Published in Icarus
Zumba is a∼ 2.9 km diameter rayed crater on Mars located on extensive lava plains in Daedalia Planum to the southwest of Arsia Mons. It is a well-preserved young crater with large ejecta rays that extend for hundreds of kilometers from the impact site. The rays are thermally distinct from the background lava flows in THEMIS daytime and nighttime th...
Published in Planetary and Space Science
The “ponds” on asteroid (433) Eros are fine-grained deposits approximating flat (quasi-equipotential) surfaces with respect to local topographic depressions (eg, craters) in spacecraft images. These ponds are discussed in the context of laboratory simulation experiments, crater-related ponded and pitted deposits observed on Mars and Vesta, terrestr...
Published in Geological Society of America Special Papers
The~ 31.7-km-diameter Betio crater (23.15 S, 281.38 E), located within the Hesperian-aged Ridged Plains material in Thaumasia Planum, Mars, contains a well- preserved asymmetrical central floor pit (~ 10.8 km NW-SE and~ 8.8 km NE-SW in diameter) covering an area of~ 67 km 2 that exposes discrete megablocks of layered bedrock and preserves a variety...
Published in Icarus
Hypotheses ranging from fluvial processes and debris flows to CO 2 frost-lubricated or entirely dry flows have been proposed for the formation of martian gullies. In order to constrain these potential formation mechanisms, we mapped the global distribution of gullies on Mars using> 54,000 images from the Mars Reconnaissance Orbiter (MRO) Context Ca...
Published in Icarus
Ritchey crater is a∼ 79 km diameter complex crater near the boundary between Hesperian ridged plains and Noachian highland terrain on Mars (28.8 S, 309.0 E) that formed after the Noachian. High Resolution Imaging Science Experiment (HiRISE) images of the central peak reveal fractured massive bedrock and megabreccia with large clasts. Compact Reconn...
Published in 2014 GSA Annual Meeting in Vancouver, British Columbia
Many mid-latitude craters on Mars exhibit morphologically distinct post-impact “fill” material on their floors. This material is inferred to be (or have been) ice-rich based on morphological characteristics such as evidence for flow and removal, and their morphologic similarity to ice- rich lobate debris aprons and lineated valley fill. These latte...
Published in 2014 GSA Annual Meeting in Vancouver, British Columbia
The characteristics of pristine impact crater ejecta are not well understood, but stand as an important baseline for better understanding impact processes. It is generally accepted that on airless bodies, most ejecta blanket material is emplaced radially by ballistic transport. This process, however, does not account for all ejecta facies, such as ...
Published in Journal of Geophysical Research: Planets
Published in Journal of Geophysical Research: Planets
Published in Journal of Geophysical Research: Planets
Published in Journal of Geophysical Research: Planets
Published in Journal of Geophysical Research Space Physics
Published in Geophysical Research Letters
Published in Geophysical Research Letters
[1] The Terra Sirenum region of Mars, located in the Noachian southern highlands, is mineralogically diverse, providing unique insight into ancient aqueous processes. Analyses of remote sensing data over the region indicate the presence of both Fe-or Mg-rich phyllosilicates and a spectrally unique deposit interpreted to be rich in chloride salts. T...
Published in Proceedings of the National Academy of Sciences
Hundreds of impact craters on Mars contain diverse phyllosilicates, interpreted as excavation products of preexisting subsurface deposits following impact and crater formation. This has been used to argue that the conditions conducive to phyllosilicate synthesis, which require the presence of abundant and long-lasting liquid water, were only met ea...
Published in Journal of Geophysical Research Space Physics
Published in Journal of Geophysical Research Space Physics
Published in Geology
