Geology
What were the elements after H and He
carbon and Iron but mostly iron
How did Nebulae form?
clouds and gas % dust in space
convergent boundary
colliding going towards each other two plates move towards each other
How do planets form?
colliesions cause dust, planetesimals , protoplanets, planets
Isostacy
concept that the lithosphere is floating on the asthenosphere in gravitational equilibrium
Ocean Convergent Boundary
continent - ocean plate sinks down into asthenosphere beneath continental plate
what type of lithosphere floats higher
continental lithosphere since its thicker and less dense
third step of the moon forming
debris condenses and forms the moon
third piece of wagerers evidence
distribution of fossils, restricted range of where animals are and plants
second piece of wegeners evidence
distribution of glacial deposits/ features
How do we know where plate boundaries are?
earthquake belts define positions of plate boundaries
first piece of wagerers evidence
fit of the continents
lithosphere (plates)
floats on asthenosphere
fifth piece of evidence for seafloor spreading
magnetic anomalies symmetric about MOR
1 piece of seafloor spreading evidence
ocean topography - mid ocean ridges - abyssal plains - trenches
how do divergent plate boundaries start?
rifting
what is the lithosphere like?
rigid, strong, brittle, outer layer
Scientific Method
sequence of steps used to analyze scientific methods
what are the inner planets like?
small, dense, and rocky
Is the crust solid or liquid?
solid
Is the mantle solid or liquid?
solid
what is rifting?
stretching/ thinning of continental lithosphere
What are the outter planets?
Jupiter, Saturn, Uranus, Neptune
how old is the earth?
4.5 Ga
What is the core?
Center of the earth
What were the first elements to come from the big bang?
H & He
divergent boundary
two plates move away from each other
transform boundary
two plates slide past each other
earths volume
822
magnetic anomalies symmetric about MOR
- earth has a magnetic field w/ north and south poles - they can concede with geographic poles or they can flip
2nd piece of evidence of seafloor spreading
- sediment accumulation - no sediment at MOR - layer of sediment thickens away from MOR
What are the steps of the scientific method?
1. Make an observation 2. make hypothesis 3. test hypothesis 4. draw conclusions from data 5. reject or accept hypothesis
Doppler effect
An observed change in the frequency of a wave when the source or observer is moving
How do you get a star?
Ball at the center of accretion disk grows hot and dense
How did the universe form?
Big Bang Theory
second step of the moon forming
Blasted debris forms a ring around earth
What compositions make up earth in order
Fe, O, Si, Mg
what produces heavier elements?
Fusion
What are the inner planets?
Mercury, Venus, Earth, Mars
How do you get a spinning accretion disk?
Nebulae condenses into it
Are elements evenly distributed through out earth?
No not at all
Step 1 of the moon forming
Soon after the earth formed, a protoplanet collided with earth
what are the two groups of planets?
Terrestrial and Jovian
oceanic lithosphere
Topped by oceanic crust, thinner & more dense
when did the Big Bang theory occur
about 13.8 Ga
what is mantles density
about 4.5 g/cm
3 piece of evidence of seafloor spreading
age of crust - age of rocks - farther away from MOR
How is there a differentiation of elements?
as inside of earth heated, denser metal sank to the center and lighter materials rose to the surface
how does ocean crust form?
as plates spread, hot asthenosphere risies as it rises part of it melts producing magma magma goes to surface and cools
How does the doppler effect relate to the creation of earth
as time goes by space is expanding
what's the rock type for continental crust
granite
fourth piece of seafloor spreading
heat flow - heat at more - rocks cool farther from MOR
mantle plume:
heat source for hot spots, lithosphere plates are moving at this time and when they move the hot spot is carved off
continental drift
hypothesis that the continents were once joined together and then drifted to where they are now
what part of the core is solid
inner
Where are terrestrial planets located?
inner solar system
What part of the disk is filled with dust
inside
what are the outside planets like?
large, gassy, and ice giants, low density
What did Hubble discover?
light waves from stars were emitting lower frequencies
hot spots
location where hot molten rock rises through tectonic plates
Lithosphere
made of crust and upper part of mantle; broken into tectonic plates
Asthenosphere characteristics
made of hot mantle, flows, solid
fourth piece of wegeners evidence
matching geological units and mountain belts
Seafloor Spreading Theory
mechanism by which new oceanic crust is formed and destroyed
charcteristics of the core
most dense layer
How does seafloor spreading work?
new ocean crust forms at MORs, from rising magma - causes seafloor to spread/ move away from mor on both directions - old crust is destroyed at trenches where it sinks back down into mantle
continental-continental
no subduction, volcanoes or trench - crust compresses and thickens - forms mountains
what drives plate motion?
originally, hypothesized convection, not quite right
What part of the core is liquid?
outer core
Where are Jovian planets located?
outer solar system
what part of the disk is filled with ice
outside
what kind of rock is mantle?
peridotite rock
plates
pieces of the lithosphere
asthenosphere
plastic, weak, ductile layer of earth
What happens when dying stars explode?
produce even heavier elements such as elements greater than iron
Theory of Plate Tectonics
the outer layer of the earth is broken into separate plates that move around w/ respect to one another
Whats at the center of the solar system?
the sun
Big Bang Theory
the universe began by exploding all of energy and matter packed into a single point
ocean crust
thick basalt
Crust characteristics
thin and has lighter elements
continental crust
thin and less dense
what controls how high or low an object floats
to float an object needs to be less dense - its thickness - its density
continental lithosphere
topped by continental crust, thicker and less dense than oceanic lithosphere