As the accuracy of GPS estimates of site position continues to improve the detection of smaller geophysical signals becomes possible. The capability of GPS for detecting short-term transient motions such as the minute motions caused by surface waves of seismic origin will be assessed.

Make GPS measurements with a GPS antenna on a moving platform. The antenna will experience accelerations of up to cm/s2 level for a period of several minutes while recording GPS data simultaneously. A second stationary antenna at a distance of several meters will also be simultaneously recording GPS data. This GPS campaign should be run during the Spring of 2005; it will last about a month.