Geology 101 Quiz 1 Flashcards
what is often the only way we know countries have developed nuclear capabilities?
geophysicists can tell the difference between seismic waves caused by earthquakes vs caused by nuclear blasts
geological engineers often determine
how stable a slope is
in places like ?, space is so limited that people build on unstable slopes
Hong Kong
petroleum geologists
find the best places to drill for oil or natural gas
hydrogeologists/geochemists
determine where groundwater contaminants come from, where and how far they are likely to travel, and how best to clean (this is the professor’s interest)
paleoclimatologists
primary scientists involved in what ancient climate looked like on Earth and why climate changes; info gathered is used to predict how the present climate may be influenced by things
volcanologists
predict if a volcano will erupt and whether it is likely to be a simple lava flow (like Hawaii) or an explosive eruption (like Mt. St. Helens)
what gives different types of rocks their unique qualities?
they are made of very different materials and by different processes
which stone is more concerning for a sinkhole? (granite/limestone)
limestone
when making sandpaper, mining for (corundum/gypsum) will be more profitable
corundum
oil is more likely to be found in (sandstone/basalt)
sandstone
cosmology
the study of the origin and makeup of the universe
in the early 1900s, most thought the universe was
static and infinite; motions such as orbits were recognized, but the relative positions of distant galaxies was thought to be fixed (static) and the extent of the universe was thought to be without limit (infinite)
? developed an elegant mathematical model that allowed accurate prediction of everything from orbital paths to the ability of gravity to bend space (and thus radiation traveling through space)
Albert Einstein
Albert Einstein’s mathematical model indicated an
expanding universe
Einstein inserted the cosmological constant into the equation because
the idea of the universe having a beginning was unsettling; seemed to require a non-scientific explanation
later called this constant the biggest mistake of his career
over the next 15 years, data from astronomers such as ? showed that distant galaxies were moving ?
Edwin Hubble; away from us very fast in every direction
singularity
the universe in a dimensionless point - some debate over nature of initial starting point
during the first million years of the universe,
subatomic particles combine to make Hydrogen
during the first billion years of the universe,
gravitational attraction separates matter into galaxies
in stars, heat is high enough to initiate
nuclear ignition
3 types of heat generation
collisions, compression, radioactive decay
nuclear ignition
NOT like igniting a fire; intense pressure and heat results in two atoms combining into a singular new atom (fusion); part of the mass of the combining atoms is converted into energy (radiation/heat)
collisions
particles striking each other increase the kinetic energy which generates heat
compression
air compressors get hot as the air is compressed; aerosol cans get cold as the gas inside expands
radioactive decay
planets cool slower than otherwise expected because radioactive elements release heat as they decay
supernova
collapse and explosion of large stars; heaviest elements produced
our solar system is thought to be a second generation system because (2 reasons)
- lots of elements present are heavier than iron (Fe)
2. the age of the oldest rocks (~4.6 billion yrs) is younger than the calculated age of the universe (~13.8 billion yrs)
according to modern cosmology, the universe originated from a
void
differentiation
refers to a separation into layers with unique properties
differentiation happens because
materials that are more dense will tend to sink toward the core, and materials that are less dense will rise toward the surface
Earth’s layers (from outer to inner)
continental crust, oceanic crust, mantle, outer core, inner core
Earth’s layers - lowest density, solid, rigid
continental crust
Earth’s layers - high density, solid Fe and Ni
inner core
Earth’s layers - intermediate density, semi-fluid
mantle
Earth’s layers - high density, liquid Fe and Ni
outer core
Earth’s layers - lower density mantle minerals, solid, rigid
oceanic crust
minerals found in the earth’s crust are grouped into two categories
felsic and mafic
felsic
lower density, lighter in color; continental crust
mafic
higher density, darker in color; oceanic crust
why does the oceanic crust sit lower?
its more dense and thinner
water is thought to have come from 3 sources:
- condensation of water vapor as earth cooled (goes to surface during differentiation)
- comet collisions with earth (b/c comets contain a lot of water)
- volcanism (gas from eruptions is mostly water because water vapor is dissolved into magma)
condensed water will accumulate in lowest areas, which is mostly over ?
oceanic crust (although oceanic crust is NOT defined by having water over it; water covers edges of continental crust as well, and oceanic continues underneath continental)
the ? and ? form a somewhat rigid layer that moves laterally over the rest of the mantle, which is more plastic
crust and uppermost portion of the mantle
lithosphere
the rigid layer that moves as a unit (crust and uppermost mantle)
asthenosphere
the region of the upper mantle below the lithosphere
variances in heat in the mantle cause ? within the asthenosphere
convection currents
convection refers to
the movement of material in response to some force; in this case, movement is caused by the rise of hotter regions of the mantle and falling of cooler regions
the crust is solid, so if any portion of the crust moves, it will run into other solid crust, which results in
breaks in crust
plates
portions of unbroken crust
plate tectonics (AKA continental drift)
the study of the movement of these plates
individual plates can be made up of
just oceanic crust, just continental crust, or a combination of both
there are currently about ? large plates
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