1 Introduction
2 Signal Basics
3 Subsurface Properties and Propagation
 3.1 Stones in the Pathway
  3.1.1 Permittivity
  3.1.2 Conductance
  3.1.3 Propagation in Lossy Material
 3.2 Reflection Coefficient
  3.2.1 Reflection at a planar interface
  3.2.2 Reflection from a slab
 3.3 Illustrating the Point
 3.4 Free Modes of Decay
  3.4.1 Free Mode Eigenfrequencies by Newton Root Search
  3.4.2 Free Mode Eigenfrequencies by Contour Integration
  3.4.3 Summary
4 Conclusion
A Appendix: Maxwell’s Equations