift?
Charles Darwin
Where is new lithosphere created?
divergent plate boundaries
Where does volcanism occur?
divergent plate boundaries transform fault boundaries
New lithosphere is created ____________.
at mid-ocean ridges
Which of the following locations could be represented by the diagram?
the west coast of South America
In which ocean are most of the world's convergent plate margins located?
Pacific Ocean
The east coast of North America is __________
not a plate boundary
Approximately how deep (below sea level) are the deepest deep-sea trenches?
10 km
Which of the following is not associated with convergent plate boundaries?
spreading centers
Which of the following mountain ranges formed as a result of ocean-continent convergence?
the Andes
When a deep-sea trench is located next to a continent, where would you expect to find active volcanoes?
on the continent side of the trench
What type of plate boundary is parallel to the direction of plate movement?
transform plate boundary
The North American Plate is bounded by ______ plate boundaries.
convergent, divergent, and transform
Modern seafloor spreading rates range from _________.
2 to 15 centimeters per year
What two scientists related the positive and negative magnetic bands on the seafloor to seafloor spreading?
F.J. Vine and D.H. Mathews
When was the supercontinent of Pangaea assembled?
approximately 250 million years ago
How old are the oldest rocks on the ocean floor?
about 200 million years old
The oldest continental rocks are __________ than the oldest oceanic rocks.
much older
Isochrons on the seafloor are roughly __________ the ridge axis along which they were created.
parallel to and symmetric about
Why are isochrons on the Pacific seafloor more widely spaced than isochrons on the Atlantic seafloor?
The Pacific seafloor formed at a faster spreading rate than the Atlantic seafloor.
When did India begin to collide with Asia to form the Himalayas?
about 50 million years ago
What drives plate tectonics?
mantle convection
How deep are plates subducted?
2900 km
The Hawaiian volcanoes are __________.
not located at a plate boundary
Mid-ocean ridges are also referred to as _________.
spreading centers
The convergence of the North American Plate with the Juan de Fuca Plate forms the ______ subduction zone.
Cascadia
Mount St. Helens is part of the ____________.
Cascade Range
The Great Rift Valley of East Africa is an early-stage _________.
divergent boundary
Astronomical positioning measures points on the Earth's surface relative to ________.
the position of fixed stars
Fifty million years in the future geoscientists predict the east coast of North America will be _____________.
a convergent plate boundary
The main type of plate boundaries are (proper names only): __________.
convergent, transform, divergent
How do we determine absolute direction of plate movement over millions of years?
with seafloor isochrons
Who first described world tectonics in terms of rigid plates?
Tuzo Wilson
Who first proposed the three different kinds of plate boundaries widely accepted today
Tuzo Wilson
Which of the following locations is least likely to have active volcanoes?
transform fault
How many major plates cover the Earth's surface?
13
Who first suggested that the Earth's surface might be a fragile shell resting on fluid?
Benjamin Franklin
__________ was the first earth scientist to propose a rudimentary form of seafloor spreading?
Arthur Holmes