Where is the carbonate on Mars?
In-Class Activity 2_Water World
Julia Kahmann-Robinson PhD and Marjorie Chan PhD, University of Utah Department of Geology & Geophysics
Expose students to the carbon cycle on Earth and how carbonate rocks are created. Students will develop a line of evidence or explanation for the reasons why carbonate rocks are not abundant on Mars.
- Depending on your mode of delivery (in class versus perhaps a homework setting), load the Image File .ppt for the class and make sure you have an Internet connection to view the associated videos.
- Find 3 specimens of carbonate rocks (micrite, coquina, grainstone/packstone, or chalk) or use Image File to show 3 specimens of carbonate rocks.
- Have JMARS available to view carbonate minerals maps of Mars, as well as MOLA maps for geographic context (see Image file in Resources of module shell).
Have students observe 3 different carbonate rocks and ask the following:
- What are the similarities between these rocks?
- Where might these rocks have been deposited and form? What is your evidence?
Forming carbonate rocks on Earth
- Have students brainstorm how carbonate rocks are formed. Write their ideas on the board.
- Watch the following NASA video entitled "Keeping up with Carbon": http://www.youtube.com/watch?v=FgEZpX3n5mo
- How does the student's "formation" history compare/contrast with the video?
- What elements of the video's content exist/do not exist on Mars?
Carbonate rocks on Mars
- Bring up JMARS maps of carbonate rocks for students to view the extent (or lack thereof) of carbonate rocks.
- Where are the carbonate minerals most common?
Carbonates – a class of sedimentary rocks composed primarily of carbonate minerals ranging from calcite to dolomite.
Assign to students:
Consider the biosphere, lithosphere, and current atmospheric conditions of Mars at present, when responding to the following questions:
- What would students need to change about Mars today for Mars to be conducive to carbonate development?
*Note: Answers can be elaborately crazy, i.e. put petroleum-powered cars on Mars and create vast amounts of CO2 emissions or if possible move Mars closer to the sun so that it isn't so cold....etc.
Present the above image of the Nili Fossae region of Mars (for a full resolution image see the Image File for this module) and ask students the following questions:
In this hypothetical situation (although real imagery)
- Where might you find carbonates?
- On what information did you base your answer?
- What is the basis for their decision? [any water environment might have the potential]