New Zealand - Southern Alps

New Zealand GPS

Supported by NSF’s Instruments and Facilities and Theoretical and Experimental Geophysics Programs

Collaborators (recent past and present)

• John Beavan and Deion Matheson, Institute of Geological and Nuclear Sciences, Lower Hutt, New Zealand
• Paul Denys and Mike Denham, Department of Surveying, Otago University, Dunedin, New Zealand
• Brad Hager and Tom Herring, Department of Earth, Atmospheric, and Planetary Sciences, MIT

In early 2000 we installed a GPS network consisting partly of continuously recording receivers and temporary receivers that recorded 3-6 months during the austral summer (Figure 1). Our goal is to measure accurately vertical movement across the Southern Alps, a region where rock rises especially rapidly with respect to sea level largely in response to the very rapid erosion of the western flank of the Southern Alps. Preliminary results [Beavan et al. 2004] show that the vertical component of movement increases from a low value on the west coast to a maximum ~10 km from the Alpine fault, which bounds the Southern Alps on its western flank, and then decreases eastward again.

References

Beavan, J., D. Matheson, P. Denys, M. Denham, T. Herring, B. Hager, and P. Molnar (2004), A vertical deformation profile across the Southern Alps, New Zealand, from 3.5 years of continuous GPS data, Proceedings of the Workshop: The state of GPS vertical positioning precision: Separation of earth processes by space geodesy, ed. by T. van Dam and O. Francis, Cahiers de Centre Européen de Géodynamique et Séismologie, vol. 23, Luxembourg, 111-123.