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Climate and Sediment
Summary
Students investigate the different kinds of
sediments present at different locations on
the ocean floor.
Learning Objectives
Students will be able to:
• Interpret a sediment map of the ocean
basins.
• Predict the sediment type they will find
at a given location.
• Describe their observations of a
sediment core.
National Science Education Content
Standards
• Grades 5–8: Earth and Space
Science: Structure of the earth system
• Grades 9–12: Earth and Space
Science: Origin and evolution of the
earth system
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Teaching for Science • Learning for Life | www.deepearthacademy.org
Ocean Literacy Essential Principles
• Earth has one big ocean with many
features.
• The ocean and life in the ocean shape
the features of Earth.
Target Age: Grades 7-12
Time: 40 minutes
Materials
• Core replicas or core photos of
ODP Leg 208-1262B-15H-3, IODP
Expedition 303-1308A-6H-1, and the
K/T boundary core (ODP Leg 171B)
To inquire about the availability of core
replicas, contact Deep Earth Academy
at [email protected]. The
respective core photographs are available
at:
http://www-odp.tamu.edu/
publications/208_IR/208TOC.HTM. Scroll
down and click on Images. Scroll to image
1262B15H.PDF.
http://publications.iodp.org/
proceedings/303_306/EXP_REPT/
CORES/IMAGES/. Scroll down to image
1308A6H.PDF.
http://www-odp.tamu.edu/
publications/171B_IR/IMAGES.HTM.
(Images: 1049A17X.PDF, 1049B8H.PDF).
Background
This activity focuses on the sediment
of the open ocean (as opposed to
continental margins). Along continental
margins a majority of the sediment found
is terrigenous—derived from pre-existing
rock. This type of sediment is eroded
from landmasses and transported to the
margins usually by water (e.g., rivers,
streams). Once it enters the ocean, this
sediment is rapidly deposited. Ice-rafted
debris is also terrigenous in origin, but its
mode of transport is much more unique
than rivers. As the name implies, icerafted debris is transported and deposited
by icebergs, ice floes and other forms
of floating ice associated with glacial
advance and retreat. The distribution of
ice-rafted debris is very limited, as it can
only occur where glaciers are found—in
polar regions. In tropical regions, the
dominant sediment type is biogenic—
produced by organisms. Finally, there is
the temperate region. The sediment found
in this region can vary as greatly as the
region’s climate conditions.
Climate and Sediment
What to do
investigations on the core replicas or photos,
allowing adequate time to examine each core
replica.
1. Set out core replicas at stations around the
room.
2. Ask your class to describe the climate found in
polar, temperate and tropical regions. Make a
chart on a board or flip chart.
5. When all the groups are finished, lead a class
discussion of their answers. In particular,
gather the class around each core replica to
look closely at its composition and discuss
what they see.
3. Once you have some answers up, ask students
to predict what type of sediment they would
expect to find in each area. Write these
predictions on your chart.
Submitted by
4. Hand out the student page and instruct
students to work in groups to complete the
Dr. Beth Christensen, Adelphi University and
Catherine Wiltsey, Adelphi University
TM
Teaching for Science • Learning for Life | www.oceanleadership.org
During ODP Leg 208, sedimentologists Zhifei Liu (China) and Susan Keller (USA) used surgical precision to microsample cores with sediments deposited during the Paleocene/Eocene Thermal Maximum.
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Climate and Sediment
Student Page
Background
this location? Now examine the core replica
or photograph of this area for Site 1262. What
types of sediment are present?
Climate is the long-term weather of a region. It
plays a big part in determining the type of sediment
found in an area. Earth is divided into three climate
zones: tropical, temperate and polar. The tropical
zone is the section of the planet centered on the
equator. It is bounded to the north by the Tropic of
Cancer and to the south by the Tropic of Capricorn.
The tropics extend from about 23° 30’ N through
the equator (0°) to 23°30’ S. Typically, the tropics
have a hot, moist climate.
5. Integrated Ocean Drilling Program (IODP)
Expedition 303 recovered cores from the North
Atlantic. What type of sediment would you
expect to find at this location? Now examine
the core replica of this area. What type of
sediment is present?
6. The core of Leg 171B shows the K/T boundary.
This core was recovered from the Blake
Plateau off the East Coast of the United States.
What type of sediment would you expect to
be present? Examine the core. What kind of
sediment do you observe?
There are two temperate zones, one in each
hemisphere. In the Northern Hemisphere, the
temperate zone extends from the Tropic of
Cancer to the Arctic Circle (66° 30’ N). The
southern temperate zone extends from the Tropic
of Capricorn to the Antarctic Circle (66° 30’ S).
Though there can be days or short
periods of extreme hot or cold
temperatures in the temperate
zone, the climate of this area is
typically mild. There is a subtle
progression through the four
seasons.
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Teaching for Science • Learning for Life | www.oceanleadership.org
Beyond the temperate zones lie the
polar regions. The northern polar
region is defined by the Arctic Circle
and the North Pole (90° N), while
the southern polar region is defined
by the Antarctic Circle and the
South Pole (90° S). Polar zones are
dominated by the polar ice caps.
Activities
Answer the following questions
using the attached sediment
distribution diagram. Think about the relationship
between climate and biology.
Further Exploration
As seen in the sediment distribution diagram,
sediment distribution changes as you move from
continental margins to the deep ocean. What types
of sediments are found on continental margins that
are not found in the open ocean? Why do you think
this happens?
1. Find the tropical zone on this map. What
types of sediments are present? What type
dominates? Why?
2. Find the temperate zone. What types of
sediments are present? What type dominates?
Why?
3. Find the polar region. What types of sediments
are present? What type dominates? Why?
4. Using the Ocean Drilling Program site location
map on this page, find the location of the drill
site for Leg 208 on the Walvis Ridge. What
type of sediment would you expect to find at
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Figure: Copyright 2005, The McGraw-Hill Companies, Inc. From “An Introduction to the World’s Oceans” (8th edition), K. Sverdrup, A. Duxbury, and A. Duxbury, Used with permission.
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Teaching for Science • Learning for Life | www.oceanleadership.org
Sediment Distribution in the World’s Oceans
Climate and Sediment
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