SC.912.E.6.5
Describe the geologic development of
the present day oceans and identify
commonly found features.
• Earth Structures - The scientific theory of plate
tectonics provides the framework for much of
modern geology. Over geologic time, internal
and external sources of energy have
continuously altered the features of Earth by
means of both constructive and destructive
forces. All life, including human civilization, is
dependent on Earth's internal and external
energy and material resources.
• SC.D.1.4.4: AA (Assessed as F.2.4.3) The student knows that
Earth’s systems and organisms are the result of a long,
continuous change over time.
SC.D.1.4.3: CS The student knows that changes in Earth’s climate,
geological activity, and life forms may be traced and compared. MC
SC.912.E.6.5
Describe the geologic development of the present day
oceans and identify commonly found features.
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14.2 Ocean Floor Features
Online Field Trips
Chapter Quiz
Study Guide Summary (PowerPoint presentation)
Web Quest: Where Would You Take an ROV?
Web Resources
– The Vast World Ocean: Links on oceans
– Ocean Floor Features: Links on ocean floor features
– Resources from the Seafloor: Links on ocean resources
• Animations
QUESTIONS
According to the plate tectonic theory, when oceanic plates collide with
continental plates, the denser oceanic plate is forced under the lighter
continental plate. Which geologic feature is a result of this type of
collision?
• F. hot spot
• G. abyssal plain
• H. midocean ridge
• I. composite volcano
DAY 1
• What are the three main regions of the ocean
floor?
• How do the continental margins in the Atlantic
Ocean differ from those in the Pacific Ocean?
Key Vocabulary
• Continental margin
– Zone of transistion between continent and
adjacent ocean
• Ocean Basin Floor
– Between the continental margin and mid-ocean
ridge
• Mid-Ocean Ridge
– Found near the center of most ocean basins
Label the three main regions:
Continental Margin, Ocean basin Floor, MidOcean Ridge
14.2 Ocean Floor Features
Mapping the Ocean Floor
 The ocean floor regions are the continental
margins, the ocean basin floor, and the
mid-ocean ridge.
14.2 Ocean Floor Features
Continental Margins
 A continental margin is the zone of
transition between a continent and the
adjacent ocean basin floor.
 In the Atlantic Ocean, thick layers of
undisturbed sediment cover the continental
margin. This region has very little volcanic
or earthquake activity.
Atlantic Continental Margin
14.2 Ocean Floor Features
Continental Margins
 In the Pacific Ocean, oceanic crust plunges
beneath continental crust. This force results
in a narrow continental margin that
experiences both volcanic activity and
earthquakes.
Submarine Canyons
VOCABULARY
continental shelf
continental slope
continental rise
submarine canyon
The Continental Margin
The continental margin is the underwater edge of a
continent. It includes the continental shelf, continental
slope, and continental rise, as well as submarine
valleys and canyons.
Continental margin
Continental
slope
Continental shelf
Sediment
Continental crust
Continental
rise
Oceanic crust
Lithosphere
Abyssal
plain
DAY 2
• How do the Atlantic and the Pacific Ocean
differ?
14.2 Ocean Floor Features
Ocean Basin Floor
 The ocean basin floor is the area of the
deep-ocean floor between the continental
margin and the oceanic ridge.
 Deep-Ocean Trenches
• Trenches form at the sites of plate convergence where one
moving plate descends beneath another and plunges back into
the mantle.
14.2 Ocean Floor Features
Ocean Basin Floor
 Abyssal Plains
• An abyssal plain is a very level area of the deep-ocean floor,
usually lying at the foot of the continental rise.
• The sediments that make up abyssal plains are carried there by
turbidity currents or are deposited as suspended sediment settles
out.
 Seamounts and Guyots
• A seamount is an isolated volcanic peak that rises at least 1000
meters above the deep-ocean floor, and a guyot is an eroded,
submerged seamount.
Abyssal Plain Cross Section
The Ocean Basin
Coral reefs can form around volcanic islands. As the
islands sink with the ocean crust, rings of coral are
left behind which continue to grow, forming barrier
reefs and atolls.
Barrier
Reef
Atoll
How would a profile of the pacific Ocean basin
differ from the profile of the Atlantic Ocean?
DAY 3
What is formed at the mid-ocean
ridge?
Create a Venn Diagram to
compare/ contrast the two.
Ocean Floor Features
Mid-Ocean Ridges
 A mid-ocean ridge is found near the center
of most ocean basins. It is an interconnected
system of underwater mountains that have
developed on newly formed ocean crust.
 Seafloor Spreading
• Seafloor spreading is the process by which plate tectonics
produces new oceanic lithosphere at ocean ridges.
• New ocean floor is formed at mid-ocean ridges as magma rises
between the diverging plates and cools.
14.2 Ocean Floor Features
Mid-Ocean Ridges
 Hydrothermal Vents
• Hydrothermal vents form along mid-ocean ridges. These are
zones where mineral-rich water, heated by the hot, newly-formed
oceanic crust, escapes through cracks in the oceanic crust into
surrounding water.
What is formed at the mid-ocean
ridge?
Create a Venn Diagram to
compare/ contrast the two.
DAY 4
• FCIM Quiz