Geology

Self-Organizing Seismic Field Assignment Using the EG&G Smartseis
Due Monday, November 6th (2006)- but don't put it off too long!

I want each of you, in self-selecting groups of 3-4, to take out the seismic refraction equipment and complete an experiment of your own design. You can run a few perpendicular lines where we did the class lines or go somewhere else. Collect enough data so that everybody in your group gets a chance to learn the instrument. In the past, it has proven most successful to go somewhere where the near-surface is not complicated by a bunch of bulldozer work. Thus, soccer fields and the like often produce complications from near-surface, low velocity layers with undulating thicknesses.

There are a number of questions around which you can structure your experiment, but in general you want to define an experiment where you will get good results:

can you find a place with alluvium over Precambrian bedrock and produce good two-layer results?
how deep is groundwater and bedrock at the park north of Lincolnwood (I think you can get three layers there if you go north of the road a little bit)
can you measure the water table somewhere where you know/suspect it is shallow (<10 meters)?
can you measure the thickness of the near-surface fill and bullldozer refuse where we did the equipment demo?
can you determine the location of a known subsurface feature (foundation, septic tank, underground storage tank) by measuring a fan of lines where some cross it and others don't?

Although it is most efficient to do the field work in small groups, each individual must analyze thier own data and turn in their own report (up to three pages not including figures and map) to be graded. Check out the web page on reports and field notes but in general you'll want this sort of outline:

Introduction/Problem
Experimental Design and why you chose it given local observations
Results
Interpretation & Conclusion

Include a map showing your field setup, plots of your results, and possibly a figure showing your interpretation. For the latter you might use an isopach map or fence diagram. I robbed these figures off the web as examples to give you an idea and jog your memories from stratigraphy and/or structure courses!

You will have to self-organize into groups. Designate a leader and set a time for your field work; if necessary we'll sort out the times in class to make sure there is no overlap in desired use times. You can check out a key to the lab from Loreene or make arrangements with me. Be extremely careful and responsible with the equipment.

Due Monday, November 6th - don't put it off too long because you'll need time for the magnetic project as well.

Geosciences Department - The University of Montana - 32 Campus Drive #1296 - Missoula, MT 59812-1296
Phone: (406) 243-2341 Fax: (406) 243-4028 Email: geology@mso.umt.edu

The University of Montana Geosciences Department