Chapter 4 - The Earth Speaks
The assumption that current natural, earth-shaping processes also shaped the earth in the past at the same rate.
Uniformitarianism
Geologists determine the relative date of a rock layer by applying the principle of ___________________.
Superposition
The difference between the focus and the epicenter of an earthquake.
The focus is the point underground where the earthquake originates; the epicenter is at the surface, directly above the focus.
Trenches, volcanic arcs, and fold mountains are typical landforms for which type of tectonic boundary?
Convergent Boundary
Another name for the Circum-Pacific volcano belt.
What is the Ring of Fire?
A characteristic (we studied many) of the earth that is an evidence for design.
Earth's mass and structure, tilt and rotation, liquid water, atmosphere, magnetic field, sun, place in the solar system, and place in the Milky Way.
Explain the differences between a young and old earth perspective on planetary formation.
Old Earth: The Nebular Hypothesis says that gravity formed planets from dust and gas, according to the nebular hypothesis.
Young Earth: God created the planets, including the Earth.
Name two places that rift valleys are located.
Mid-ocean ridges and East Africa
Subduction occurs when _______________.
One tectonic place slides under another.
This type of volcano has the steepest sides of the three types we studied.
What are cinder cone volcanoes?
The state of matter of the outer core of the earth and why scientists believe this to be so.
Liquid because S waves do not pass through it.
The differences in a young and old earth perspective on the formation of continents and the geologic column.
Old Earth: Continents moved over millions of years, and the geologic column formed over billions of years.
Name the three types of plate boundaries and explain what is occurring at each.
Divergent: plates are moving apart; new crust is being created as magma comes up and hardens
Convergent: plates are coming together; crust is being destroyed as it is being subducted or folded.
Transform: plates are sliding past each other
The ability of wind and water to carry sediments is directly related to the _________________ of flow.
Speed. The faster the movement, the more sediment that wind and water can carry.
Volcanoes are an example of ___________ volcanism, while sills and dikes are an example of ___________ volcanism.
What are examples of extrusive volcanism and intrusive volcanism?
Explain why the tilt of the earth is important.
If the earth was not tilted in its orbit, the equator would be very hot while the poles were very cold, there would be no seasons, and all living things would be crowded into smaller habitable areas between the poles and the Equator.
Explain the differences in a young earth and old earth perspective on ice ages.
Old Earth: Earth’s history includes many ice ages over billions of years.
Young Earth: There was a single Ice Age after the Flood.
Explain the differences between P-waves, S-waves, and surface waves.
P-waves: The first waves to arrive at an earthquake station as they are the fastest. They have a smaller amplitude and shorter wavelength and can travel through both liquids and solids.
S-waves: The second waves to arrive at an earthquake station. They are both stronger and slower than P-waves, and do not travel through the core of the earth.
Surface waves: travel along the earth's surface; the most destructive type of wave.
How geologists explain the presence of many mountain landforms near the boundaries of tectonic plates
What are tectonic plates converging or diverging, causing mountains to form? Converging plates push mountains up, while diverging plates fracture the crust as they pull apart
The three main types of lava we studied and the difference between them.
Rhyolitic - lighter in color and very thick; has the highest silica content.
Andesitic - Less thick than rhyolitic lava with a lower silica content.
Basaltic - the least viscous (thick) of the three.
What special protective feature do geologists believe originates deep withtin the earth, most likely within the core?
The earth's magnetic field
The order in which we find creatures in the geologic column and how Flood geologists explain this placement.
What is from least complex to most complex as you gain elevation? The least complex organisms would be buried by the flood first, as they are smaller and not as strong. More complex organisms would be able to get to higher ground, with the most complex organisms being buried last.
Explain how scientists pinpoint an earthquake's epicenter.
Data is needed from three seismic stations. Each station uses the difference in arrival time of P and S waves in order to calculate its distance from the epicenter. These distances are used to draw circles around each station; the epicenter is where these circles all meet.
The definition of an area's topography.
What is an area's variety of elevations and arrangement of landforms?
The differences/similarities between the shield, cinder cone, and stratovolcanoes.
Shield volcanoes have a very gradual slope and are formed by basaltic lava such as pahoehoe and a'a lavas.
Cinder cone volcanoes are formed by gaseous eruptions, ejecting ashes, cinders, and bombs (tephra). They are small and have relatively steep slopes.
Stratovolcanoes are formed by alternating eruptions: quiet eruptions produce lava layers, while gaseous, explosive eruptions produce the layers of tephra.