Silica sand is widely used in the transformation industry. For instance, it is used in the making of glass, silicates, paints, glass-ceramics and ceramics. Traditionally, glass and ceramic materials have been manufactured using high-purity silica and minerals taken from ore on the surface of the earth. However, during recent decades, the manufacture of household and industrial products has incr...

We present a novel approach for numerical simulation of uid ow and sediment transport past evolutionary landforms, with emphasis on sand dunes developing in extreme winds. Time-dependent curvilinear coordinates are employed to fully couple ow aloft with the developing landform. The conservation law that de nes shape of the lower boundary depends on details of local surface stress, thereby favou...

Results from a three-year study are presented that integrate field work (in Israel), physical modeling (wind-tunnel testing at UC Davis), and numerical solutions of grain trajectories to model and explain sand transport over a climbing dune. Field grain-size analyses of surfaceand saltation-trap materials taken along various positions of the slope suggest that only smaller particles (< 230 pm i...

Introduction: THEMIS and MOC images acquired over the Chasma Boreale contain key geologic and stratigraphic information relating to aeolian deposition and the Polar Layered Deposits (PLD). Preliminary analyses of THEMIS VIS and MOC images show a clear progression of morphologic change of dark albedo dune deposits along the chasma axis. Geologic Relations: The source for the dunes appears to be ...

Irreplaceable, self-organizing landforms and the endemic and ecologically specialized biodiversity they support are threatened globally by anthropogenic disturbances. Although the outcome of disrupting landforms is somewhat understood, little information exists that documents population consequences of landform disturbance on endemic biodiversity. Conservation strategies for species dependent u...

Differences in the composition of aeolian sand at Big Dune and Lava that is mixed with basalt various minerals may affect water retention development insects are specialized for living environments. These two dunes, located Nye County, Nevada, home to endemic dune scarab beetle, Pseudocotalpa giulianii (PSGU). The differences type influence growth patterns eggs larvae this beetle species hatche...

introduction movement of sand dunes is an important natural threat in the coast of oman sea. now many rural settlements of the region are in threat, and vulnerability has caused heavy losses. the sand dunes are visible in the wide area and wind erosion occurs in a wide spatial scale. wind erosion faces high intensity in the area, because of poor vegetation, low rainfall, dry soil, strong and co...

The main objective of this study is to compare the mechanical behavior two sands (Hostun or Dune sands) mixed with crushed rubber obtained from used tires. However, it essential ensure that his geotechnical application do not result in long-term negative impacts on environment. chemical properties these are given by energy dispersive analysis X-ray fluorescence spectrometry. mineral composition...

Revegetation on moving sand dunes is a widely used approach for restoring the degraded sandy land in northeastern China. The development of sand-fixation forest might improve structures soil microbial communities and affect N cycle. In present study, diversities nitrite (nirS nirK) nitrous oxide (nosZ) reductase genes were investigated under chronosequence Caragana microphylla shrub (9- 19-year...