Showing papers by "Sean C. Solomon published in 2005"
Carnegie Institution for Science1, California Institute of Technology2, University of California, Los Angeles3, Jet Propulsion Laboratory4, United States Geological Survey5, Washington University in St. Louis6, Goddard Space Flight Center7, Case Western Reserve University8, Brown University9, University of Colorado Boulder10, University of California, San Diego11, Lunar and Planetary Institute12, Massachusetts Institute of Technology13
TL;DR: Mars was most active during its first billion years, and the Tharsis province became a focus for volcanism, deformation, and outgassing of water and carbon dioxide in quantities possibly sufficient to induce episodes of climate warming.
Abstract: Mars was most active during its first billion years. The core, mantle, and crust formed within ∼50 million years of solar system formation. A magnetic dynamo in a convecting fluid core magnetized the crust, and the global field shielded a more massive early atmosphere against solar wind stripping. The Tharsis province became a focus for volcanism, deformation, and outgassing of water and carbon dioxide in quantities possibly sufficient to induce episodes of climate warming. Surficial and near-surface water contributed to regionally extensive erosion, sediment transport, and chemical alteration. Deep hydrothermal circulation accelerated crustal cooling, preserved variations in crustal thickness, and modified patterns of crustal magnetization.
291 citations
TL;DR: In the Galapagos archipelago, shear-wave splitting measurements in this article show a rapid change from consistently oriented anisotropic to no measurable anisotropy.
Abstract: Shear-wave splitting measurements in the Galapagos archipelago show a rapid change from consistently oriented anisotropy to no measurable anisotropy. At the western edge of the archipelago delay times are 0.4– 0.9 s and fast polarization directions are 81– 109°E. These directions are consistent with anisotropy resulting from shear of the asthenosphere by the overlying plate; there is no indication of fossil lithospheric anisotropy in the plate spreading direction. In contrast, beneath the center of the archipelago the upper mantle is isotropic or weakly anisotropic. The isotropic region coincides approximately with a volume of anomalously low upper mantle velocities, suggesting that the presence of melt may weaken the effects of fabric on anisotropy or that melt preferred orientation generates a vertical fast polarization direction. Alternatively, the complex flow field associated with a near-ridge hotspot may result in apparent isotropy.
27 citations
01 Mar 2005
Abstract: Steven A. Hauck, II, Bruce M. Jakosky, Roger J. Phillips, and Maria T. Zuber. Dept. of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, DC 20015; Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125; Dept. of Geological Sciences, Case Western Reserve University, Cleveland, OH 44106; Laboratory for Atmospheric and Space Physics and Dept. of Geological Sciences, University of Colorado, Boulder, CO 80309; Dept. of Earth and Planetary Sciences, Washington University, St. Louis, MO 63130; Dept. of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139.
2 citations