Suggested Pacific Plate Distortion Experiments

Abstract

The reasons for investigating possible time-dependent visco-elastic distortions in the Pacific plate and possible associated variations in its motion with respect to North America will be discussed. Such distortions could be important in large and rapidly moving plates, and may provide information on the properties of the underlying aesthenosphere. Plate distortion information also is needed in order to interpret changes with time in the Haleakala-McDonald baseline in terms of relative plate motions. Experiments are suggested which could be done by the University of Texas transportable lunar ranging station after it completes its initial tasks, which are determining the station location measurement accuracy and investigating the basic stability of well-separated points on the North American plate. The first priority for Pacific plate experiments would be measurements at locations which are several thousand km from Haleakala, are well away from plate boundaries, and have major airports. U.S. measurements at Wake Island and joint measurements with the French in Tahiti appear to be desirable.