Geophysical mass flows such as debris flows, dense pyroclastic and snow avalanches can self-channelize on shallow slopes. The confinement afforded by formed levees helps to maintain the flow depth, hence mobility, allowing self-channelized run out significantly farther than unconfined, spreading flows. Levee formation self-channelization are strongly associated with particle-size segregation, b...

We report on direct measurements of the basal force components for granular material flowing down a smooth incline. investigate flows large range inclination angles from $\ensuremath{\theta}=13.{4}^{\ensuremath{\circ}}$ to 83.6\ifmmode^\circ\else\textdegree\fi{} and various gate openings chute. find that effective friction coefficient ${\ensuremath{\mu}}_{B}$, obtained ratio longitudinal normal...

Abstract The Mars Science Laboratory Curiosity rover has explored over 400 m of vertical stratigraphy within Gale crater to date. These fluvio‐deltaic, lacustrine, and aeolian strata have been well‐documented by Curiosity's in situ remote science instruments, including the Mast Camera (Mastcam) pair multispectral imagers. Mastcam visible near‐infrared spectra can broadly distinguish between iro...

Booming” sand dunes have a remarkable capacity to produce sounds that are comparable with those from a stringed instrument. This phenomenon, in which sound is generated after an avalanching of sand along the slip face of a dune, has been known for centuries and occurs in at least 40 sites around the world. A spectral analysis of the sound shows a dominant frequency between 70 and 110 Hz, as wel...

Rivers shape continental surfaces; they erode continental reliefs, transport erosion products and finally deposit them in plains. As a consequence, understanding physics of sediment transport is of fundamental importance in earth sciences. However, sediment transport occurs at the dynamical interface between fluid and granular mechanics, which makes its full understanding challenging. Over the ...

– We investigate the effects of lateral walls on the angle of movement and on the angle of repose of a granular pile. Our experimental results for beads immersed in water are similar to previous results obtained in air and to recent numerical simulations. All of these results, showing an increase of pile angles with a decreasing gap width, are explained by a model based on the redirection of st...

© The Ecological Society of America www.frontiersinecology.org F many scientists, the only dust they think about is the thin film of material that accumulates on their computer monitor on a regular basis. However, dust has enormous relevance to a wide range of ecological processes and environmental management challenges. Dust is fine particulate material that is removed from the land surface by...