This section is excerpted from a discussion written by Dr. R. J. Stern.

The concept of the Subduction Factory (Fig. A-1) refers to the chemical processing that accompanies the subduction of oceanic mantle, crust, and sediments. This concept emphasizes the fluxes of material and energy in to and out of subduction zones, and the role that these processes play in shaping convergent plate boundaries, the deep mantle beyond, and the air and water above. Raw materials - seafloor sediments, oceanic crust, and mantle lithosphere - are fed into the Subduction Factory at deep-sea trenches. As subduction proceeds, this material is squeezed and heated, releasing fluids that carry a lot of dissolved chemicals. These fluids rise into the mantle wedge above the subduction zone, changing the composition of the mantle and sometimes causing it to melt. The products of the Subduction Factory include melts (magmas and their eruptive equivalents, lavas), aqueous fluids, metalliferous deposits, serpentine mud volcanoes, lavas, continental crust, gases, organic material, back-arc seafloor --emerge from the Factory on the upper plate. The remainder of the material that is processed in the Subduction Factory sinks deep into the mantle, someday to be resurrected as mantle plumes. The Subduction Factory is thus powerful but well-hidden. We can examine its raw materials and its products, but the machinery itself is obscured from view.

The Subduction Factory experiment (http://www.ldeo.columbia.edu/margins/SubFac.html) is part of the MARGINS Initiative (http://www.ldeo.columbia.edu/margins/Home.html) of the National Science Foundation (http://www.nsf.gov/). The Subduction Factory experiment aims to study fluxes through the subduction zone to address three fundamental science themes: 1) How do variables such as convergence rate and sediment thickness control the production of magma and fluid from the Subduction Factory? 2) How does the volatile cycle (H2O and CO2) impact chemical, physical and biological processes from trench to deep mantle? 3) What is the mass balance of chemical species and material across the Subduction Factory, and how does this balance affect growth and evolution of the continental crust?

The Subduction Factory experiment will proceed by focused scientific investigations on active subduction zones by geologists and geophysicists on land and at sea and in computer and chemistry labs all across the U.S. A wide range of field and laboratory studies measurements will be integrated at every level with physical and chemical models of how the Subduction Factory operates. Several other nations have also started or are considering launching their own ‘Subduction Factory’ experiment. Because there are over 30,000 km of convergent plate margins and subduction zones on Earth, it has been necessary to focus efforts to understand the Subduction Factory on two such systems. It has been decided that the Central American (Fig. A-2) and Izu-Bonin-Mariana (IBM; Fig. A-3) subduction systems will be the targets of this research effort. The teachers and other members of the ‘Subduction Crew’ aboard the Research Vessel (R/V) Melville will be studying the southern end of the IBM arc system.

Dr. Stern’s overview continues…

To find out basic information about what a subduction zone is, where these are found, and what makes them operate, please return to the home page and click on the "Geology" link.

What exactly is a "virtual field trip"?

As defined by Nix, 1999 in A Critical Evaluation of Science-related Virtual Field Trips available on the World Wide Web: "a virtual field trip is an inter-related collection of images, supporting text and/or other media, delivered electronically via the World Wide Web, in a format that can be professionally presented to relate the essence of a visit to a time or place. The virtual experience becomes a unique part of the participants' life experience".

Using the Virtual Field Trip in your Classroom

UTD Science/Mathematics Education Virtual Field Trips are designed for use in ANY and EVERY classroom. Although the main topics are based in ecology (life science), geology (earth science) and man (environmental science), this site also supports lessons in computer science, technology, mathematics, physics, social studies, geography, history, language arts and classical art. The structure is open so that you may approach most any topic from virtually every direction. Each "element" is woven into the "Big Picture" with links and references to allow you and your students to explore the presented information through the most logical route. The same scientific principles and processes apply in other geographic locations as well!

This site simply provides a framework to offer a sense of the real-world setting to those who are unable to or planning to visit the focus area to see for themselves. We’ve included some links to external sources to supplement our original content (and hope that they are all active). Search the web, library or other resources for more information and ideas on how to use this site.

Please send a message to SciMathEd@utdallas.edu!

Click here to find out more about "Chunking" complex concepts to manage information and assess understanding.

Sorry for the lousy graphics. There's a lot of ancillary detail in the diagrams. Don't worry about what each "box" actually says. This is simply an example. The point is to get the idea of how it all fits together. This is NOT the ideal presentation, but it's a start that will hopefully help you get started!

Inquiry supports learning by suggesting that students design and carry out activities to answer their own questions. This teaching technique is dependent on the experience of the teacher in dealing with this type of learning and on the experience of the students with an inquiry learning environment. Students generating their own questions and performing their own labs is not an automatic occurrence. It is a technique that must be taught to the students and teachers alike.

Find out more in Levels of Inquiry, an article by Cynthia E. Ledbetter.

If you’re thinking about using concept maps for project development, take a look at this

Web Site Contribution Evaluation Rubric

Please feel free to use this Melville Research Cruise questionnaire as a pre-/post-test instrument.

Other options include electronic portfolios, concept maps, and reflective journals...

Find out more by exploring these sites:

Alternative Modes of Teaching and Learning

The Centre for Educational Technology
Integrating the Internet into Your Classroom
Assessment Practices and Students Knowledge Profiles in a Problem-based Curriculum
Classroom Learning Environments and Students' Approaches to Learning