QUANTITATIVE ANALYSIS OF DATA IN AN INTRODUCTORY GEOHAZARDS COURSE

We present three activities designed to improve quantitative literacy in a non-major's geohazards course. Students analyze real data and its implications, including such concepts as error analysis, determination of significance and outliers. They also use their analysis to examine societal/policy issues.

The first activity utilizes data from North Cove, Washington, where coastline retreat has exceeded 4 kilometers in 130 years, causing the destruction of numerous residences. Students use shoreline maps, topographic maps, and oblique and vertical aerial photos to determine shoreline position and determine retreat rates over a variety of time scales. Students examine the variance in retreat rate, predict a current shoreline location, and match their prediction against the actual location. Finally, they propose a development limit and explore how confident they are in their determination.

In the second activity, students use historical data of small earthquakes and the Gutenburg-Richter relationship to estimate the recurrence interval of rare, large earthquakes. Students examine the limitations of sampling and outliers, and compare the results of this technique with paleoseismology results. They then address the public policy implications of their results. This activity is designed for the Pacific Northwest, but could be altered for other areas.

The third activity guides students to discover how we know about the interior of the Earth. Students first model P-waves traveling through a homogenous Earth and compare the results to measured arrival times. They then develop a 2 layered model and graphically determine a travel time curve. Finally, they use a publicly available web program to model as many layers as they wish. This inquiry-based activity shows one of the ways geologists learn about the inaccessible interior of Earth.

Each of these activities helps us meet the general outcomes of the geohazards course by helping students critically and quantitatively analyze data, generate hypotheses, test those hypotheses, generate conclusions and examine the implications and limitations of their analysis.