history darwin and the hms beagle 1831-1836 studied barnacles
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HMS ChallengerHMS Challenger led by led by Sir Charles Sir Charles WyvilleWyville Thomson Thomson (1830-1882) (1830-1882)
FindingsFindings
• 4,717 new species;
• The first systematic plot of currents and temperatures in the ocean;
• A map of bottom deposits much of which has remained current to the present;
• An outline of the main contours of the ocean basins; and
• The discovery of the mid-Atlantic Ridge; 1,800 feet, findings such as:
Alexander AgassizAlexander Agassiz
• 1877
• Studied the collaboration of marine animals.
• Founded Woods Hole Oceanographic Institute.
Earth's StructureEarth's Structure• Inner core: 0-1200 km• Outer core: 1200-2500 km• Mantle: 2500-6300 km• Crust: Outer most 100 km
Continental CrustContinental Crust• Crust containing the continents
• thick & less dense
• Made of mostly granite
Plate TectonicsPlate Tectonics
• The Earth’s crust is made up of many plate
that are in constant motion
Plate Boundaries and Geologic Plate Boundaries and Geologic ProcessesProcesses
• The lithosphere is fragmented into fourteen major tectonic plates
• Plates are moving across the Earth's surface in different directions and at different velocities.
• Many geologic processes, such as plutonism, volcanism, and earthquakes result from the interaction of plates along their boundaries
Types of BoundariesTypes of Boundaries• Mid-ocean Ridges
• Subduction Boundary
• Shear Boundary
• Mountain Range
Mid-Ocean RidgeMid-Ocean Ridge• Divergent boundaries
• Spreading center
• Continuous chain of volcanic submarine mountains that encircle the globe
• Like seams on a baseball
Convergent boundariesConvergent boundaries
• formed between two plates that are moving toward one another
• 2 forms
• Subduction
• Collisional
SubductionSubduction• When an oceanic plate
slides under another plate
• Both volcanic and earthquake activity occur
• Forms very deep trenches
Collisional BoundaryCollisional Boundary
• Mountain Range
• Forms when two continental plates collide
Shear (transform) Shear (transform) BoundaryBoundary
• When two plates slide parallel to each other
• Only earthquake activity
• San Andreas Fault
Hot SpotHot Spot• Forms when there is
enough heat upwelling to form a volcano, but not
enough to form a mid-ocean ridge
Active MarginActive Margin• A continental margin that is
geologically active
• A continental margin near a plate boundary
• USA’s west coast
Passive MarginPassive Margin• A continental margin with no
geological activity
• A continental margin not near a plate boundary
• USA’s east coast
SedimentSediment• Loose material like sand or
mud that settles to the bottom of any body of water
• Sediment thickness increases as you move from m-o-r
Sediment is the word geologists Sediment is the word geologists use for loose pieces of minerals use for loose pieces of minerals
and rock. and rock.
Types of SedimentTypes of Sediment• Lithogenous: from a non-living source
• Biogenous: from a living source
Calcareous OozeCalcareous Ooze• Carbon based sediment
• Sediment containing calcium carbonate
• CaCO3
Siliceous OozeSiliceous Ooze• Silicon based sediment
• Sediment containing silicon dioxide or silicates
• SiO2 or SiO4-4
Ocean bottom sediment Ocean bottom sediment mapmap
Ocean bottom sediment map. Lithogenous Ocean bottom sediment map. Lithogenous areas are mauve, biogenous areas are areas are mauve, biogenous areas are
purple and brown (purple = siliceous ooze, purple and brown (purple = siliceous ooze, brown = calcareous ooze), and brown = calcareous ooze), and hydrogenous areas are blue.hydrogenous areas are blue.
Hydrothermal VentHydrothermal Vent
• Oceanic hot spot where hot gases escape
through the ocean floor
Black SmokerBlack Smoker• Another name for
hydrothermal vents
• As hydrogen sulfide gas precipitates in cold water, you get a black precipitate
Passive Margins Passive Margins PartsParts
• Continental shelf
• Shelf break
• Continental slope
• Continental rise
• The Abyss
Continental ShelfContinental Shelf
• Nearly flat, slightly sloping, not too deep
area just off the shoreline
Continental SlopeContinental Slope
• The steeply sloping part of the margin that goes from the shelf break to
the ocean floor
Epipelagic ZoneEpipelagic Zone
• Surface water where light can penetrate & photosynthesis can take place
• Photic zone
Mesopelagic Mesopelagic ZoneZone
Middle zone, just Middle zone, just below the epipelagic below the epipelagic
where no light where no light penetrates, but is penetrates, but is
shadowyshadowy
Twilight zoneTwilight zone
Bathopelagic ZoneBathopelagic Zone• Deep ocean water where no
light penetrates and it is pitch black
• Complete darkness
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