Ch. 12 the dynamic planet
There are two types of time, which are _____ and ______
Absolute and relative
At which of the following locations does subduction occur?
Along collision zones between continental and oceanic plates.
List four evidences Wegener used to prove his hypothesis _____,______, _______, and _____.
Coastlines, fossils, rock types/ mountain belts, and ancient climates
Convergent plates boundaries are characteristics of
Collision zones between plates
In 1912, German geophysicist and meteorologist, Alfred Wegener first proposed the ______ hypothesis about the earth's landmass migration.
Continental drift
List three types of plate boundaries ______, ______, and _____.
Convergent, divergent, and transform
Which of the following gives the correct sequence of layers in the earth, from the surface to the center?
Crust, asthenosphere, lower mantle, core
Which of the following lists the correct sequence of divisions in the geologic time scale, from smallest to largest?
Eon, era, period, epoch
Radioactivity dating only can be used to measure relative time.
False
Since the core's mass is about the third of Earth's entire mass, the value 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 the heat above it.
False
The oceanic crust is less dense than the continental crust.
False
Which of the following plays a role in the shaping of Earth's surface?
Gravity, the act of wind water and ice, the radioactive decay of Atoms, and all of the above
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 youngest epoch in the geologic time scale is ________
Holocene
The transportation and deposition of materials by media powered by solar energy is the
Hydrologic cycle
Three basic rock types are ____(fire-formed, molten),____ (from settling out), and ______ (transformed from any other rock through extreme heat or pressure).
Igneous, sedimentary, and metamorphic
Knowledge of Earth's interior is derived from
Indirect evidence involving the analysis of seismic waves
Earth's magnetic field
Is variable, and has phased to zero some nine times during the past 4 million years
The principles 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, it carries the lithospheric plates, all of the above are true
Which later of planet forms 80% of earth's total volume, and has and average density of 4.5 g/cm3.
Mantle
Which of the following gives the correct sequence of layers in the mantle, from bottom to top?
Mental; upper mantle; asthenosphere
Two most abundant chemical elements in earth's crust are ____ and _____.
Oxygen and silicon
Wegener used _____ to name a supercontinent approximately 225 million years ago.
Pangea
The asthenosphere can be described as
Plastic like
Which of the following is incorrectly matched?
Radioactive decay heat exogenic energy source
Several large, linear lakes are formed in East Africa. This is evidence of what process?
Rifting
Divergent plate boundaries are characteristics of
Sea-floor spreading centers
The earth's dominant materials are ___ and _____
Silica and Iron
When geologist or archaeologist dig downward into a unit of rock or sediment, they are digging "back in time". This fact is based on the principle of ____
Superposition
Heat energy and new materials are brought to the surface by the
Tectonic cycle
The geologic cycle is composed of three subsystems: _____,______, and _______
Tectonic cycle, rock cycle, and hydrologic cycle.
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 than the Kaibob formation
Which of the following statements about the Earth's core is not true?
The inner core is believed to be liquid in the outer core solid
Depth of earthquake focus increases with increasing distance from ocean trench.
True
Earth was once in a molten state, during which materials became sorted based on density.
True
Ocean floor subduction under continents because the ocean floor is denser than continental material.
True
The Hawaiian Islands were formed as a result of a plume of magma from the mantle.
True
The Moho mirrors the surface topography, I.e., high places in the surface of the earth overlies areas in which the Moho descends to greater depths, and versa.
True
The age of the sea flirt increases with increasing distance from a mid-ocean ridge.
True
The fluid outer core generates 90% of Earth's magnetic field.
True
The magnetic stripes found around mid-Atlantic ridge were due to magnetic reversal.
True
Uniformitarianism assumes that the same physical processes we see today are a key to understand the process that have been operating throughout the geologic time.
True
Which of the following is an endogenic process?
Volcanism
Which of the following are locating along the mid-ocean ridge?
Volcanoes
Which of the following is an exogenic process?
Weathering
The oceanic crust thickness is about_____km, and the average continental crust thickness is __km
5, 30