Please cite this article in press as: Graham, C. doi:10.1016/j.jhydrol.2009.12.015 Hillslope threshold response to storm rainfall is poorly understood. Basic questions regarding the type, location, and flow dynamics of lateral, subsurface flow remain unanswered, even at our most intensively studied field sites. Here we apply a forensic approach where we combined irrigation and excavation experi...

The occurrence and genesis of Ca(OH)2 and Mg(OH)2 deposits associated with hyperalkaline groundwater from partly serpentinized ultramafic rocks in Northern Oman is reported. Two types of Ca(OH)2 deposit are differentiated; crystalline portlandite formed by the evaporation of Ca 2 + 2 O H spring waters, and a form of amorphous gel, not previously known in nature. The latter is a product of prese...

Ultramafic soils are originated from ultramafic rocks such as peridotite and serpentinite highly enriched in metals (e.g., Ni, Cr, Co) depleted plant nutrients P, K, Ca). Such characteristics make these unfavorable for agriculture have raised environmental concerns on metal release to the environment. From another perspective, host a diverse flora with higher endemism than surrounding non-ultra...

Recent theoretical investigations suggest that the rate of river incision into bedrock depends nonlinearly on sediment supply, challenging the common assumption that incision rate is simply proportional to stream power. Our measurements from laboratory abrasion mills support the hypothesis that sediment promotes erosion at low supply rates by providing tools for abrasion, but inhibits erosion a...

, 369 (1997); 275 Science et al. Alexander L. Densmore, Hillslope Evolution by Bedrock Landslides www.sciencemag.org (this information is current as of September 3, 2008 ): The following resources related to this article are available online at http://www.sciencemag.org/cgi/content/full/275/5298/369 version of this article at: including high-resolution figures, can be found in the online Update...

[1] One potential consequence of global climate change and rapid changes in land use is an increased risk of flooding. Proper understanding of floodwater infiltration thus becomes a crucial component of our preparedness to meet the environmental challenges of projected climate change. In this paper, we present the results of a long-term infiltration experiment performed on fractured ash flow tu...

Alteration of ultramafic rocks plays a major role in the production of hydrocarbons and organic compounds via abiotic processes on Earth and beyond and contributes to the redistribution of C between solid and fluid reservoirs over geological cycles. Abiotic methanogenesis in ultramafic rocks is well documented at shallow conditions, whereas natural evidence at greater depths is scarce. Here we ...

Chromite is widely distributed in the east and southeast of Afghanistan, especially in Logar Province. Chromite mineralization is podiform-type and is hosted in the stratigraphically lowest ultramafic rocks of the Logar Ophiolite Complex. This ophiolite complex represents a remnant of an early Cretaceous oceanic crust that was thrusted over a late Permian to Mid-Jurassic platform-type sequence ...