Chemistry of continental vs. oceanic rocks

Andrew Goodwillie, Kim Kastens, Linda Sohl, Jaime Toro, Amy Cline, Shelley Olds, Rob Graziano, Sarah Titus, Erin Heffron, Chuck Anderson, Jim Washburn, Steve Reynolds, Ron Schott, Charlie Onasch
Topic: petrology, geochemistry
Course Type: intro or upper level

Description

Students use data from PetdB to plot the chemistry of rocks samples collected from both the ocean floor and continental locations.

Goals

Students get to see how various elements (e.g., Mg, Si) vary with continent vs. oceanic crust. Continents are highly variable and more siliceous, and less mafic. Oceans are more uniform, less siliceous and more mafic.

Assessment

Students would be able to identify probable chemistry given information about sample location.

References

See http://www.ldeo.columbia.edu/~kastens/curriculum/conceptests/index.html
(specifically, the section on rock type on mid-ocean ridge)