REVIEW DECK Flashcards
crystalline structure
atoms in a mineral must occupy fixed positions in a grid called a lattice
mineral def
nat occurring
solid
inorganic
defineable chem comp
orderly arrangement or molecules in a lattice
crystal growth
growth occurs as atoms attach to the outer surface
in an open cavity crystal faces grow perfectly
early crystals act as seeds for further growth
three types of crystals (based on face visibility
anhedral
euhedral
subhedral
mineral identitification characteristics
color
streak
luster
hardness
spec grav
cry habit
cleavage
reaction to acid
special prop
7 classes + 5 subgroups of #7
sulfides
oxides
sulfates
carbonates
halides
native metals
silica
- independant tetra
-single chain
-double chain
-sheet silicates
-framework silicates
clay minerals are a type of
sheet silicates
two types of clays
koalinite and smectite
does koalinite swell
no
does smectite swell
yes
what kind of clay swells and why
smectite
TOT structure allows water to enter
how small is clay
<4 microns
salt use
tatsty
5 ways minerals form
precipitation in water
solidification from a melt
solid state diffusion
biomineralization
precipitation from gas
solid state diffusion def
atom by atom transfer without ever melting
rock def
a coherent naturally occurring solid aggregate of minerals or less commonly a body of glass
two main types of rocks
clastic
crystal
bedrock vs clast def
bedrock attached to ground
clast not
physical characteristics that identify rocks
layering
grain size
texture
equantnness
three textures + secret fourth
crystalline
fragmental
glassy
foliated
not sedimentary to sedimentary
erosion transportation deposition
sedimentary to sedimentary
erosion transportation
redeposition
meta to ignous
melting
meta to meta
burial heating and remetamorphism
sed to meta
burial and heating
igenous to igneous
heating and remelting
sed to igneous
heating and melting
crust to rock
input of new melt into the crust from the mantle
rock to crust
subduction
three main types of rocks by orginin
igneous
sedimentary
metamorphic
two igenous realms
extrusive
intrusive
what is a melt
molten rock
lava vs magma
lava extrusive
magma intrusive
the crust and athenosphere are mostly
solid rock
melts occur in
localized areas
3 reasons for melting
decompression
flux (volatiles
heat transfer
how decompression melts
temp constant pressure goes down
melts the rock
how introduction of volatiles melts
subduction introduces volatiles
(water) changes the melting point
felsic %
67-76
intermediate %
53-66%
mafic %
46-52%
ultramafic %
38-45
felsic flow is _____ viscous because of the
more viscous
because of the silica
mafic flow is ______ viscous because of the
less viscous
because less silica
how does a melt become a rock (how does it freeze)
volatiles leave
reaches the surface
temp or pressure change
types of intrusions
(which is parallel)
dike (perpendicular)
sills (parallel)
what is a pluton
a magma chamber that solidified
what is a batholith
a bunch of plutons together
how does partial melting and crystal refractionalizatoion work
rock begins to melt
felsic melts earlier
resulting magma is more felsic
as mafic rocks stay solid, the felsic minerals migrate away
when it cools the opposite happens the mafic rocks solidify first
the whole mantle is one type of rock (what is it)
peroditite
aphanitic def
fine grained, cooled fast, crystals couldn’t grow much
phaneritic def
coarse grained, cooled slow, crystals grew more
porphyritic def
two cooling stages, slow to fast
aphanitic probably cooled where
underground
phaneritic probably cooled where
above ground
felsic rocks have what color
light
mafic rocks have what color
dark
is pumice mafic
NAH
3 types of volcano
shield
stratovolcano
cinder cones
do shield volcanoes have mafic lava
YEE
mafic rocks are rich in
iron and magnesium
andesitic lava does what
bubbles up a little and fractures
rhyolitic lava does what
super viscous
doesn’t move much
super felsic
parts of a volcani
magma chamber
fissures and vents
craters
calderas
lava tubes
………
do the biggest volcanoes have felsic lava
no
how do calderas form
the side of the volcanoes collapse into the crater
effusive eruption
low viscosity
lava fountains and flows easily
phreatic eruption
groundwater interacts with magma making a steam explosion
plinean / explosive
poof vesuvius felsic explosion
two umbrella types of weathering
physical
chemical
5 types of chemical weathering
dissolutionh
hydrolysis
oxidation
hydration
organic influence
physical and chemical weather happen
together
the least stable minerals weather the
fastest
what is wethering
combination of phys and chem processes that turn rock in debris or ditritus also they corrode
mafic minerals weather by
oxidation
felsic minerals weather by
hyrodlosis
soil def
sediment that has been modified by physical and chemical interaction with organic material and rainwater
how is soil destroyed
nutrient removal
soil erosion
how does nutrient removal happen
farming crops takes away minerals
how does soil erosion happen
you clear cut the woods and water and wind destroys it super quick
four types of sed rocks
clastic
biochemical
organic
chemical
how does clastic rocks form
weathering
erosion
transportation
deposition
lithification (two steps)
two steps of lithification
compaction
cementataion
ways to classify sedimentary rocks
grain size
composition
angularity
sorting
grain vs clast support
maturity
maturity is a combination of ____ and tells you generally how far
grain size
composition
angularity
sorting
grain vs clast
support
how far away rock has been transported
sediment grain sizes in mm
boulder >256
cobbles 65-256
pebbles 3-64
sand 1/16-2
silt 1/256-1/16
mud <1/256
common types of sedimentary
breccia and conglomorate
sandstone
must one
limestone
chert
evaporites
symmetric ripple marks
beach
assymetric ripple marks
river
what is diagenesis
all physica chemical and biological processes that urn sediments into sedimentary rocks
<300C
what is a metamorphic rock
underwent solid state alteration of pre existing rocks
metamorphism is caused at what temps
250-850 C
different rocks melt at different temps
what is a protolith
the parent rock that turned into a specific metamorphic rock
effects of metamorphism
texture change
foliation
minerology
(new minerals can form through solid state diffusion)
shale is the protolith of
slate
schist
gneiss
migmatite
4 metamorphic processes
recrystallization
neocrystalization
pressure solution
plastic deformation
recrystalization def
crystals change size
neocrystalization def
crystals change comp
pressure solution def
minerals grains partially dissolve where open surfaces press together
plastic deformation def
minerals softener and deform under intend P and T
polymorphs are
different rocks that can form from the same protolith
differential pressure causes
inequant grains
types of metamorphic rocks
foliated
non foliated
metamorphic grade def
change from protolith
types of metmorphism
thermal
burial
regional
thermal metamorphism def
heating by a plutonic intrusion
burial metamorphism def
deep burial in a basin diagenesis that went a bit too far
regional metamorphism happens in
mountain building events
orogenesis refers to
regional metamorphism
wegner’s evidence for continental drift
glacial striations
climate belts
fossils
mountain changes and formations
what was Wegner missing
how did the continents move through rocks
why did the move
new evidence for continental drift
sonar
radar
……
hess’s method for plate movement
oceanic plate descending into mantle is how rock is destroyed
super proof for continental drift
magnetic inclination and declination leaves a signature of location and paleopole at time when rock solidifes
magnetic anomalies why
pole swaps, magnetic materials pointed towards the poles, but when they were swapped they went the other way, when you measure their magnetism they cancel out in bands
in negative anomalies the magnetic pole was
in the south
how many major plates
12
how many total plates
20
plate tectonics vs continental drift
plate tectonics has the “why”
that continental drift didn’t have
lithosphere thickness under continents
150-200km
lithosphere thickness under oceans
10-100km
lithosphere is the
cryst and ridgid mantle
athenosphere is the
mantle minus lithosphere
(plastic mantle)
continental crust thickness
25-70 km
oceanic crust thickness
7-10km
the ocean that is not on oceanic crust is on the
continental rift
the continental rift is on what kind of crust
continental
the abyssal plain is
ocean not on continental crust (on oceanic crust)
plate boundary types
divergent
convergent
transform
an active continental boundary is on a
plate boundary
a passive continental boundary is
not on a plate boundary
what drives plate movement
convection
plate velocity
1-15cm / year
plates move at about the same speed that
your fingernails grow
p waves travel ____ s waves
faster than
how did scientists find the size of the layers of the earth
shadow zones and refraction
p wave shadow zones
103-143 degrees
which waves travel through liquid
P waves
s wave shadow zones
greater than 103 degrees