sedimentary
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- Created by: millmcgread
- Created on: 25-04-23 17:10
formation of sediment
most rocks form underground, when they are uplifted and they reach the surface, the change in conditions causes rocks to weaken and weather
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weathering
the breakdown of rocks in situ
( the chemical alteration and mechanical breakdown of rocks by exposure to the atmosphere, water and organic matter
( the chemical alteration and mechanical breakdown of rocks by exposure to the atmosphere, water and organic matter
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3 categories of weathering
- chemical
- mechanical/ physical
- biological
- mechanical/ physical
- biological
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chemical weathering
breaks the actual structure of the minerals down - helps to decompose rock
all examples of weathering involve water, and they produce ions which get removed in solution leaving an insoluble residue
all examples of weathering involve water, and they produce ions which get removed in solution leaving an insoluble residue
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carbonation
- when CO2 in the atmosphere reacts with water and soil pore water to form carbonic acid.
- this acid breaks down the rocks
- limestone
- this acid breaks down the rocks
- limestone
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hydrolysis
- reaction between water and silicate minerals to break them down, it can be sped up if the water contains carbonic acid.
- the hydrogen ions from the water react with the minerals' ions.
- the hydrogen ions from the water react with the minerals' ions.
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mechanical weathering
( exfoliation)
( exfoliation)
"onion skin weathering"
- when a certain environment has a large diurnal range, it causes the different minerals in a rock to expand and cool repeatedly by different amounts
- this weakens the rock and causes curved surfaces to peel off from it
- when a certain environment has a large diurnal range, it causes the different minerals in a rock to expand and cool repeatedly by different amounts
- this weakens the rock and causes curved surfaces to peel off from it
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frost shattering
- occurs in environments where the temperature fluctuates above and below freezing. above freezing, water naturally enters the rock.
- then when it freezes, the water in the cracks expands by 9%
- this exerts pressure on the rock and eventually causes it
- then when it freezes, the water in the cracks expands by 9%
- this exerts pressure on the rock and eventually causes it
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pressure release
- rocks underground, even if they are shallow, are at much greater pressure then at the surface
- when the rock above them is eroded, this pressure is released
- this causes the rock to expand and produce fractures
- when the rock above them is eroded, this pressure is released
- this causes the rock to expand and produce fractures
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biological weathering
(root action)
(root action)
- tree roots can grow along bedding plans etc and force layers of the rock apart
- by doing so, they also keep these surfaces open so water can enter and weather them chemically
- by doing so, they also keep these surfaces open so water can enter and weather them chemically
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burrowing
- when animals burrow it can break rock apart, and it also brings rocks up to the surface which allows it to be weathered even further.
burrows allow gases and water to enter rocks too, promoting chemical weathering
burrows allow gases and water to enter rocks too, promoting chemical weathering
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transport
due to gravity, wind, rivers/sea and ice
- as they are transported, grains of sediments are subject to erosion
This can be by attrition or abrasion
- as they are transported, grains of sediments are subject to erosion
This can be by attrition or abrasion
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attrition
wearing away of grains due to collisions with other grains
hard minerals (eg quartz) are more resistant to erosion
hard minerals (eg quartz) are more resistant to erosion
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abrasion
wearing away of the Earth's surface by the action of dragging sediment over it
hard minerals (eg quartz) are more resistant to erosion
hard minerals (eg quartz) are more resistant to erosion
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mineralogical maturity
a measure of the extent to which minerals have been destroyed by weathering and erosion
The most mineralogically mature sediment will only contain Quartz, all the weaker ones have been eroded away
The most mineralogically mature sediment will only contain Quartz, all the weaker ones have been eroded away
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methods of transport
suspended load - suspension,
bed load - saltation, traction
solution - dissolved in the water
bed load - saltation, traction
solution - dissolved in the water
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grain shape, roundness and size
grains get rounder the longer they have been transported for
we can look at shape through its sphericity
we can look at shape through its sphericity
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wentworth-udden scale
>2mm = gravel, pebbles, cobbles, boulders (RUDACEOUS)- breccia & conglomerate
2-0.0625mm = sand (ARENACEOUS)- arkose, greywacke, DS
<0.0625mm = silt/clay (ARGILLACEOUS)
2-0.0625mm = sand (ARENACEOUS)- arkose, greywacke, DS
<0.0625mm = silt/clay (ARGILLACEOUS)
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textural maturity
is a measure of the extent to which a sediment is well sorted and well rounded
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sorting
the degree to which particles are the same size
If all grains are the same size = well sorted
if they are a wide range of sizes = poorly sorted
If all grains are the same size = well sorted
if they are a wide range of sizes = poorly sorted
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sorting explained
can tell us about the environment of deposition
- poorly sorted usually hasn't been transported far and the transporting medium must have lost energy quickly to just deposit them this way
if energy was lost gradually, coarsest sediment would have been d
- poorly sorted usually hasn't been transported far and the transporting medium must have lost energy quickly to just deposit them this way
if energy was lost gradually, coarsest sediment would have been d
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calculate sorting
PAG (1)
PAG (1)
-using a sieve bank
arranged so biggest holes are at the top and smallest at the bottom
-a known amount of sediment is poured into the top and its shaken for a set time, during this the sediment will filter through and accumulate in the sieve that it can
arranged so biggest holes are at the top and smallest at the bottom
-a known amount of sediment is poured into the top and its shaken for a set time, during this the sediment will filter through and accumulate in the sieve that it can
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calculate sorting
PAG (2)
PAG (2)
- we can then measure how much sediment is in each one
- our results can be plotted as a histogram or cumulative frequency graph
- we can also calculate the coefficient of sorting from this
- our results can be plotted as a histogram or cumulative frequency graph
- we can also calculate the coefficient of sorting from this
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rudaceous products
- are simplified on whether the clasts are rounded or not
- breccia - angular, no transported for as long, grains often mixed with finer grains and set in a matrix
- conglomerates- rounded clasts, been transported for longer, may also be poorly sorted, h
- breccia - angular, no transported for as long, grains often mixed with finer grains and set in a matrix
- conglomerates- rounded clasts, been transported for longer, may also be poorly sorted, h
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sandtones - arenecous products
- Orthoquartzite
- Orthoquartzite
ONLY quartz, held together by a quartz cement
>90% quartz
- white grey in colour
- grains are well sorted and well rounded, indicating extensive transport and weathering
- mineralogically and texturally mature
- form in shallow marine deposits
>90% quartz
- white grey in colour
- grains are well sorted and well rounded, indicating extensive transport and weathering
- mineralogically and texturally mature
- form in shallow marine deposits
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Desert sandstone
- red due to iron oxide coating the grains
- well sorted and rounded, high sphericity
- grains appear frosted
- cement made of silica/ iron
- form in arid environments
- well sorted and rounded, high sphericity
- grains appear frosted
- cement made of silica/ iron
- form in arid environments
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arkose
- contains at least 25% feldspar, makes it pink in colour
- other main mineral is quartz, also has rock fragments and mica
- moderately sorted - not transported for as long
- forms in alluvial fan environments and arid areas
- other main mineral is quartz, also has rock fragments and mica
- moderately sorted - not transported for as long
- forms in alluvial fan environments and arid areas
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greywacke
- dark coloured and poorly sorted rock, with angular clasts.
- mainly consist of rock fragments, with some quartz and K feldspar
>15% of the rock is clay matrix.
- from as turbidite deposits so often contain graded bedding
- mainly consist of rock fragments, with some quartz and K feldspar
>15% of the rock is clay matrix.
- from as turbidite deposits so often contain graded bedding
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argillaceous products
- clay
- clay
- mainly contains clay minerals and has a variety of colours depending on its carbon and iron content
- it is plastic so can be moulded and it forms layers (not visible)
- it is plastic so can be moulded and it forms layers (not visible)
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mudstone
- dark grey
- contain clay minerals, mica, quartz, but you can't identify minerals
- no layering and no plasticity
- contain clay minerals, mica, quartz, but you can't identify minerals
- no layering and no plasticity
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shale
- dark coloured with distinctive layers due to the alignment of clay minerals.
- the rock easily splits along these layers, so it is fissile
- contains clay minerals, mica, quartz
- brittle and hard
- the rock easily splits along these layers, so it is fissile
- contains clay minerals, mica, quartz
- brittle and hard
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classification of carbonate rocks
- any sedimentary rocks containing a high percentage of calcite or dolomite
- any rock containing over 50% CaCO3 is a limestone, but most contain >90%
- Either form chemically or biologically
- any rock containing over 50% CaCO3 is a limestone, but most contain >90%
- Either form chemically or biologically
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oolitic limestone
- chemically
- chemically
- chemically formed limestones containing oolithis
- these are spherical grains which show concentric banding of carbonate material
- form where sea water contains a lot of calcite
- they accumulate on the sea bed &start to layer, become buried to set the
- these are spherical grains which show concentric banding of carbonate material
- form where sea water contains a lot of calcite
- they accumulate on the sea bed &start to layer, become buried to set the
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fossilliferous limestone
- biological fossils
- biological fossils
- biologically formed limestone containing fossils, may have micrite or sparite
- form in a range of environments from low energy freshwater lakes to marine
- the more broken fossils = higher the energy
- eg crionoidal limestone
- form in a range of environments from low energy freshwater lakes to marine
- the more broken fossils = higher the energy
- eg crionoidal limestone
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chalk
- biological coccoliths
- biological coccoliths
- biologically formed limestones composed of coccolithophores which are calcereous disks that form the skeletons of algae
- forms in low energy, deep water environments
- forms in low energy, deep water environments
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diagenesis
- all of the changes that take place in sediments at low temperature and pressure, at or near the earths surface
- cementation and compaction
- sediments become lithified
- cementation and compaction
- sediments become lithified
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lithification
- the process of changing of unconsolidated sediment into rock
- lithification is a part of diagenesis
- lithification is a part of diagenesis
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compaction
as layers of sediment accumulate, it increases the vertical pressure, so it compacts the sediments underneath
- processes such as pressure dissolution and crystallisation occur
- processes such as pressure dissolution and crystallisation occur
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pressure dissolution
when minerals dissolve as the result of applied pressure, grains get closer together which reduces porosity
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mud and sand
muds/clays are much more affected then sandstones. the original thickness of mud can reduce by up to 80% when its lithified
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plants and coals
when plant remains fall into swamps, decay uses up available oxygen. Anaerobic bacteria change the plant material into peat. If this is then buried and put under increased pressure and temperature, it begins to take on the properties of coal as volatiles
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sandstones
- cementation
- cementation
sands are more permeable than muds, groundwater which contains minerals in solution flows through pore spaces and can precipitate minerals out, forming a cement
- reduces pore spaces
- reduces pore spaces
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limestones
-cementation
-cementation
modern limestones are made of unstable aragonite which changes to calcite over time
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facies and uniformitarianism
- facies includes all of the characteristics of a sedimentary rock that are produced by its environment of deposition and allow it to be distinguished from rock deposited in an adjacent environment
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facies and uniformitarianism 2
- includes, mineral content, grain size, and sorting, structures, fossil content
- physical characteristics of a rock such as mineral content are used to describe lithofacies
- fossil content defines biofaces
- facies associations are a group of sedimen
- physical characteristics of a rock such as mineral content are used to describe lithofacies
- fossil content defines biofaces
- facies associations are a group of sedimen
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facies and uniformitarianism 3
most facies associations imply the process imply the process that produced the rock in its environment
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sediment transport facies
- we would expect sediments to be the same lithology of the rocks at their source
- conglomerates containing clasts from a mixture of lithologies from their source area are polymitic
- conglomerates containing clasts from a mixture of lithologies from their source area are polymitic
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ogliomitic
conglomerates are made up of a few different lithologies
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monomitic
conglomerates are made up of only on type
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rivers
- sorting by size is the more important process
- coarsest usually deposited near the source and it gets progressively finer
- coarsest usually deposited near the source and it gets progressively finer
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wind
- sediments have a small size range
- wind transports fine material (only sand and silt)
- texturally and mineralogically mature
- wind transports fine material (only sand and silt)
- texturally and mineralogically mature
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glacial
- weathering is more important
- sediment is often poorly sorted
- often transported for short distances
- sediment deposited by glaciers are called till and become tillites when lithified
- fluvio-glacial deposits
- sediment is often poorly sorted
- often transported for short distances
- sediment deposited by glaciers are called till and become tillites when lithified
- fluvio-glacial deposits
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shallow marine
- deposition occurs in the littoral zone
- sorting by size is the opposite, coarser grains are transported further
- weathering is important as grains have to withstand high energy waves
- sorting by size is the opposite, coarser grains are transported further
- weathering is important as grains have to withstand high energy waves
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sedimentary structures
- they are palaeo environmental indicators
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cross bedding
- palaeo current indicator
- way up indicator
- palaeo current indicator
- way up indicator
- sand dunes get deposited by a uni-directional current to form dunes
- the sand grains continually build up on the stoss side until they avalanche down the lee side
- settle at a maximum angle of 37
- this preserves the lee side
- process repeats
- the sand grains continually build up on the stoss side until they avalanche down the lee side
- settle at a maximum angle of 37
- this preserves the lee side
- process repeats
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ripple marks
- form when sand grains are transported in high energy conditions
- symmetrical - formed by oscillating currents, common on beaches
- asymmetrical ripple marks - formed by uni-directional flow, so are common in rivers, shallow seas and deserts
- symmetrical - formed by oscillating currents, common on beaches
- asymmetrical ripple marks - formed by uni-directional flow, so are common in rivers, shallow seas and deserts
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graded bedding
- where the largest particles are deposited first and are at the bottom and finer particles on top
- good way up indicator
- forms when energy levels drop gradually and sediment begins to settle out of suspension
- good way up indicator
- forms when energy levels drop gradually and sediment begins to settle out of suspension
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desiccation cracks
- form in clay rich sediment
- form in areas with high evaporation rates, water from the sediment is lost by evaporation and it causes the mud to contract and crack
- forms polygonal shaped blocks
- good way- up indicators
- good palaeo environmental i
- form in areas with high evaporation rates, water from the sediment is lost by evaporation and it causes the mud to contract and crack
- forms polygonal shaped blocks
- good way- up indicators
- good palaeo environmental i
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salt pseudomorphs
-often from in playa lakes, desert environment
- cubic halite crystals grow at the surface of a bed when salty water is evaporated
- when the lake refills, the salt crystals get dissolved, leaving behind these cubic moulds
-then get infilled by sedimen
- cubic halite crystals grow at the surface of a bed when salty water is evaporated
- when the lake refills, the salt crystals get dissolved, leaving behind these cubic moulds
-then get infilled by sedimen
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imbricate structure
- pebbles are rolled along a river bed and then pile up against one another
- flat pebbles stack against each other so their long axes are roughly parallel
- this orientation occurs because it provides the maximum resistance to movement
- flat pebbles stack against each other so their long axes are roughly parallel
- this orientation occurs because it provides the maximum resistance to movement
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imbricate structure 2
- the pebbles are inclined in an upstream direction, with the top of the pebbles pointing downstream
- however, in a density flow, the long axes will point downstream instead
- however, in a density flow, the long axes will point downstream instead
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flute clasts
- form at the base of beds as a result of erosion caused by turbulent flow
- they form parallel to the current flow
- they are deeper and pointed at the upstream end
- they are preserved if they are infilled with sediment
- good palaeocurrent indicators
- they form parallel to the current flow
- they are deeper and pointed at the upstream end
- they are preserved if they are infilled with sediment
- good palaeocurrent indicators
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deposition in fluvial environments
- rivers
- high energy environment with a uni-directional current
- heavy rainfall causes energy to increase - small streams carry boulders
- velocity of water is slower near the sides
- deposition occurs when the velocity is reduced
- high energy environment with a uni-directional current
- heavy rainfall causes energy to increase - small streams carry boulders
- velocity of water is slower near the sides
- deposition occurs when the velocity is reduced
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fluvial environment products
- alluvial fan breccias and conglomerates
- channel conglomerates and sandstones
- flood plain clays and silts
- channel conglomerates and sandstones
- flood plain clays and silts
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alluvial fan breccias and conglomerates
- when mountain streams flow into flat valleys, the decrease in energy causes sediment to be deposited as alluvial fans
- breccias formed by scree or debris flow
- conglomerates are deposited in the streams
- breccias formed by scree or debris flow
- conglomerates are deposited in the streams
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channel conglomerates and sandstones
the outside banks of meander bends are eroded and deposition occurs on the inside of a point bar
- form micaceous sandstones which may show cross bedding
- form micaceous sandstones which may show cross bedding
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flood plain clays and silts
- in times of high flow, rivers flood the area adjacent to the channel and form flood plains
- clays and silts are deposited
- they may show small scale cross bedding or evidence of exposure to the elements eg desiccation cracks
- clays and silts are deposited
- they may show small scale cross bedding or evidence of exposure to the elements eg desiccation cracks
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deposition in hot desert environments
- have a large diurnal temperature range
- when rainfall does occur, it is torrential, and the bare, dry ground allows for rapid run-off, this causes flash floods
- water is one of the main agents of erosion and transportation in deserts
- gradual affec
- when rainfall does occur, it is torrential, and the bare, dry ground allows for rapid run-off, this causes flash floods
- water is one of the main agents of erosion and transportation in deserts
- gradual affec
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wadi conglomerates
- desert stream channels are wadis
- when the flash foods are over they lose energy quickly, therefore deposition is rapid, and leaves poorly sorted conglomerates
- grains may be red due to iron oxidation
- when the flash foods are over they lose energy quickly, therefore deposition is rapid, and leaves poorly sorted conglomerates
- grains may be red due to iron oxidation
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alluvial fan arkose
- after a flash flood, the coarse grained sediments deposited closer to the mountains are typically breccias
- after this, an alluvial fan arkose form
- after this, an alluvial fan arkose form
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aeolian sandstones
- sand grains are transported by high energy winds in the desert, so get eroded lots
- well rounded and sorted, spherical and frosted
- shows cross bedding
- well rounded and sorted, spherical and frosted
- shows cross bedding
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playa lake evaporites
- desert streams do not flow all the way to the sea
- they dry up too much and rainfall is too infrequent
- they drain into playa lakes
- water contains lots of minerals in solution so when they evaporate the ions become more concentrated
- they dry up too much and rainfall is too infrequent
- they drain into playa lakes
- water contains lots of minerals in solution so when they evaporate the ions become more concentrated
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deposition in shallow siliciclastic environments
- sandy, clastic seas
- most of the sediment here has been transported by rivers
- two main sections - littoral zone/ beaches and the shallow seas
"shallow seas" starts from waters edge and goes to the start of the continental.
- most of the sediment here has been transported by rivers
- two main sections - littoral zone/ beaches and the shallow seas
"shallow seas" starts from waters edge and goes to the start of the continental.
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beach environments
- main well sorted and well rounded sand and gravel as its constantly being moved
- commonly forms orthoquartzite
- symmetrical ripple marks due to bi-directional movement
- conglomerates usually contain shell fragments
- commonly forms orthoquartzite
- symmetrical ripple marks due to bi-directional movement
- conglomerates usually contain shell fragments
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shallow seas
- sediment size decreases as depth and distance away from coast increases
- asymmetrical ripple marks form
- sandstones that form contain glauconite
- mudstones/clays form as energy decreases
- asymmetrical ripple marks form
- sandstones that form contain glauconite
- mudstones/clays form as energy decreases
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deposition in carbonate environments
- seas with muds on the floor
- limestones form instead
- limestones form instead
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shallow carbonate seas
- biologically and chemically formed limestones form here
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fossiliferous limestone
- made up of 75% fossils, and the rest is mud
- commonly grey, hard, well jointed
- commonly grey, hard, well jointed
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reef limestones
- algae which secretes calcium carbonate encrust reefs and cement it together
- typically no beds
- can be environmental indicators as reefs require certain conditions
- in the pacific volcanic islands get surrounded by corals & as they sink they grow t
- typically no beds
- can be environmental indicators as reefs require certain conditions
- in the pacific volcanic islands get surrounded by corals & as they sink they grow t
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oolitic limestones
- form from ooliths
- typically white crossed bedded
- form from chemical processes in warm tropical climates in water <2m deep
- fossils are common but often broken due high energy
- typically white crossed bedded
- form from chemical processes in warm tropical climates in water <2m deep
- fossils are common but often broken due high energy
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deep water carbonate seas
deep water is typically lower energy
- here carbonates are only preserved when the sea floor is above the carbonate compensation depth
- here carbonates are only preserved when the sea floor is above the carbonate compensation depth
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the carbonate compensation depth
the depth at which the rate of solution equals/ exceeds the rate of supply of skeletal remains
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chalk
white, hard, massive, well joined and biologically formed from coccoliths
- may contain fossils, form in low energy deep water
- flint nodules are common
- may contain fossils, form in low energy deep water
- flint nodules are common
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micritic limestones
- a fine, hard crystalline limestone formed from calcite mud which has undergone diagenesis
- tend to form from MORS, as they are above the CCD allowing carbonate to accumulate
- burial and diagenesis of this ooze creates micritic limestones
- buried as
- tend to form from MORS, as they are above the CCD allowing carbonate to accumulate
- burial and diagenesis of this ooze creates micritic limestones
- buried as
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modeling sedimentary processes
- deposition & settling velocity
- flocculation of clay particles
- flocculation of clay particles
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deposition & settling velocity
- we can observe how grains are transported, but there are factors which we need to consider
- the size and density
- stokes law
- the size and density
- stokes law
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flocculation of clay particles
clay particles have slow settling velocities
- flocculation is where they adhere to one another to form larger particles to settle faster
- clay particles have negative charges which attracts cation
- only happens during turbulence or movement in estuari
- flocculation is where they adhere to one another to form larger particles to settle faster
- clay particles have negative charges which attracts cation
- only happens during turbulence or movement in estuari
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deposition of turbidites
- sediment which is brought to the sea by rivers accumulates on the continental shelf, eventually as it piles up it becomes unstable and loses shear strength and it moves down due to gravity
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turbidity current
- they are fast, very turbulent and incorporate water as they move
- transport huge volumes of material
- lots of the sediment is deposited as submarine fans on the continental rise or in trenches, but can also spread across abyssal plains
- transport huge volumes of material
- lots of the sediment is deposited as submarine fans on the continental rise or in trenches, but can also spread across abyssal plains
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bouma turbidite model
shale - when there is just pelagic fallout
fine sandstones and siltstones - just low energy
- greywacke - climbing ripples form because rate of deposition has exceeded the rate of migration of the normal ripples
fine sandstones and siltstones - just low energy
- greywacke - climbing ripples form because rate of deposition has exceeded the rate of migration of the normal ripples
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bouma turbidite model
- coarse/ medium sandstone - higher energy form pits & grooves
-coarse pebbles/ granules - highest energy, erosion tears up underlying shale and creates rip-up clasts
-coarse pebbles/ granules - highest energy, erosion tears up underlying shale and creates rip-up clasts
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biogenic deposits
- calcareous and siliceous oozes
-when planktonic organisms die, their tests sink to the sea floor and get preserved as microfossils
- the composition of the ooze depends on the composition of the organism
-when planktonic organisms die, their tests sink to the sea floor and get preserved as microfossils
- the composition of the ooze depends on the composition of the organism
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silicic oozes
form from the skeletons of diatoms in deposits nearer the poles and radiolara in deposits nearer the equator
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deposition in deltaic environments
- deltas occur when rivers flow into a sea\lake, loses energy and deposits its load, with the coarsest being deposited first
- there must be minimal wave action to allow this sediment to build up
- deposition causes the river channels to become blocked s
- there must be minimal wave action to allow this sediment to build up
- deposition causes the river channels to become blocked s
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delta top
- peat -> coal
- peat -> coal
the upper surface of the delta is dominated by distributary channels with swamps, bays or flood plains in between
- coarse grained sands and gravels are deposited in the channels which make up the bulk of the topsets and from channel sandstones
- cross
- coarse grained sands and gravels are deposited in the channels which make up the bulk of the topsets and from channel sandstones
- cross
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delta front
where the river meets the sea
- corse sand is deposited in crescent shaped bars
- crests contain clean sand as waves remove finer material
- lower down there will be finer sands and silts
- marine fossils may be found
- corse sand is deposited in crescent shaped bars
- crests contain clean sand as waves remove finer material
- lower down there will be finer sands and silts
- marine fossils may be found
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prodelta
- the low energy, deeper water
- sediments deposited here are bottomsets and consist mainly of clays and silts
- they lithify to form shale which may contain marine fossils
- sediments deposited here are bottomsets and consist mainly of clays and silts
- they lithify to form shale which may contain marine fossils
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deltaic sequences
- coarsens upwards
- may repeat many times due to subsidence and emergence
- subsidence and emergence may be caused by changes in sea level, local isostatic changes or sedimentation rates
- limestones found at bottom
- bioturbation and trace fossils a
- may repeat many times due to subsidence and emergence
- subsidence and emergence may be caused by changes in sea level, local isostatic changes or sedimentation rates
- limestones found at bottom
- bioturbation and trace fossils a
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banded iron formations
- units of rocks of archean and palaeoproterozoic age, they consist of repeated thin layers of dark iron oxides mainly hematite and magnetite
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walther's law of facies
- in a sedimentary sequence, a vertical succession of facies represents sedimentary environments which once existed side by side and have migrated over one another through time
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Other cards in this set
Card 2
Front
weathering
Back
the breakdown of rocks in situ
( the chemical alteration and mechanical breakdown of rocks by exposure to the atmosphere, water and organic matter
( the chemical alteration and mechanical breakdown of rocks by exposure to the atmosphere, water and organic matter
Card 3
Front
3 categories of weathering
Back
Card 4
Front
chemical weathering
Back
Card 5
Front
carbonation
Back
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