Indonesia GPS 1991-1997
Since 1989 we have been monitoring crustal motion throughout Indonesia
with Scripps Inst. of Oceanography and BAKOSURTANAL using the Global Positioning
RPI: Rob McCaffrey, Colleen Stevens, Peter Zwick
Scripps: Yehuda Bock, Jeff Genrich, Linette Prawirodirdjo
BAKOSURTANAL: Jakub Rais, Cecep Subarya, Toto Puntodewo
Among the important discoveries to date are as follow:
The Banda arc in the vicinity of Timor is now moving with Australia - it
has been accreted to the Australian margin (see
A large part of the Bird's Head of New Guinea is moving with the Pacific
plate while SE Irian Jaya moves with Australia (see
map) - hence, there must be a large rapid (80 mm/yr) shear zone separating the Bird's
Head from Irian Jaya.
- Slip and strain partitioning in Sumatra is clear in the GPS results and consistent with inferences drawn from slip vector orientations.
Puntodewo, S.S.O., R. McCaffrey, E. Calais, Y. Bock, J. Rais, C. Subarya,
R. Poewariardi, C. Stevens, Fauzi, J. Genrich, and P. Zwick, GPS measurements
of crustal deformation within the Pacific-Australia plate boundary zone
in Irian Jaya, Indonesia, Tectonophysics 237, 141-153, 1994.
Genrich, J., Y. Bock, R. McCaffrey, E. Calais, C. Stevens, and C. Subarya,
Accretion of the southern Banda arc to the Australian plate margin determined
by Global Positioning System measurements, Tectonics, 15,
McCaffrey, R., Slip partitioning at convergent plate boundaries of SE Asia,
in Tectonic Evolution of SE Asia Symposium, Geol. Soc. Special Publication
No. 106, 3-18, 1996.
Prawirodirdjo, L., Y. Bock, R. McCaffrey, J. Genrich, E. Calais, C. Stevens,
S. S. O. Puntodewo, C. Subarya, and J. Rais, Geodetic observations of interseismic
strain segmentation at the Sumatra subduction zone, Geophysical Research Letters, 2601-2604, 1997.
Stevens, C., R. McCaffrey, E. Silver, Z. Sombo, P. English, and J. van
der Kevie, Mid-crustal detachment and ramp faulting in the Markham Valley,
Papua New Guinea, Geology, 26, 847-850, 1998.
Stevens, C., R. McCaffrey, Y. Bock, J. Genrich, C. Vigny,
C. Subarya, S.S.O. Puntodewo, and Fauzi, GPS evidence for rapid rotations
about a vertical axis in a collisional setting: the Palu fault of Sulawesi,
Indonesia, Geophysical Research Letters, 26, 2677-2680, 1999.
McCaffrey, R., P. Zwick, Y. Bock, L. Prawirodirdjo, J. Genrich, C. W. Stevens,
S. S. O. Puntodewo, and C. Subarya, Strain partitioning during oblique
plate convergence in northern Sumatra: Geodetic and seismologic constraints and numerical
modeling, Journal of Geophysical Research, 105, 28,363-28,376, 2000.
Genrich, J.F., Y. Bock, R. McCaffrey, L. Prawirodirdjo, C.W. Stevens, S.S.O. Puntodewo, C. Subarya, and S. Wdowinski,
Distribution of slip at the northern Sumatra fault System, Journal of Geophysical Research, 105, 28,327-28,341, 2000. (PDF reprint)
Stevens, C. W., R. McCaffrey, Y. Bock, J. F. Genrich, M. Pubellier, and C. Subarya, Evidence for Block Rotations and Basal Shear in the World's Fastest Slipping Continental Shear Zone in NW New Guinea, AGU volume on Plate Boundary Processes, S. Stein and J. Freymueller, editors, in press, 2002. ( PDF )
Link to UNAVCO for descriptions
of other GPS projects.
This work is supported by the National Science Foundation.