Publications
Filter Total Items: 922
Regional-scale stratigraphy of surface units in Tyrrhena and Iapygia Terrae, Mars: Insights into highland crustal evolution and alteration history
The compositional, thermophysical and geologic characteristics of surface units in Iapygia and Tyrrhena Terra (60°E–100°E, 0°–30°S) provide new insights into the compositional stratigraphy of the region. Intercrater plains are dominated by two surface units. The older unit (unit 1) is deficient in olivine and more degraded and likely consists of a mixture of impact, volcanic and sedimentary materi
Authors
A. Deanne Rogers, Robin L. Fergason
The Mairan domes: silicic volcanic constructs on the Moon
The Mairan domes are four features located in northern Oceanus Procellarum at ∼312.3E, 41.4N on the Moon. High resolution visible imagery, visible-to-mid-IR spectra, and Lunar Prospector Th abundance data all indicate that these four domes have a composition that is consistent with derivation from a Si-rich, highly evolved magma.
Authors
Timothy D. Glotch, Justin Hagerty, Paul G. Lucey, B. Ray Hawke, Thomas A. Giguere, Jessica A. Arnold, Jean-Pierre Williams, Bradley L. Jolliff, David A. Paige
Estimating eruption temperature from thermal emission spectra of lava fountain activity in the Erta'Ale (Ethiopia) volcano lava lake: Implications for observing Io's volcanoes
[1] We have analysed high‐spatial‐resolution and high‐temporal‐resolution temperature measurements of the active lava lake at Erta'Ale volcano, Ethiopia, to derive requirements for measuring eruption temperatures at Io's volcanoes. Lava lakes are particularly attractive targets because they are persistent in activity and large, often with ongoing lava fountain activity that exposes lava at near‐er
Authors
A.G. Davies, Laszlo P. Keszthelyi, A. S. McEwen
Seasonal erosion and restoration of Mars' northern polar dunes
Despite radically different environmental conditions, terrestrial and martian dunes bear a strong resemblance, indicating that the basic processes of saltation and grainfall (sand avalanching down the dune slipface) operate on both worlds. Here, we show that martian dunes are subject to an additional modification process not found on Earth: springtime sublimation of Mars' CO 2 seasonal polar caps.
Authors
C.J. Hansen, M. Bourke, Nathan T. Bridges, Shane Byrne, C. Colon, S. Diniega, Colin M. Dundas, Kenneth E. Herkenhoff, A. McEwen, M. Mellon, Ganna Portyankina, N. Thomas
The indication of Martian gully formation processes by slope-area analysis
The formation process of recent gullies on Mars is currently under debate. This study aims to discriminate between the proposed formation processes - pure water flow, debris flow and dry mass wasting - through the application of geomorphological indices commonly used in terrestrial geomorphology. High-resolution digital elevation models (DEMs) of Earth and Mars were used to evaluate the drainage c
Authors
Susan J. Conway, Matthew R. Balme, John B. Murray, Martin C. Towner, Chris Okubo, Peter M. Grindrod
Volcanism on Io: New insights from global geologic mapping
We produced the first complete, 1:15 M-scale global geologic map of Jupiter’s moon Io, based on a set of monochrome and color Galileo–Voyager image mosaics produced at a spatial resolution of 1 km/pixel. The surface of Io was mapped into 19 units based on albedo, color and surface morphology, and is subdivided as follows: plains (65.8% of surface), lava flow fields (28.5%), mountains (3.2%), and p
Authors
David A. Williams, Laszlo P. Keszthelyi, David A. Crown, Jessica A. Yff, Windy L. Jaeger, Paul M. Schenk, Paul E. Geissler, Tammy L. Becker
Active aeolian processes on Mars: A regional study in Arabia and Meridiani Terrae
We present evidence of widespread aeolian activity in the Arabia Terra/Meridiani region (Mars), where different kinds of aeolian modifications have been detected and classified. Passing from the regional to the local scale, we describe one particular dune field in Meridiani Planum, where two ripple populations are distinguished by means of different migration rates. Moreover, a consistent change i
Authors
S. Silvestro, D.A. Vaz, L.K. Fenton, Paul E. Geissler
Thorium abundances of basalt ponds in South Pole-Aitken basin: Insights into the composition and evolution of the far side lunar mantle
Imbrian-aged basalt ponds, located on the floor of South Pole-Aitken (SPA) basin, are used to provide constraints on the composition and evolution of the far side lunar mantle. We use forward modeling of the Lunar Prospector Gamma Ray Spectrometer thorium data, to suggest that at least five different and distinct portions of the far side lunar mantle contain little or no thorium as of the Imbrian
Authors
Justin Hagerty, D. J. Lawrence, B. R. Hawke
Channel morphometry, sediment transport, and implications for tectonic activity and surficial ages of Titan basins
Fluvial features on Titan and drainage basins on Earth are remarkably similar despite differences in gravity and surface composition. We determined network bifurcation (Rb) ratios for five Titan and three terrestrial analog basins. Tectonically-modified Earth basins have Rb values greater than the expected range (3.0–5.0) for dendritic networks; comparisons with Rb values determined for Titan basi
Authors
R. Cartwright, J.A. Clayton, Randolph L. Kirk
Opportunity Mars Rover mission: Overview and selected results from Purgatory ripple to traverses to Endeavour crater
Opportunity has been traversing the Meridiani plains since 25 January 2004 (sol 1), acquiring numerous observations of the atmosphere, soils, and rocks. This paper provides an overview of key discoveries between sols 511 and 2300, complementing earlier papers covering results from the initial phases of the mission. Key new results include (1) atmospheric argon measurements that demonstrate the imp
Authors
R. E. Arvidson, James W. Ashley, J.F. Bell, M. Chojnacki, J. Cohen, T.E. Economou, W. H. Farrand, Robin L. Fergason, I. Fleischer, Paul E. Geissler, Ralf Gellert, M.P. Golombek, J.P. Grotzinger, E.A. Guinness, R.M. Haberle, Kenneth E. Herkenhoff, J.A. Herman, K.D. Iagnemma, B.L. Jolliff, J. R. Johnson, G. Klingelhofer, A.H. Knoll, A.T. Knudson, R. Li, S. M. McLennan, D. W. Mittlefehldt, R.V. Morris, T. J. Parker, M.S. Rice, C. Schroder, Laurence A. Soderblom, S. W. Squyres, R.J. Sullivan, M.J. Wolff
Columbus crater and other possible groundwater-fed paleolakes of Terra Sirenum, Mars
Columbus crater in the Terra Sirenum region of the Martian southern highlands contains light‐toned layered deposits with interbedded sulfate and phyllosilicate minerals, a rare occurrence on Mars. Here we investigate in detail the morphology, thermophysical properties, mineralogy, and stratigraphy of these deposits; explore their regional context; and interpret the crater's aqueous history. Hydrat
Authors
J.J. Wray, R.E. Milliken, Colin M. Dundas, Gregg A. Swayze, J. C. Andrews-Hanna, A.M. Baldridge, M. Chojnacki, J.L. Bishop, B.L. Ehlmann, S.L. Murchie, Roger N. Clark, F.P. Seelos, L.L. Tornabene, S. W. Squyres
Hyperspectral analysis of rocky surfaces on the Earth and other planetary systems: Chapter 27
This book is focused on studies of vegetation on Earth using hyperspectral remote sensing methods. However, it is appropriate to extend the application of these methods out to other rocky bodies in our Solar System for a variety of reasons. First, minerals, soils, and rocks form the substrate on which vegetation grows on Earth. Compositional analyses of these components with hyperspectral data pro
Authors
R. Greg Vaughan, Timothy N. Titus, Jeffery R Johnson, Justin Hagerty, Lisa R. Gaddis, Laurence A. Soderblom, Paul E. Geissler