Richard G. Gordon
William M. Keck Professor

Research:

Geophysics - tectonics, tectonophysics, marine geophysics, space geodesy, paleomagnetism

Quantitative Tectonics: Applications to regional and global tectonics of investigations of the horizontal kinematics of the crust and lithosphere inferred mainly from marine-geophysical, paleomagnetic, space geodetic, and earthquake-mechanism data.

Tectonic applications of space geodesy: Donald Argus and I are studying the motion between the Pacific, North America, Eurasian, and Sierra-Nevada plates over the past decade using geodetic data from very long baseline interferometry. One focus has been how motion is accommodated across the wide deforming zone in western North America that divides the Pacific from the North American plate.

Plate rigidity and wide plate boundary zones: Using marine geophysical and space geodetic data, students, colleagues and I have been placing quantitative limits on plate rigidity and identifying regions of the world where plates deform over very wide zones, which we interpret as diffuse plate boundaries. Of particular interest has been the deforming zone in the equatorial Indian Ocean east of the Central Indian Ridge and west of Sumatra. Our recent work has expanded to include the motion between the Capricorn and Australian plates and the oceanic portions of the Nubian and Somalian plates.

Tectonic paleomagnetism: With Ben Horner-Johnson, I am analyzing the shapes of sea-surface magnetic anomalies due to seafloor spreading. From this information we estimate paleomagnetic poles averaged over small, precisely dated time intervals. Goals of this work include testing circum-Pacific plate reconstructions, determining the history of motion of hotspots relative to the paleomagnetic axis, and to put bounds on possible persistent quadrupole components of the geomagnetic field in the past.

Plate motion relative to the hotspots: Current studies include a global model of current plate motion relative to the hotspots (with Alice Gripp), a model for the Tertiary and Cretaceous motion of the Pacific plate relative to hotspots, implications for the tectonic and volcanic evolution of the Pacific, the quantification of uncertainties of plate motion relative to the hotspots, and tests for motion between hotspots.

Selected Publications

Zatman, S., R. G. Gordon, and M. A. Richards, "Analytic models for the dynamics of diffuse oceanic plate boundaries," Geophysical Journal International, 145 (2001): 145-156.

Gordon, R. G., "Diffuse oceanic plate boundaries: Strain rates, vertically averaged rheology, and comparisons with narrow plate boundaries and stable plate interiors ," in Richards, M. A., R. G. Gordon, and R. D. Van der Hilst (editors), History and Dynamics of Global Plate Motions, Geophysical Monograph 121, American Geophysical Union, Washington, DC, (2000): 143-159.

Richards, M. A., R. G. Gordon, and R. D. Van der Hilst, "Plate tectonics and mantle convection: thirty years later," in Richards, M. A., R. G. Gordon, and R. D. Van der Hilst (editors), History and Dynamics of Global Plate Motions, Geophysical Monograph 121, American Geophysical Union, Washington, DC, (2000): 1-4.

Gordon, R. G., "The Antarctic connection," Nature, 404 (2000): 139-140.

Kirkwood, B. H., J.-Y. Royer, T. C. Chang, and R. G. Gordon, "Statistical tools for estimating and combining finite rotations and their uncertainties," Geophysical Journal International, 137 (1999): 408-428.

Chu, D., and R. G. Gordon, "Evidence for motion between Nubia and Somalia along the Southwest Indian Ridge," Nature, 398 (1999): 64-67.

Petronotis, K. E., and R. G. Gordon, "A Maastrichtian palaeomagnetic pole for the Pacific plate from a skewness analysis of marine magnetic anomaly 32," Geophysical Journal International, 139 (1999): 227-247.

Gordon, R. G., "The plate tectonic approximation: Plate nonrigidity, diffuse plate boundaries, and global plate reconstructions," Annual Reviews of Earth and Planetary Sciences, 26 (1998): 615-642.

Chu, D., and Gordon, R.G., "Current plate motions across the Red Sea," Geophysical Journal International, 135 (1998): 313-328.

Richards, M. A., R. G. Gordon, and R. D. Van der Hilst (editors), History and Dynamics of Global Plate Motions, American Geophysical Union, Washington DC (2000), pp. 398. Geophysical Monograph 121.

Pending Publications

Gripp, A. E., and R. G. Gordon, "Young tracks of hotspots and current plate velocities," Geophysical Journal International, (in press).

DeMets, C., R. G. Gordon, and J.-Y. Royer, "New high-resolution estimates of the relative motion between the Indian, Capricorn, and Somalian plates since 20 Ma: Evidence for changes coinciding with the onset of seafloor deformation in the Central Indian basin," Geophysical Journal International, (in revision).