GPS stands for Global Positioning System. This is a geophysical technique used to accurately determine the locations of specific points in three dimensions. Very small (mm scale) changes in the locations of these points can be recorded over time
Jan Lindsay, Jerome David, John Shepherd and Judith Ephraim, Volcanic Hazard Assessment for Saint Lucia, Lesser Antilles, Glossary Of Terms Used In This Report, Seismic Research Unit The University of the West Indies St. Augustine Trinidad and Tobago 2002. file:///C:/Users/user/Downloads/1001.pdf, (ND/ Volc Emr - Brit) {963}