geosphere test 3 Flashcards
what does chemical weathering involve
chemical change
what does chemical change involve
chemical reactions
what are chemical reactions represented by
chemical equations
chemical equations use _____ and ______ to represent chemical reactions
symbols and formulas
AB —>
A + B
A + B —>
AB
A + B —>
AB + Heat
what type is A+B —> AB + Heat
exothermic
what does exothermic mean
gives off energy, gets hotter as it reacts, makes heat
A + B + heat —>
AB
what type of energy is A + B + heat —> AB
endothermic
endothermic
requires the input of energy; gets colder as it reacts; uses heat
A+B —> AB (combined as one)
synthesis
AB —> A+B (takes 2 things and breaks it down into individual pieces)
decomposition
AB + C —> CB + A (a substance displaces another substance)
single displacement
AB + CD —> AD + CB (two shapes being displaced)
double displacement
burning fuels is a reaction; releases carbon dioxide and water; both are greenhouse gases
combustion reaction
matter is neither created nor destroyed. it is converted to other forms. (the reason we balance equations)
law of conservation of matter
what is the bridge between biology (life) and rock (geology)
soil
what components make up soil
minerals (from weathering of rocks), organic matter (humus, dead animal or plant matter) , water (moisture), air
what controls formation of soil
parent material, climate, plants and animals, slope, time
bedrock determines chemistry of soil (not weathered rock); most important thing to control formation
parent material
wet climate and temperature extreme/rapid fluctuate cold- cold to hot (rapid changes and can impact soil)
climate
increase aeration (worms), water, and fertilizer; animals can fertilize soil
plants and animals
steep slope =
thin soil
flat slope =
thicker soil
types of slopes
steep and flat
orientation of slope
north or south
north orientation
cooler and wetter
south orientation
hotter and drier
you need a long time for soils to form
time
soil profiles
O
A
B
C
R
soil profile - O
humus layer (organic)
soil profile- A
topsoil
soil profile- B
subsoil (zone of accumulation)
soil profile- C
weathered rock
soil profile- R
bedrock
soil profile
organic (humus), topsoil, subsoil, weathered rock, bedrock
what happens in the organic layer
horizon, leaf litter, organic material
what happens in the topsoil
horizon, plough zone, rich in organic matter
what happens in weathered rock
horizon, weathering soil; little organic material of life
what happens in bedrock
horizon; unweathered parent material
how do soils differ
texture, color, mineral content
how do soils happens
weathering and eroding
break down of rocks into smaller pieces
weathering
transport the rock material through wind, water and ice
erosion
what are the types of weathering
mechanical and chemical
disintegration and physical changes
mechanical weathering
decomposition; chemical changes
chemical weathering
types of mechanical weathering
frost wedging, exfoliation, biological activity
types of chemical weathering
carbonic acid, oxidation, hydrolysis
water expands 9% upon freezing
frost wedging
“sheeting”; occurs when pressure from overlying rocks released; exfoliation domes (half domes, stone mountain)
exfoliation (unloading)
tree roots grown in joints in rocks; roots wedge apart joints and lift up rock, allow water to seep into joints; commonly seen in town sidewalks
biological activity
what is an example of chemical weathering
cleopatras needle
carbon dioxide + water = carbonic acid
CO2 + H2) = H2CO3 +
what minerals are in carbonic acid weathering
calcite
what rocks are in carbonic acid weathering
limestone and marble
what minerals are in oxidation
magnetite, hematite
what rocks are in oxidation
any containing fe or copper
breaking apart due to water
hydrolysis
what minerals are in hydrolysis
kaolinite, clay minerals
what rocks are in hydrolysis
granites, siltstones, claystones
what happens with hydrolysis
shrinking, swelling
what does kaolinite and water make
clay
the squeezing of sediments by the weight of the rocks and sediments above them
compaction
process by which clastic sediments become lithified or consolidated into hard, compact rocks, usually through a deposition or precipitation of minerals in the spaces among the individual grains of sediment; cement from fluids bind sediments together
cementation
processes of converting sediment into sedimentary rock through compaction and cementation. most important cements in sedimentary rocks: calcite, silica, iron- oxides
lithification
made up of pieces or pre exisiting rocks. pieces of rock are loosened by weathering, then transported to some basin or depression where sediment is trapped. if the sediment is buried deeply, it becomes compacted and cemented, forming sedimentary rock
clastic
what are the two types of sedimentary rocks
clastic and nonclastic
biological or chemical- from when large numbers of living things die. this is one of the ways limestone can form. ocean dwelling organisms such as oysters, clams, mussels and coral use calcium carbonate found in seawater to create their shells and bones. as these organisms die, their shells and bones are broken down by waves and settle on the ocean floor where they are compacted over millions of years, creating limestone from the sediments and the pressure of the ocean water
nonclastic
which rocks are clastic
conglomerate, sandstone, shale
which rocks are nonclastic chemical
rock salt, gypsum, limestone
which rocks are nonclastic biological
limestone, coal
sediments are defined by what
the size of their fragments
what is the largest to smallest sediments
boulders, cobbles, pebbles, sand, silt, clay
how can you tell the relative age of rocks
by its position in undisturbed rocks; oldest is at the bottom, youngest at top
what is the law that tells you the relative age of rocks
aka law of superposition
which way are sediments layered
sediments are deposited horizontally
what happens if the rocks are tilted
tectonic pressure has moved
what do layers indicate about rocks
different layers of rock mean different types of sediments have been washed into the area
what do thick layers of rock imply
a lot of sediment at once (storm or flood) or a long time of deposition
how is conglomerate rock formed
river system closer to source
how is sandstone formed
desert, beach, river sandbars
how is shale/mudstone formed
river delta, floodplain
how is coal formed
swamps
how is limestone formed
shallow, warm oceans, reef or bay
do all rocks weather at the same time
no, sediments are held together by various types of cement
what is the key to metamorphism
heat, pressure, hydrothermal liquids
magma, impacts
heat
plate tectonics
pressure
extremely hot water
hydrothermal liquids
what happens in metamorphic rock
the molecules in a metamorphic rock never get to the slide point. they break and restructure new bonds
breaking and restructuring of bonds in a metamorphic rock is known as
recrystallization
this is key to metamorphism
recrystallization
two classifications of metamorphic rock
foliated and texture
rocks form in layers, form perpendicular to pressure
foliated
coarse or fine, higher temperature means larger crystals
texture
how is gneiss made
it starts as sediment (mud) then forms into shale from the pressure of overlying rock, then forms into slate from heat and pressure from tectonics, then turns into phyllite as more heat is applied. more heat gets applied and it turns into schist, and even more heat is applied and it turns into gneiss
if the original rock is limestone then the metamorphic rock is ….
marble
if the original rock is granite then the metamorphic rock is
gneiss
if the original rock is coal then the metamorphic rock is
anthracite
if the original rock is shale then the metamorphic rock is
slate
if the original rock is basalt then the metamorphic rock is
greenstone
if the original rock is sandstone then the metamorphic rock is
quartzite
cooled molten material
igneous rocks
melting of rocks
igneous
transfer of heat energy to rock, motion of atoms increase, atoms begin to move further apart, exceed attractive forces, atoms slide past each other (becomes a liquid)
melting of rocks
the rock heats up, kinetic energy increases and starts moving more
magma
if you take a rock and melt it, its _____. when it comes out of the earth, its ______
magma; lava
how do you classify igneous rocks
based on volcanic origin
if the rock is made from lava it is
extrusive
if the rock is formed from magma it is
intrusive
as magma cools, minerals arrange themselves in an orderly fashion
texture
size of mineral crystals is determined by
cooling rate
small crystals =
fast cool
large crystals =
slow cool
coarse texture means
it is intrusive, its origin is at depth, it has a slow cooling rate, and it was formed from magma (plutonic)
fine texture means
it is extrusive, its origin is at or near the surface, it is fast cooling, and it was formed from lava (volcanic)
glassy texture means
extrusive, on surface, very fast cooling, lava (volcanic)
if it has a light shade, it is what colors
pink, whites, light greys
if it has a light shade, it has what type of mineral composition
felsic (quartz, feldspars) (has continental crust)
if it a medium shade, it has what type of colors
medium greys
if it is medium shade, it has what type of mineral composition
andesitic mixture (mixture of felsic and mafic)
if it has a dark shade, it has what colors
blacks, dark browns, deep reds
if it is a dark shade, what type of mineral composition does it have
mafic (iron and magnesium) (have to have ocean continental convergence)
where do minerals cool?
in the magma chamber (bowens reaction series)
talks about temperature in the magma chamber- must understand how it is cooling
bowens reaction series
dark rocks form at what temperatures
high temperatures
what is the last mineral to form
quartz
which rock is fine grained and light shade
rhyolite
which rock is fine grained and medium shade
andesite
which rock is fine grained and dark shade?
basalt
which rock is coarse grained and light shade
granite
which rock is coarse grained and medium shade
diorite
which rock is coarse grained and dark shade
gabbro
which rock is pyroclastic and light shade
pumice
which rock is pyroclastic and medium shade
scoria
which rock is pyroclastic and dark shade
obsidian
cenozoic
recent animls, age of mammals
mesozoic
middle animals; age of dinosaurs
paleozoic
old animals; age of insects and fishes
precambrian
informal time name prior to palezoic
what happened after the mesozoic era
no more dinosaurs
phanerozoic eon
544 mya to present
cenozoic era
65 mya to present
mesozoic era
245 to 65 mya
paleozoic era
544 mya to 245 mya
precambrian time
4500 mya to 544 mya
proterozoic era
2500 to 544 mya
archaen
3800 to 2500 mya
hadean
4500 to 3800 mya
when did pangea happen
300 million years ago
when did rodinia happen
1.25 billion years ago
kenorland
2.5 bya
Ur
3 bya
