The Selima Sand Sheet occupies more than 120,000km2 of the hyperarid, uninhabited Darb el-Arba'in Desert centered at the border of Egypt and Sudan at latitude 22" N, and is characterized by a featureless surface of lag granules and fine sand broken only by widely separated dune fields and giant ripples of varying height and wavelength. Monitoring of the largest of these chevron-shaped ripples u...

New paleomagnetic and stable isotopic results from the northeastern margin of the greater Green River Basin (South Pass, Wyoming) provide a re®ned geochronological context for the Wasatchian/Bridgerian Land Mammal Age boundary and suggest the existence of large amplitude Milankovich-scale carbon and oxygen isotopic oscillations in this area during the early Eocene. Analysis of 55 paleomagnetic ...

Pedogenesis can be slow or fast depending on the internal chemical response to environmental forcing factors. When a shift in the external environment does not produce any pedogenic change even though one is expected, the soil is said to be in a state of pedogenic inertia. In contrast, soil properties sometimes change suddenly and irreversibly in a threshold response to external stimuli or inte...

Sediment grain-size distribution (GSD) provides rich information about sedimentary sources and can potentially do the same with regard to environmental climatic changes. However, neither traditional descriptive statistics nor curving-fitting methods fully address its complexity. We selected Greater Khingan Range in northeastern China as study area used parameterized end-member analysis (EMA) of...

480 D use diff erent strategies to survive and fl ourish with erratically available water (Hamerlynck et al., 2002; Lombardini, 2006). Th e persistence of soil water within a particular depth range and its characteristic time scales of fl uctuation (Katul et al., 2007) help determine the resulting plant community. Th e depth to which infi ltration percolates and the degree to which water is ret...

Abstract. Land use is recognized to impact soil geochemistry on the centennial millennial timescale, with implications for distribution and stability of organic carbon (SOC). Young volcanic soils in tropical areas are subject much faster pedogenesis, noticeable already or even decadal timescale. As land a factor formation, it thus conceivable that relatively recent conversion such would bear si...

Although central Iran is pivotal for palaeoclimatic correlations, palaeoenvironmental data this region very sparse and a reliable chronology pedogenic features lacking. We therefore tried to answer the question how environmental conditions and, in particular, climate developed over time by using isotopic signatures of carbonates. present carbonates association with stable carbon oxygen isotopes...