Gas Blowout Workshop Lesson Plan:

"Mapping the Unseen Floors"

Created by Jeffrey Leben, Kevin Drantch, and Jeffrey Williams

NOTE:  THIS LESSON SHOULD BE USED IN CONJUNCTION WITH MATERIALS FROM  THE GAS BLOWOUT EXPLORATION AT THE LAMONT-DOHERTY EARTH OBSERVATORY IN JULY 2004. THE PROGRAM WAS SPONSORED BY THE EARTH2CLASSWORKSHOPS FOR TEACHERS AND NSF COLLABORATVE RESEARCH GRANT 0242426.

AIM:

          How can we use instruments to create a topographic map of the sea floor? (Suggested duration of lesson: 2-4 days)

VOCABULARY WORDS:

          acoustic                           anomaly                  autonomous            
          bathymetric                       beam                      chirp

          concentration                    continental shelf       hydrate

          legacy                              methane                 multi-beam
          resolution                          sonar                     stratigraphy
          submersible                       swath                     topography

        "Non-science words":            legacy

LESSON PREVIEW:

          Almost 70% of the Earth’s surface is covered by water.  How can scientists learn the appearance of the ocean floor?

INTRODUCTORY LESSON:

1.      The teacher will review with the class the components of topographic and other maps.

2.      The teacher will demonstrate that the ocean floor contains a variety of features, some similar to landforms on the continents.

3.      The teacher will compare the effect of geologic occurrences such as earthquakes, avalanches, and volcanoes to events occurring on the ocean floor.

4.      The teacher will explain the need to assess and understand the impact of these events.

TOPIC POINT:

          How can we know where these landforms are located on the ocean floor?

GROUP RESEARCH ACTIVITY:

          Student groups will engage in a WebQuest seeking to identify and understand the purpose of the research instruments named below and answer the investigative questions. Each group will prepare a written report on one of the instruments searched, using visual and/or computer-based displays.

          Student groups present their findings to the entire class.

Research Instruments:

1.        Multi-Beam and Single-Beam SONAR

2.        Side-Scan Sonar

3.        Autonomous Underwater Vehicle

Investigative Questions:

1.        What is the purpose of each instrument and what information

     does it provide?

2.        How is it used to reveal the topography?

3.        Can it be used by itself or does it need to be used in conjunction with other instruments?  Why or why not?

4.        Make a simple labeled drawing of the instrument.

WebQuest:

All research should begin at the home page for the website:  http://www.oceanexplorer.noaa.gov

Multi-Beam and Single-Beam SONAR

1.        Start at the home page for oceanexplorer.noaa.gov

2.        Find and click on “explorations”

3.        Find and click on “year 2001”

4.        Scroll to and click on “Continuing the Lewis and Clark legacy”

5.        Scroll to and click on “sea floor mapping”

6.        Click on the image (larger view)

7.        Read the explanation and answer the questions

Side-Scan SONAR

8.        Start at the home page for oceanexplorer.noaa.gov/

9.        Find and click on “observation tools”

10.    Find and click on “sonar systems”

11.    Scroll to and click on “side scan and multi beam sonar”

12.    Read the explanation and answer the questions

Autonomous Underwater Vehicle

13.    Start at the home page for oceanexplorer.noaa.gov/

14.    Find and click on “technology”

15.    Find (right side of page) and click on “submersibles”

16.    Scroll to and click on “AUVABE”

17.    Read the item “The Hardest Worker on Board”

18.    Answer questions 1, 2, and 4 plus the following:

What instruments would you include on the autonomous underwater vehicle and why?

You can find additional information on this topic through a DLESE (Digital Library for Earth Systems Education) search at http://www.dlese.org.

EXTENSION:

          The scientists usually still have unanswered questions and concerns following their exploration.  This is typical of the scientific discovery process.  This is one such question proposed by Dr. Jeffrey Weissel, the lead scientist of the LDEO team, has unanswered:

          “What should we look for on the sea floor to identify sites of active methane gas venting?”

          Based on your group’s WebQuest investigation, compose a letter to Dr. Weissel suggesting what instruments his team should include on the ATV to help them answer this question.

NOTE: Interested teachers may contact the Earth2ClassTeam (michael@earth2class.org) for directions about forwarding the letters to Dr. Weissel.