|
Oceanography
Lesson 2: Sea Floor
Mapping (Sounding Out the Sea Floor)Grade Level: 8th
Subjects: Science
and Math
Learner Outcomes:
- Realize that ocean
floor is as varied topographically as land surface.
- Understand that
more data means greater accuracy.
- Recognize and define
undersea geological formations.
- Utilize measurements
to create profile and topographic representations of areas which can not
be inspected visually.
Duration of Lesson: 1-3 45 minute class periods
Materials per group:
- Sea floor box (see
teacher notes)
- Depth gauge (Ka-bob
skewer or long broom straw marked in centimeter increments)
- Graph paper or
unlined typing paper
- Ruler
- Colored pencils
Technology Tools/Courseware:
- Graphing calculator
(optional)
- Computer with internet
connection (optional)
- 3-D Graphing Software
(optional)
- Computer printer,
preferably color (optional)
Teacher Notes:
- Use duplicator
paper boxes with tops.
- Shape underwater
formations from sections of 4' X 8' X 1" styrofoam sheet layered, glued and
cut into required forms).
- Place 4 or 5 formations
in each group's box. I recommend using different patterns and combinations
of formations in each box.
- If the boxes are
made up ahead of class, tape the tops closed before they are given out.
- When marking the
depth gauge skewers, if every 5th mark is a different color it will facilitate
reading the depths quickly and more accurately.
- Mark the entire
box top with in one inch grids and punch a SMALL hole at every intersecting
line. These will serve as the locations where readings on the depth
gauge will be made. Holes should be just big enough for the depth gauge
to easily pass through but not large enough for students to see into the
box.
Procedures:
Part 1: Sea Floor
Profile
- Take depth readings
at 3 locations along one line of the grid. (I recommend along the mid line
of the box, with the first reading in the first hole, the second reading
in the center, and the third reading in the last hole of the mid line.)
- Translate the readings
from the depth gauge into ocean depths using 1 cm = 100 meters. (This scale
can easily be modified to better suit different types of boxes.)
- Design a graph
and enter the 3 readings at appropriate places. (Maximum depth shown on
the graph should correspond to the possible depth of the box)
- Connect the 3 points
to form a profile map of the bottom at that line of the grid. Describe
the shape of the sea floor using only the data from the 3 points.
Make inferences as to the true shape of the bottom according to the available
data. Hypothesize as to the accuracy of the inference and decide how to
increase accuracy.
- Using the same
profile graph, record the depths from every point along that same line.
Using a different color, connect the points now available to form a new
picture of the sea floor profile along that single line.
- Compare and contrast
the results of the two profiles. Recognize and explain the importance of
obtaining as much data as possible before drawing conclusions.
- There is excellent
3-D graphing software that can be purchased but most is so expensive that
it is prohibitive for use in one single science unit. The best I have found
is from Gamma Design Software. The cost for one computer is $499
and includes a 200 page user manual, maintenance updates via web download,
technical support via email. A classroom or single building license
is $1500. This is a software that could easily be used for other
science units and could be adapted for use by other subjects as well (math
graphing, social studies for such things as population studies or natural
resource productivity, etc.) so perhaps the software as well as the cost
could be shared by several departments.
Part 2: Sea Floor
Mapping
- Use the depth
gauge to measure the depths of any 15 selected points and record these
on a graph.
- Attempt to
use these to construct a topo map of the sea floor.
- Take an additional
15 readings to add to the graph.
- Use these
additional data to revise the graph. (In a different color)
- Continue
to add groups of data and revise the graph until all possible depths have
been measured and recorded.
- After recording
all the points, connect them to form a topo map.
- Make a key
using different colors to represent each depth increment and color the
graph accordingly.
- Use the topo
map to identify each of the structures represented.
- Plot the
data using graphing software and compare the results to the handmade maps
Modifications:
- Have each group
make their own sea floor box then switch with another group.
- This same set up
can be used for exploring coastal formations, topo mapping of land surfaces
etc.
- Have each group
make their own "depth gauge" by marking the skewers in centimeters.
- To save time, have
the graphs already made up for the profile maps and the topo maps.
- Have students make
a profile along every line and then overlay them to form the topo map.
Enrichment Activities:
- Have a student
or groups of students research each type of undersea formation and how
it was formed geologically and report their findings to the class.
- Obtain an actual
sea floor profile map of part of the Atlantic and have students create
a model using the data from that profile.
- Use the 3-D graphing
software to create computer images of the sea floor and compare those to
the maps made by the students.
Evaluation/Assessment:
Subjective:
- Observation
- Informal questions
- Class and group
discussion
Objective:
- Test on terminology
and concepts
- Grade the graphs
and maps by using a rubric
West
Virginia State Instructional Goals and Objectives:
Science/Math: 81. 8.2, 8.4, 8.5,
8.6, 8.7, 8.8, 8.9, 8.10, 8.11. 8.12, 8.13, 8.14, 8.15, 8.16, 8.17, 8.18,
8.19, 8.20, 8.21, 8.22, 8.23, 8.24, 8.25, 8.60, 8.66, 8.72, 8.78, 8.82,
8.88, 8.89 8.13, 8.18, 8.27, 8.30, 8.40, 8.44, 8.57, 8.58
National
Standards:
Science:
- Understands Earth's
composition and structure
- Knows that
the Earth is comprised of layers including a core, mantle, lithosphere,
hydrosphere, and atmosphere
- Knows how
land forms are created through a combination of constructive and destructive
forces (e.g., constructive forces such as crustal deformation, volcanic
eruptions, and deposition of sediment; destructive forces such as weathering
and erosion).
- Understands the nature
of scientific knowledge
- Understands
the nature of scientific explanations (e.g., use of logically consistent
arguments; emphasis on evidence; use of scientific principles, models and
theories; acceptance or displacement of explanations based on new scientific
evidence)
- Understands the nature
of scientific inquiry
- Knows that
there is no fixed procedure called "the scientific method," but that investigations
involve systematic observations, carefully collected, relevant evidence,
logical reasoning, and some imagination in developing hypotheses and explanations
- Designs and
conducts a scientific investigation (e.g., formulates hypotheses, designs
and executes investigations, interprets data, synthesizes evidence into
explanations, proposes alternative explanations for observations, critiques
explanations and procedures)
- Knows that
observations can be affected by bias (e.g., strong beliefs about what should
happen in particular circumstances can prevent the detection of other results)
- Establishes
relationships based on evidence and logical argument (e.g., provides causes
for effects)
Math:
-
Uses a variety of
strategies in the problem-solving process
- Represents problem
situations in and translates among oral, written, concrete, pictorial,
and graphical forms
- Generalizes from
a pattern of observations made in particular cases, makes conjectures,
and provides supporting arguments for these conjectures (i.e., uses inductive
reasoning)
- Uses a variety of
reasoning processes ( e.g., reasoning from a counter example, using proportionality)
to model and to solve problems
- Understands and applies
basic and advanced properties of the concepts of measurement
- Selects and
uses appropriate units and tools, depending on degree of accuracy required,
to find measurements for real-world problems
- Understands the general
nature and uses of mathematics
- Understands that
mathematics has been helpful in practical ways for many centuries
- Understands that
mathematicians often represent real things using abstract ideas like numbers
or lines: they then work with these abstractions to learn about the things
they represent
Job/Career Clusters:
- Science/Natural Resources
- Engineering/Technical
References:
Authors: Bryan
Barnett, Pat
Ryan and Judy
Staats
|