Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean...

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Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made and why are they so dangerous?

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Transcript of Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean...

Page 1: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Creation, Aging and Recycling of the Ocean

Floor

Creation, Aging and Recycling of the Ocean

FloorHow is the ocean floor made?

Why does the ocean floor get deeper with age?

How are volcanic arcs made and why are they so dangerous?

How is the ocean floor made?Why does the ocean floor get deeper with

age?How are volcanic arcs made and why are

they so dangerous?

Page 2: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Formation of Ocean Formation of Ocean LithosphereLithosphere

Page 3: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Formation of Ocean Lithosphere

Mid-ocean ridges-- global circuit of plate divergence-- youngest ocean floor-- shallowest ocean floorArchitecture of oceanic plates-- seismic profiling-- ocean drilling-- fossil slivers of ocean floor

Page 4: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Seismic Profiling (sound energy)

Seismic Profiling (sound energy)

Page 5: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Ocean DrillingOcean Drilling

International program(20 nations; began 1968)

2-month cruisesDeepest hole: 2 km

But, new vessel will drillto >6km!

International program(20 nations; began 1968)

2-month cruisesDeepest hole: 2 km

But, new vessel will drillto >6km!

Page 6: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Fast vs. Slow SpreadingFast vs. Slow Spreading

Fast Spreading Ridge(10-20 cm/yr)

Slow Spreading Ridge(1-5 cm/yr)

Page 7: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Mid-Ocean Ridges

Uniform process of mantle melting, lava freezing- magma chambers- effects of spreading rate- segmentation

Page 8: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Ocean Crust LayeringOcean Crust Layering

Page 9: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

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Page 10: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

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Page 11: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Mineralized Volcanic Breccia

(1027-1029 mbsf)o

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10 cm

Page 12: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Sea floor deepens with distance from the spreading ridges -- why?Sea floor deepens with distance from the spreading ridges -- why?

Page 13: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Plate Aging involves heat loss through Conductive Cooling

Relation: Depth increases with the square root of age

Page 14: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

A New View on Plate CoolingAdam & Vidal, Science, April 2, 2010

Page 15: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

And, heat loss through Hydrothermal Circulation

Page 16: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Hydrothermal CirculationHydrothermal Circulation

Page 17: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Hydrothermal Circulation

• Natural consequence of porous, hot rock and seawater• Chemical exchange• Fluid venting -- black smokers• Chemosynthetic ecosystems• Crack sealing and sedimentation

Page 18: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Hydrothermal Vent SitesHydrothermal Vent Sites

Page 19: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Hydrothermal Vents VideoHydrothermal Vents Video

Page 20: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

The ocean floor ages and accumulates sediments

The ocean floor ages and accumulates sediments

Page 21: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Plate Aging and Recycling

Slab sinking -- denser than asthenosphere

Page 22: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Plate Subduction and MeltingPlate Subduction and Melting

Page 23: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Pacific NWPacific NW

Page 24: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Mt St HelensMt St Helens

Water, from slab, promotes mantle melting and leads to explosive danger of arc volcanoes

Page 25: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Krakatoa (1883)Tambora (1815)

Page 26: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Toba (71,000 B.C.)

-3000 times as big as Mt St Helens-- Sulfuric acid and dust blocked sunlight, reducing temperatures 5°C for several years

- May have reduced human population to <5000!

Page 27: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Mt HoodMt Hood

Page 28: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Broken TopBroken Top

Page 29: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Three SistersThree Sisters

Page 30: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Crater Lake (Mt. Mazama)Crater Lake (Mt. Mazama)

Page 31: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

Volcanic ash (tephra)Volcanic ash (tephra)

Page 32: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.
Page 33: Creation, Aging and Recycling of the Ocean Floor How is the ocean floor made? Why does the ocean floor get deeper with age? How are volcanic arcs made.

The Ocean Floor --subsurface topography--hinsleyeastcobbmiddle.weebly.com/.../ocean_floor.pdf · 3D model of ocean floor (as a group) •After you build the ocean floor, use toothpicks

The Ocean Floor --subsurface topography--hinsleyeastcobbmiddle.weebly.com/.../ocean_floor.pdf · 3D model of ocean floor (as a group) •After you build the ocean floor, use toothpicks

Chapter 14 The Ocean Floor. Section 14.2 Ocean Floor Features.

Chapter 14 The Ocean Floor. Section 14.2 Ocean Floor Features.

Ocean Zones & Ocean Floor

Ocean Zones & Ocean Floor

Ocean floor

Ocean floor

The Ocean Floor

The Ocean Floor

Earth Science 14.2 F eatures of the Ocean Floor. Ocean Floor features Oceanographers studying the topography of the ocean floor have divided it into three.

Earth Science 14.2 F eatures of the Ocean Floor. Ocean Floor features Oceanographers studying the topography of the ocean floor have divided it into three.

BASIN OCEAN FLOOR

BASIN OCEAN FLOOR

Ocean Bathymetry Topography of the ocean floor. Main Regions Continental Margins – drowned edges of the continents Deep-ocean Basins – the ocean floor.

Ocean Bathymetry Topography of the ocean floor. Main Regions Continental Margins – drowned edges of the continents Deep-ocean Basins – the ocean floor.

Ocean floor topography

Ocean floor topography

Ocean Floor Field Developmentdril-quip.com/resources/catalogs/27. Ocean Floor Development.pdf · Ocean Floor Field Development ... esses, which are defined at the start of a project

Ocean Floor Field Developmentdril-quip.com/resources/catalogs/27. Ocean Floor Development.pdf · Ocean Floor Field Development ... esses, which are defined at the start of a project

G Ground Ocean Floor

G Ground Ocean Floor

Ocean Notes. I. Features of the Ocean Floor A. There are 3 major regions on the ocean floor Continental Margin Ocean Basin FloorMid Ocean Ridge.

Ocean Notes. I. Features of the Ocean Floor A. There are 3 major regions on the ocean floor Continental Margin Ocean Basin FloorMid Ocean Ridge.

Mapping The Ocean Floor

Mapping The Ocean Floor

OCEAN FLOOR TOPOGRAPHY - ketteringschools.org

OCEAN FLOOR TOPOGRAPHY - ketteringschools.org

Journey to Bottom of the Ocean Ocean Floor

Journey to Bottom of the Ocean Ocean Floor

CHAPTER 3 Marine Provinces. Measuring bathymetry Ocean depths and topography of ocean floor Ocean depths and topography of ocean floor Sounding Sounding.

CHAPTER 3 Marine Provinces. Measuring bathymetry Ocean depths and topography of ocean floor Ocean depths and topography of ocean floor Sounding Sounding.

14.2 science OCEAN FLOOR The ocean floor regions are the continental margins, the ocean basin floor, and the mid-ocean ridge. Scientists have discovered.

14.2 science OCEAN FLOOR The ocean floor regions are the continental margins, the ocean basin floor, and the mid-ocean ridge. Scientists have discovered.

Ocean Floor Lecture - Jack & Katie...Ocean Floor Lecture Slide 1 “Seeing” the Ocean Floor • Light doesn’t penetrate to the ocean floor so we must use other means to “see”

Ocean Floor Lecture - Jack & Katie...Ocean Floor Lecture Slide 1 “Seeing” the Ocean Floor • Light doesn’t penetrate to the ocean floor so we must use other means to “see”

Chapter 14.2 Ocean Floor Features. The ocean floor has 3 major regions – the continental margins, the ocean basin floor, and the mid- ocean ridge.

Chapter 14.2 Ocean Floor Features. The ocean floor has 3 major regions – the continental margins, the ocean basin floor, and the mid- ocean ridge.

Sea Floor Spreading The Mid-ocean Ridge Vocabulary Mid-ocean ridgeMid-ocean ridge SonarSonar Sea-floor spreadingSea-floor spreading Deep-ocean trenchDeep-ocean.

Sea Floor Spreading The Mid-ocean Ridge Vocabulary Mid-ocean ridgeMid-ocean ridge SonarSonar Sea-floor spreadingSea-floor spreading Deep-ocean trenchDeep-ocean.