Lecture 2 Flashcards
Permafrost
soil and sedimentation that have remained frozen for two or more consequtive years
active layer of soil( in terms of permafrost)
is the seasonally frozen ground on top of subsurface permafrost-thaws every summer
in winter the active layer freezes, trapping plant and animal material before it can decompose completley
-creates carbon rich soils
carbon in permafrost is ___ the ammount stored in the atmosphere
twice
endogenic system
exogenic
consists of proccesses operating in earths interior driven by heat and radioactive decay
processes operating at earths surface driven by solar energy and movement of air, water, and ice
eons
eras
periods
epochs
largest time span
Shortst
EpochHolocene
Eon: phanerozoic
the current era is the _______
cenozoic(quaternary period)
Earths core is a / of earths mass and a / of its volume
1/3, 1/6
inner and outer core are seperated by th ______ zone
inner core is solid ____
outer core is _____
Outer core is seperated from mantle by a transition zone seveeral hundred km wide at a depth of ____
lower and upper mantle represent __% of earths volume
transition
iron(remains solid despite heat because of pressure)
molten, metalic iron with lighter density
2900km
80
________ discontinuity occurs at a depth of about 2900k between outer core and lower mantle
________ discontinuity occurs between uppermost mantle and crust
Glutenburg
Mohorovicic(moho)
-seismic waves change at this depth due to sharp contrasts in material composition and density
7 segments of earths depth(deepest to shallowest)
Inner core Outer Core Lower Mantle Upper Mantle Asthenosphere Uppermost Mantle Continetal Crust
crustal thickness is thickest beneath ______ at 50-60km
30 km thickness beneath _______
5km thickness beneath _______
mountain
continental
oceanic
______ and _____ make up __% makes up earths crust
Oxygen and silicon
74%
-more oxygen in crust than atmosphere
continental crust is ___ in density in comparison to oceanic= 2.7 vs. 3.0
Continental composed of ______
oceanic composed of _______
lower
Granite
Basalt
Lithosphere vs Asthenosphere
- Rigid Layer
- crust and uppermost mantle to about 70 km
- plastic layer
- within mantle from 70km to 250km
- convection currents in this zone in part causes the shifting of lithospheric plates
Are crust and lithosphere the same?
No, the crust makes up the upper portion of the lithosphere
isostasy
the balance between the buoyancy and gravitational forces
-explains elevations of continents and the depths of ocean floors as determined by vertical movements of earths crust
isostatic rebound
if the load is removed, such as when a glacier melts, the crust rides higher and the astenosphere flows back toward the region of uplifting lithosphere
Earths fluid outer core generates most of earths ______ field
magnetic
-circulation in the outer core converts thermal and gravitational energy into magnetic energy
95% o earths crust is made up of ______
silicates
Igneous Rock
one that solidifies and crystallizes from a molten state
- makes up approximately 90% of earths crust
- coarse if beneath the surface like granite
- finer grained from fast cooling at surface is basalt
Pluton
.intrusive igneous rock that cools slowly in the crust forms…
-largest plutonic form is Batholith
Sedimentary Rock
-4 types
.Driven by solar energy and gravity
1.Clastic:Weathering, Deposition, Lithification
- Biochemical:dissolved minerals build up to form rocks
- ex:limestone - Organic:
- Chemical:dissolved minerals build up to form rocks
CAN BEES OPEN CANS?
Lithification
occurs as loose sediment is hardened into solid rock
Metamorphic
.any igneous or sedimentary rocks can be transformed into metamorphic by going through physical and chemical changes under pressure and increased temp
caused by: heating, pressure, heating and pressure together, and compression and shear
Foliated rock
has a banded or layered appearance
Geological cycle made up of three main internal cycles:
Hydrological
Rock
Tectonic
3 orders of relief
- Continents and oceans
- intermediate level of landforms like mountain masses, underwater continental rises
- most detailed order of relief includes individual mountains, cliffs
Hypsometry
Bathymetry
measurement of land elevation relative to sea level
same thing but underwater
Earths diameter in km?
Average elevation of earths solid surface?
12,756 km
-2070 m so under sea level
.oceans are much deeper than continents are high
Subduction and connected eruptions, which may not reach the surface, are ____ rich in comparison to eruptions that come straight from the aesthenosphere
silica
terranes
pieces of land mass which eventually becomes a part of continents
crustal deformation caused by 3 things
___ is the measure of the ammount of deformation undergone by an object
- Tension=causes stretching
- -Normal fault - compression: causes shortening
- causes folding(think of pushing cloth in together on both sides)
- Thrust or Reverse fault - shear: causes twisting or tearing as objects slife parallel to one another
- strike-slip fault(lateral shearing)
Strain
Faulting
occurs when rocks on either side of the fracture shift relative to the other side
Orogenesis
caused by 3 things
geological term for mountain building
. folding, faulting, and volcanism
3 different types of lithospheric plate collisions result in mountain building
- oceanic plate continental plate
- subduction zone forms
- magma erupts to the surface through continental plate, vlcanic mountains form.
ex: andes of south america - oceanic-oceanic
- subduction zone forms
- magma forms above the descending plate, giving rise to volcanic island arc
ex: Japan - continential-continental
- neither plate is subducted
- powerful compression force folding,faulting, and uplift pushing up huge mountain ranges
ex: Himilayas
Tectonic earthquakes are those quakes associated with _______
faulting
The pacific coasr is the most seismically active region in canada, one of the few regions in the world where _____,_______, and ______ plate boundaries occur in proximity to one another
transform, divergent, convergent
Elastic Rebound Theory
when two sides are locked in position by friction, eventually elastic energy is so built up when it releases it is huge
Volcanic Activity occurs in three settings
Along subduction boundaries at continental plate-oceanic plate convergence
along sea floor spreadinf centert on the ocean floor
hot spots
Effusive Erruptions
Explosive Volcanoes
are ourpourings of low viscocity magma that produce enourmous volumes of lava annually on the seafloor and in places such as Hawaii and Iceland.
- flow directly from aestenosphere and upper mantle
- low in silica, high in iron
are violent explosions of magma driven by the buildup of pressure in magma conduit
- created by subducting plate and other thicks materials than magma which forms effusive volcanoes
- material blocks magma conduit by forming plug and only releasing after much built up pressure
- much less lava than effusive, but larger ammounts of pyroclastics like volcanic ash
- a mountain produces by a series of explosive volcanoes is called a composite volcano or stratovolcanoes because of many layers
ex: Mount St.Helens, Cali
scarification
results from such human cause mass movements instead of gravity as the agent which drives natural processes, most mass movement related to human accitivity is done by machines and the burning of fossil fuels
Weathering vs Erosion
is the break down of materials
transport of weathered materials to different locations
Denundation
is any process that wears away or rearanges landform
geomorphic threshold
tipping point, where the system lurches to a new operational level when abrupt change occurs
the upper surface of bedrock undergoes continual weathering, creating broken up _____
REGOLITH
sppheroidal weathering
is chemical weathering that softens and rounds the sharp edges and corners of jointed rock as water penetrates the joints and dissolves weaker minerals or cemmenting materials
Karst topography
certain areas of the worl with extensive lime-stone formations, chemical weathering involving dissolution of carbonates dominates entire landscapes
ex: limestone
- sinkholes,karst valleys(bunch of sinkholes together),caves and caverns, towers
- limestone formations must contain 80% or more calcium carbonate
- complex patterns of joints in the otherwie imperiable limestone
- aerated zone must exist between ground surface an water table
- vegetation covers is needed to supply varying ammounts of organic acids
define mass movement/mass wasting
downslope movement of a body of material made up of soil, sediment, or rock propelled by the force of gravity
-can occur on land or underwater
angle of ______: the steepness of the resulting slope
repose
if 40-60 degree angle then oversteepened
4 classes of mass movement
fall, slide, creep, flow
Movement type dependent on volume of material, moisture content, and rate of movement
Rockfall
Soil Creep
Rotational Slide
Earthflow
Transitional Slide
Debris Avalanche
Mudflow
Solifluction
- a volume of rock that falls through the air and hits a surface
- is a mass falling and timbling of rock,debris, and soil
- involve movement along a flat surface roughly parallel to the angle of slope, with no rotation
3.(slumps) occur when surface material moves along a concave surface
7&4. One has more moisture content in moving material
2(drier),8(wetter)- slow moving
5,3,&4- Intermediate speed and water content
1(Drier),6(Intermediate),7(Wetter)-Fast moving
processes related to streams and rivers are called _____
fluvial
Drainage basins are ____ systems(open or closed)
open
drainage density is determined by deviding the ___________________ by the ______ of the basin
total length of all stream channels in the basin by the area of the basin
Drainage Patterns:7
Determined by regional steepness and relief; variations in rock resistance; climate; hydrology; structural controls from underlying rocks
- Dendritic(most familiar)
- treelike pattern
- similar to many natural patterns like human circulatory system
- effecient at moving water and sediment because branch length is minimized - Rectangular
- is formed by faulted and jointed landscape, which directs stream course patterns of right-angle turns - Trellis
- characteristic of dipping or folded topography
- parallel structures - Annular
- occur on structural domes, with cconcentric patterns of rock starta guiding stream courses - Radial
- when streams flow off central peak or dome, like volcanic mountain - Deranged
- no clear geometry and no true stream valley occurs in areas such as glaciated shield regions of canada and northern eruope - Parallel
- associated with steep slopes
Superposed stream-in which a prexisting chanel pattern has been imposed upon older underlying rocks structures
DR.TARDP
energy of a stream to accomplish geomorphic work such as transport, eropsion, and deposition is dependant on factors including…(3)
gradient
base level
- level below which a stream cannot erode its valley
- ultimate base level is sea level
volume of flow
Q=wdv
Q=Discharge
w=Channel Width
d=Channel depth
v=stream velocity
Perrenial, Ephermeral, Intermittent discharge
Perrenial:flow all year
Ephemeral:flow only after precipitation events and are not connected to groundwater streams
Intermittent: flow for several weeks or months each year and may have some groundwater inputs
hydrograph
a graph of stream discharge over time for specific location
Hydraulic action
headward erosion
is the type of erosive work performed by flowing water alone
-maximum at upstream tributaries where sediment load is low and flow is turbulent
streams lengthen their channels upstream
Sediment is moved as _____ load, ______ load, or ____ load by four primary proccesses:
Dissolved Load-material that travels in the solution
Suspended Load-consists of fine-grained clastic particles held aloft until stream velocity slows nearly to zero
Bed Load-coarser materials that are moved by traction, which is rolling or draggin matterial
- Solution
- Suspension
- Saltation
- refers to the way partiles may bounce along in short hops or jumps
- particles to large to remain afloat but are not confined to the sliding and rolling actions - Traction
- rolling or dragging of materials along the stream bed
_______ is the process by which the load exceeds a streams capacity, sediment accumulates in the bed and the stream channel builds up through deposition
aggradation
Multiple Thread Channels
Single Thread Channel
braided or anabranching, tend to occur in areas with abundant sediment or in the lowest reaches of large river systems
-braided is a stream with a maze of interconnected channels, occurs when discharge lowers a streams transportation ability or when sediment load increases
are either straight or meandering
- straight channels tend to occur in headwater areas where gradient is high
- meandering tend to occur in lower gradient areas with finer sediments and is more commkon
- undercut banks are common as faster water erodes outside faster, point bar occurs because of slow pace of inside curve
- oxbow lake
alluvium
Yazoo streams
unconsolidated clay, silt, and sand deposited by running water
flow parallel to the main river but are blocked from joining because of natural levees
average salinity of sea water worldwide is __%
______ is a term used to apply to water with less then 35% salts
35
-direct correlation between salinity and evaporation/precipitatiion
high salinity=high evaporation
brackish( ex: seawater near sweden)
Physical Structure of ocean(3)
Mixing zone:
- represents only 2% of ocean
- warmed by sun, mixed by winds
- temperature the same throughout
Thermocline transition zone:
- 18% of ocean
- more than 1km deep
- no motion, temp decreases with depth
- friction at these depths dampens affects of surface currents
- no convective movements
Deep Cold Zone:
- 1km to ocean floor
- temp and salinity are uniform
- temps near 0 degrees with coldest along ocean bottom
ocean average ph is __, could decrease by __ units this century
Why?
- 2
- 4
As the oceans absorb excess carbon dioxide from the atmosphere, the process of carbonation forms carbonic acid in the water, resulting in lowe of ocean PH-and acidification
littoral zone
the coastal area and shallow offshore environment
- extends onto land to waterline at hgihest reach
- extends out into see to about 60m in depth where storm waves cannot effect sea floor
Cause of tides
tides are produced by the gravitational pull of both the moon and sun
- moons influence much higher because of proximity
- most coastal locations experience two high tides and two low tides a day
- when sun and moon are aligned is the strongest gravitational pull and greatest tidal range (spring tides)
- (neap tide) occurs when they are on not on either side of eachother or together creating less of an effect
waves of transition:
the water within a wave in the open ocean is transfering energy from molecule to molecule in simplye cyclical undulations
as deep ocean waves come closer to shore, 10 to 20m depths, the orbiting water particles are vertically resticted, causing elliptical, flatened orbits of water particles to form near the bottom
circular to elliptical
Plunging breakers vs. spilling breakers
indicate a steep bottom profile
gentle shallow bottom profile
wave refraction
is a redistribution of wave energy, so that different sections of the coastline wary in erosion potential, with long term effect of straightening coastline
waves come in at an angle meaning that waves which are in deeper water retain velocity and speed for longer
Longshore current(littoral current)
Littoral Drift
the velocity difference refracts the wave, producing a current that flows parallel to the coast, zigzagging in the prevalent direction of the incoming waves
- depends on wind direction and resultant wave directin
- present only in surf where it transports large ammounts of sediment along the shore(beach drift)
Is the term for the combined actionsa of the longshore current and beach drift
Barrier spits
Beaches
Tombolo
Bay barrier
Lagoon
Sea arch
Notched cliff
Terrace
Littoral current
Barrier Islands
Barrier Beach
a
roche moutonee
an asymmetrical hill of exposed bedrock
-has a characteristic gently sloping upstream side(stoss side) that is polished smooth by glacial action and an abrupt and steep downstream side(lee side) where the glacier plucked rock pieces
alluvial fans
prominent cone-shaped deposits of fluvial sediments
- occurt commonly at the mouth of a canyon where ephermeral stream channel exits the mountains into a flatter valley
- happens when water loses velocity coming out of constricted area, dropping layers and layers of sediment
sinuous/convoluted
many curves or turns
Describe each dune form:
Barchan
Transverse
Parabolic
Longitudinal
Barachnoid ridge
Longitudinal
Star dune
Dome
Star Dune
Reversing
Erg(NOT A DUNE TYPE)
a
corals are made of ____ _____
calcium carbonate
corals are made of ____ _____
3 types
coral bleaching
calcium carbonate
Fringing, Barrier, Atoll
normal corals turn stark white by expelling their own nutrient supplying algae
Eolian Transport is transport by ____
_____ sized grains are moved easier
wind
intermediate
-work only on dry materials
Deflation
Ventifacts
Yardangs
Desert Pavement
erosion of the ground surface resulting from the lifting and removal of individual particles by wind
rocks which are smoothed out by wind
deflation and abrasion together are capable of streamlining multiple rock structures in a landscape in aligntments parallel to the most effective wind direction
-produces distinctive elongated formations
Hard stoney surface created by wind(deflation) rather then normal sandy surface
Deflation hypothesis vs Sediment accumulation hypo
Both are for describing how sand deserts happen
- first one believes wind takes all smaller particles away
- 2nd thinks water forces smaller particles down leaving larger rocks above
glaciers form by..
firn
the continual accumulation of snow that recrystalizes under its own weight into an ice mass
a granular partly compacted snow that is intermediate between snow and ice
two general groups of glacier types
- alpine glaciers
- valley glacier are masses of ic confined within a valley originally formed by a stream
- cirque is formed within the snow filling a cirque or bowl shaped recess at the head of a valley
- piedmont glacier is formed wherever several valley glaciers pour out of their confining valleys and coalesce at the base of a mountain range - continental ice sheets
- a edge of ice sheets are ice shelves
- ice caps and ice fields are slightly smaller
- ice cap is circular
- ice field extends in a characteristic elonggated pattern over a mountanous region but is not as extensive as an ice cap
glacier accumulation zone ends at its ____ line
Collectively, processes which act to waste/reduce glaciers cause it to lose mass which is called _____
firn line
-marks the elevation above which the winter snow and ice remained intact throughout the summer melting season
ablation
_____ portion of glacier flows ahead of _____ portion
ice regelation
water works to lubricate ____ layer
upper, bottom
melting and refreezing action incorporates rock debris into the glacier, bottom has much higher debris content than top
basal
moraine(3)
lateral: in areas that have undergone alpine glaciations, these are lengthy ridges of till along each side of glacier
medial: if two glciers with lateral moraines join
terminal: accumulate at glaciers terminus or endpoint and are associated with both continental and alpine
ground: is a deposition of till that forms behind a terminal moraine as the glacier retreats and is generally spread widely accross the ground surface, creating irregular topography but not characteristic moraine ridges
glacial drift
drumlins
stratified drift
general term for all glacial deposits unsorted and sorted
hills of deposited till are streamlined in direction of receding glacier
sediments deposited by meltwater are sorted by size
permafrost
when soil, sediment, or rock temperatures remain below 0 for at least two years
solifluction and gelifluction
flow of saturated soil from higher elevation to lower with inclination
if the same thing occurs but in ice-bound type with permafrost or ground ice
6 Main Soil Horizons
Solum
O-named because of organic composition
A(topsoil)-richer in humus than lower horizons,high in silt
Ae- coarse sand and silt, e(eluviation) is for water carrying fine particles down and leaving behind sand and silt
B-accumulate clays, aluminum and iron
- dominated by illuviation in which materials leached by water from one layer enter and accumulate in another
- in other words deposition in this layer
C-made up of weathered bedrock or parent material
- regolith
- no biological input in this layer
- more silt and sand then clay
R-unconsolidated material or consolidated bedrock
Solum: A AE B horizons together are solum
Pedogenic Regimes(5)
Laterization: a leaching process active in humid and warm climates-tropics and subtropics
Salinization: a process that concentrates salts in soils in climates with excessive potential evapotranpiration rates
calcification: a process that produces an illuviated accumulation of calcium carbonates in continental climates
podsolization: a process of soil acidification associates with forest soils in cool climates
gleysation: a process that includes an accumulation of humus and a thick, water saturated grey layer of clay beneath, and is usually found in cold, wet climates and poor drainage conditions
Listen Sally Cats Play Guitar
CSSC LEVELS(5)Largest to smallest
- Order-10 soil orders
- Great Group
- Subgroup
- Family
- Series
ORDER GREAT SOUP FROM SIRI
Saskatoon soil order is _______
chernozernic
of the total energy intercepted at earths surface and available for work, only about __% is actually fixed by photosynthesis as carbohydrates in plants
1
Photosynthesis is:
______+_____+______–>______+________
respiration is opposite
carbon dioxide+water+solar energy–>glucose+oxygen
oxygen and carbon cycles
Nitrogen
oxygen principal resevoir is atmos
ocean for carbon
78.1% of atmosphere
ecotones
boundaries between natural systems, transition area
core
Core: inner and outer, same temp of the sun 6000 degrees celcius, enormous pressure, made up of iron and nickel, 6400 km deep
lithosphere
Lithosphere: surface, solid rock, and upper part of the Mantal
-zone of rigid, brittle rock
-consists of oceanic crusts, continental crust, and uppermost mantle
-thickness from 60-150 km, thickest under continents, thinner under oceans
.MOHO zone density changecrust goes from brittle to soft material, bottom most part of lithosphere
Astenosphere
.Asthenosphere-key to understanding plate tectonics, a soft and plastic rock layer, density of astheno is higher then continental and oceanic crust, “hard” lithosphere above, mant rock layer below
Extrusive vs. Intrusive Igneous rock
Extrusive vs intrusive igneous rock:
-cools and hardens at the surface vs. cools and hardens before it comes to surface
water covers __% of the global surface
71
Effluent vs. Influent Water
Effluent: Groundwater interaction with stream flow; water being released into a water body(stream)
Influent: Groundwater interaction with stream flow; water being released into ground water body
-not loss of water volume in stream channel
What is Saskatoon’s river basin?
South SK river basin
Wave Process Deep to Shallow
- in deep water, wavelengths are longer and have relatively low wave heights
- motion is CIRCULAR (OSCILLATORY), water molecules are moving up and down while rotating forward - transitional waves: higher in height, wave length becomes narrower and narrower, more ELLIPTICAL then circular
- In shallow water, closer to show is the translation
3 types of waves breaking
. Spilling: break gradually over a considerable distance, because of changes in depth
. Plunging: tend to curl over and break with a single crash
. Surging: surge onto the beach without spilling or plunging, steep bottom
6 coast types
Coastline types:
- . Ria coast
- submerging, creating sandspits, affected by rising sea levels, low elevation - Fjord coast
- formed by glaciers, very deep water, inlets and bays, very steep cliff walls - Barrier Island
- soft and unconsolidated material, sedimentary rock, easily moved, higher water levels - Delta Coast
- extremely fertile areas because of sediments from continents,
- birdsfoot delta is when land looks like that coming out into water - Volcano coast
- plat margins causing subduction, alpine chains of volcanoes
- residual volcanic cones are just the peak with the rest eroded away (ex: Hawaiian Island Chain) - fault coast
- former wavecut beach/platforms become exposed, can tell you how old a coastline is
gravitational attraction from moon and sun effects (3)
water, atmos, and crust
inactive vs active dunes
- ACTIVE dunes as there is no vegetation and is free to move
- INACTIVE dunes occur all around the south of Saskatoon and are covered in vegetation
__ degree angle is the point where gravity exceeds ability of particles to hold position on slipface for stuff like sand dunes
34
_____ dunes can be found in SK
Barcan
Loess Deposition
Loess(loose) deposition:
. silt-sized sediment
-formed by accumulation of wind-blown dust
-10% of the Earths land area covered by loess or similar deposits
-clays and silts
. Fines
-moved great distances from source regions
. wind-lain silts and fine sands form homogenous deposits
. at end of last glacial period, Sask was barren with open rock face, material carried very far south over thousands of years to the states
. can be 10s of meters in depth
-VERY FERTILE
. found in china, Alaska, and Central US
-in central US came from SASK
gLACIERS DEVELOP IN STAGES(3)
.glacial ice develops in stages
.fresh snow neve firn(final stage before turning to ice)
______ ICE FIELDS are closest to SK
Columbia ICE FIELDS-closes to SK
Glacial Valleys: How they come to be
V to U
Glacial Valleys: transformation of stream valleys: glacial erosion removes soils and much of the regolith, thus widening and deepening the valley over time to create a GLACIAL TROUGH
In ________ glaciation the ice sheet over canada was called the ________
Wisconsinan Glaciation:
. Laurentian Ice sheet over Canada
Glacial Lecustrian
Glacial Lecustrian: When glacial deposits settle out into the bottom of the lake
GPP AND NPP
Gross Primary Production (GPP): Energy received and used in photosynthesis
Net Primary Production(NPP):
.Out of the gross primary production, what isn’t respired is NPP
Soil Layers: 7
Define Translocation
- Oi-largely decomposed organic material
- Oa- partially decomposed organic debris
- A- dark coloured horizon of mixed mineral and organic matter with much Biological activity
- E(Eluviation)-light coloured horizon marked by removal of clay particles, organic matter, and or oxides of iron and aluminum
- B- maximum accumulation of silicate clay particles or of ioxides and organic matter
- C-weathered parent material
- Consolidated Bedrock
: movement of material/substances between layers
Mollisols
Mollisols: Close to prairie soils
.Molli=soft
. thick, humus-rich upper layer
Prarie soils are generally basic
Ecoological Units(10)
organelle, cells, tissues, organs, organ systems, organisms, populations, communities, ecosystem, and biosphere
