Cynthia Fadem

Earlham College

GEOS 316 Geochemistry: mid-level course for majors

lab safety, thermodynamics and kinetics, rock & mineral chemistry (Many students in this class had already taken Soils as well.)

part 1 of 2

basic reagent mixing, soil biophysical analysis, data representation (visual)

data representation (Follow-up lab included critical analysis, comparison, and combination of the datasets collected here.)

working in & among groups (i.e., organization of space among multiple groups with mutually exclusive goals)

Students conduct a geochemical analysis of a soil. Each group chooses one of the following analyses: conductivity buffer solution, conductivity, acidity, mineralogy, grain size, or loss on ignition. As this lab falls somewhere between the middle and end of the course, students are versed in various chemical methods. This lab reinforces those skills while forcing students to organize their time and be patient with each other while conducting careful lab science. The samples used for this lab were from a Bronze-Age archaeological site in Kazakhstan, but any samples could be substituted. To encourage free-thinking concerning their representations (and interpretations in the follow-up lab), as little background information as possible was given.

For this lab, a student's engagement with the chosen activity (and the ensuing data) and willing cooperation with their classmates were the most important factors. All (9) of the students did well on this lab (possibly owing to the particular orientation of this group of students to lab activity), but a few lagged in the follow-up analysis lab.