![Page 1: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/1.jpg)
The Sea Floor
![Page 2: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/2.jpg)
Layers of the Earth
Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F)
Mantle – mostly solid, but it is so hot the rock is just about to melt. This allows the mantle to flow (magma) Lithosphere – top part of upper mantle
between mantle and crust Asthenosphere – below Lithosphere
![Page 3: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/3.jpg)
Layers of the Earth (con’t.)
Crust Continental (mostly granite) Oceanic (mostly basaltic rock, more dense)
The outer most layer Up to 30 miles thick 2 kinds of crust
Oceanic (under oceans) Continental (under continents)
Oldest is 3.8 billion years The crust floats on the mantle and moves
around
![Page 4: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/4.jpg)
![Page 5: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/5.jpg)
Alfred Wegner The 1st to propose
Continental Drift Theory (1912)
At first was not widely accepted because:
1. He was a meteorologist not a geologist
2.Could not explain how continents drifted
3. Jigsaw puzzle model of continents had gaps
He named the super-continent “Pangaea”
![Page 6: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/6.jpg)
![Page 7: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/7.jpg)
Continental Drift & the Changing Ocean
200 million years ago, Pangaea was surrounded by a giant ocean called “Pantalassa”
~ 180 million years ago Pangaea began to drift apart
2 main continents were formed Laurasia Gondwana
![Page 8: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/8.jpg)
![Page 9: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/9.jpg)
![Page 10: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/10.jpg)
Marine Biology 5th Ed.Fig. 2.4 pg 25
![Page 11: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/11.jpg)
Seafloor Spreading Theory Used evidence to state the continents rested on
large plates and drifted Evidence used to support the theory
includes: Discovery of mid-ocean ridges (underwater
mountain ranges) Transform faults Trenches Magnetic Anomalies Rifts Fossils on the continental borders match up Rock composition also matches up Glacial Deposits Sediment layers
![Page 12: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/12.jpg)
Mid – Ocean Ridges
![Page 13: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/13.jpg)
Creation of the Sea Floor
New sea floor is made at the ridges When the sea floor spreads, it creates
rifts (cracks) Lava flows out of the rifts and forms new
sea floor This is called sea floor spreading
![Page 14: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/14.jpg)
![Page 15: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/15.jpg)
The ship Glomar Challenger.
![Page 16: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/16.jpg)
Theory of Plate Tectonics
Continental Drift and Seafloor Spreading Theories united
A dozen separate plates Plates float on the asthenosphere Plates are propelled by convection under
the plate
![Page 17: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/17.jpg)
Plate Tectonics Where 2 plates meet is called a plate
boundary (fault) 3 types of motions:
Divergent – 2 plates move apart Creates mid-ocean ridges, mountains, islands
and rift valley
Convergent – 2 plates collide Creates trenches and island or volcanic arcs
Transform – 2 plates slide past each other Creates earthquakes
![Page 18: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/18.jpg)
Kobe Earthquake Japan, 1995
![Page 19: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/19.jpg)
![Page 20: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/20.jpg)
Geologic History of the Earth
If we realize the earth is moving, we can work backwards to see what it used to look like
Since the continents are still moving, 200 million years from today, the earth will look different from what we see now
![Page 21: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/21.jpg)
The Deep Sea Floor
The deep sea floor averages ~13,000 ft deep
It is also called the Abyssal Plain The abyssal plain is mostly flat with some
mountains
![Page 22: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/22.jpg)
Characteristics of Hydrothermal Vents:
-hot water around rift valleys and mid-ocean ridges which is heated by the hot magma
-water carries high levels of hydrogen sulfide
-Organisms such as clams, giant tubeworms, and crustaceans
![Page 23: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/23.jpg)
An image generated with sonar of the President Jackson Seamounts in thePacific Ocean42º 30.60' N 127º 46.20' W
![Page 24: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/24.jpg)
54º 34.80' N 150º 26.40' W
![Page 25: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/25.jpg)
The End
![Page 26: The Sea Floor. Core – mostly iron Inner core – solid Outer core – liquid (temp. ~ 7,200° F) Mantle – mostly solid, but it is so hot the rock is](https://reader036.vdocuments.site/reader036/viewer/2022062423/5697c01c1a28abf838ccfe87/html5/thumbnails/26.jpg)
Pangaea of Not?
Rubric
Plot all the Points /10
Letter*Findings*Dear*Sincerely
/10
Neat /5
Total /25