Geology Exam #1 Flashcards
What was the geocentric model of the universe?
A geocentric Model of a Universe thats say the earth is placed in the center of the universe
What did it The geocentric model account for?
That the Earth is stationary. The plants sun and star all revolve around the earth
what are the three rule for defining a planet
It must Orbit a star,It must be big enough to have enough gravity to force it into a spherical shape, It must be big enough that its gravity has cleared away any other objects of a similar size near its orbit around the Sun.
What are the main differences between Terrestrial and Jovian planets?
Terrestrial Planet are rocky and large while Jovian Planets are small and are gas formed
What are the major ways in which the Earth gets/has gotten its internal heat?
The heat from when the planet formed, The heat from radioactive decay, and other radioactive elemements
What are Earth’s mechanical layers?
Lithosphere, asthensopshere, lower mantle, outer core, and inner core
What are Earth’s compositional layers?
core mantle and crust
How does pressure and temperature change when
moving into the Earth’s interior?
The temperature and the pressure both increase as we go deeper within the Earth, toward its core.
What are the main elements that compose the earth
ron, oxygen, silicon, and magnesium
Plastic vs. elastic vs. brittle deformation
Elastic=temporary
plastic=permanent
rupture=rock breaks while undergoing elastic strain
Magnetic poles
is the point where the lines of force of the Earth’s magnetic field converge.
Geographic poles
is the end of the Earth’s rotation axis and is the North on geographic maps.
What interior portion of the
Earth is responsible for the magnetic field generation?
the fluid outer core by a self-exciting dynamo process
What is the general structure/layers of our atmosphere?
troposhphere, stratosphere, mesosphere, thermosphere, and exosphere
What is the most abundant
gas in our atmosphere?
nitrogen
What are Earth’s principal greenhouse gases?
carbon dioxide, methane, nitrous oxide, and various synthetic chemicals
What does the ozone layer do for us?
absorbs a portion of the radiation from the sun, preventing it from reaching the planet’s surface.
On which plate do volcanoes form at a subduction zone?
Oceanic Plate
What main factors and theories does the theory of plate tectonics explain/support?
how major landforms are created as a result of Earth’s subterranean movements.
What were Wegener’s lines of evidence for continental drift?
fit of the continents, paleoclimate indicators, truncated geologic features, and fossils.
Which two layers of Earth compose tectonic plates
crust and upper mantle
oceanic crust?
is thinner and denser,
The continental crust
is thicker and less dense
Why is there no earthquake activity below about 670 km at a subduction zone?
the subducting plate is not brittle anymore and has become hot enough to flow plastically.
What class of minerals is the most abundant on Earth?
Feldspars
What is the 6-part definition of a mineral?
1) naturally occurring, 2) inorganic, 3) solid at room temperature, 4) regular crystal structure, and 5) defined chemical composition.
What are polymorphs?
a mineral with the same chemical composition but a different internal structure.
In what 2 major ways do mineral crystals grow?
- crystallization of magma (cools inside the crust) or lava (cools & hardens on the surface) 2. crystallization of materials dissolved in water. When these liquids cool to a solid state, they form crystals
Why can we not always rely on color to help us figure out what a mineral is?
because color can be highly variable. Some minerals can occur in a variety of different colors due to impurities in the chemical makeup of the mineral.
anhedral crystals?
refers to the lack of crystal faces on a particular mineral specimen.
euhedral crystals
, where the mineral specimen shows flat, well delineated crystal surface features
Name a couple of minerals that are soft, and a couple that are harder than glass.
Quartz is hard, Calcite is soft,
fractional crystallization
Fractional crystallization is a geological process of crystallization and removal of different minerals from the cooling magma.
Partial melting
Partial melting is a geological process in which different minerals in the rock melt in different temperatures.
How does the cooling of a rock affect the grain size/texture
slow cooling allows large crystals to form, fast cooling yields small crystals.
viscosity
a key property that affects how rocks deform and flow under stress,
What are the 4 main intrusive igneous rock types, and their extrusive counterparts?
granite, diorite, gabbro, and peridotite.
What is an example of a glassy igneous rock,
basalt, andesite, and rhyolite
example of a pyroclastic igneous
rock?
.
Pumice, scoria, and cinders
What are the three types of volcanoes?
cinder cones, composite volcanoes , and shield volcanoes.
What factors make a volcano explosive vs. effusive?
he amount of gas in the magma.
Which types of volcanoes are polygenetic?
Composite volcanoes, shield volcanoes, and calderas
Which types of volcanoes are monogenetic??
cinder cones and fissure volcanoes
What is a pluton?
a body of intrusive igneous rock.
What is a batholith?
a very large igneous intrusion extending deep in the earth’s crust.
What are dike rocks
tabular or sheet-like bodies of magma that cut through and across the layering of adjacent rocks.
What are still rocks
a tabular sheet intrusion that has intruded between older layers of sedimentary rock
What are vesicles?
small cellular containers
