ODM2 Variable Name Controlled Vocabulary ODM2 Working Group A vocabulary for describing the name of Variables. Seismic refraction Seismic refraction is a geophysical principle (see refraction) governed by Snell's Law. Used in the fields of engineering geology, geotechnical engineering and exploration geophysics, seismic refraction traverses (seismic lines) are performed using a seismograph(s) and/or geophone(s), in an array and an energy source. Wikipedia https://en.wikipedia.org/wiki/Seismic_refraction Added to support Critical Zone Observatory (CZO) data use cases.