Module Overview for Instructors

Locating Subsurface Features using Gravity and Magnetics

Module Goals

  1. Students will explore how density variations in the subsurface allow the imaging of buried structures using gravity.
  2. Students will interpret magnetic data to detect hazards and infrastructure.
  3. Students will apply gravity and magnetics principles to interpret real-world data sets.

Assessment: Assessment of student learning can be approached flexibly. Each unit of the module includes student handouts and exercises that can be used for formative assessments. Learn more about assessing student learning in this module.

Outline

The module covers material sequentially, but the units can also often be taught as stand-alone lessons.

Unit 1: Locating Buried Objects Using Gravity

This in-class/lab/homework activity introduces students to the idea that the gravitational acceleration g varies across the surface of the earth and is sensitive to buried features. Students are asked to "read" and and run interactive animations of Newton's Law to understand how measured gravity profiles are sensitive to the mass and depth of buried objects.

Unit 2: Environmental Magnetism

This module introduces students to the underlying principles of magnetism. Students are introduced to major concepts on magnetism through a narrated video  and concepts are reinforced through a worksheet that allows the student to simulate changes in the magnetic fields around two magnets and to explore properties of the Earth's magnetic field as a function of position. Students then explore the significance of a magnetic dataset acquired as part of an archaeological survey .

Unit 3: Gravity and Magnetics Field Data Exercises

This activity focuses on practical application of concepts discussed in Units 1 & 2 through the analysis of measured or provided field datasets. Students will follow experimental procedures to measure gravity changes inside a building and/or analyze magnetic prospecting data. Students will gain the ability to interpret real datasets, justify their findings, describe limitations of the measurements, and produce graphics to communicate their data.

Making the Module Work

To adapt all or part of this module for your classroom you may also want to read through Using IGUaNA Modules for Your Course.