Surface Sediments of the Pearl River Estuary (South China Sea) - Spatial Distribution of Sedimentological/Geochemical Properties and Environmental Interpretation

The Pearl River Delta (South China) is one of the densest populated regions of the world. This study aims at the investigation and interpretation of the spatial distribution of grain size parameters and geochemical parameters obtained from surface sediment samples. These samples have been taken during cruises in 2003, 2004 and 2005. Investigations of the spatial correlations of the parameters obtained reveal an approximately north-south directed trend for the majority of the parameters. The trend was removed before applying Ordinary Kriging for interpolation. The maps obtained show non-uniform distribution patterns of the sedimentological and geochemical parameters. Here e.g. the concentrations of the As, Co, Cu, Hg and Ni decrease to the more marine influenced southeastern parts and show a higher concentration in the central part and at the western shoals of the estuary.The Pearl River Delta (South China) is one of the densest populated regions of the world. This study aims at the investigation and interpretation of the spatial distribution of grain size parameters and geochemical parameters obtained from surface sediment samples. These samples have been taken during cruises in 2003, 2004 and 2005. Investigations of the spatial correlations of the parameters obtained reveal an approximately north-south directed trend for the majority of the parameters. The trend was removed before applying Ordinary Kriging for interpolation. The maps obtained show non-uniform distribution patterns of the sedimentological and geochemical parameters. Here e.g. the concentrations of the As, Co, Cu, Hg and Ni decrease to the more marine influenced southeastern parts and show a higher concentration in the central part and at the western shoals of the estuary

Great Britain: the intertidal and underwater archaeology of Britain’s submerged landscapes

The submerged landscapes around Great Britain are extensive and would have offered productive territory for hunting, gathering, exploitation of aquatic and marine resources, and—in the final stages of postglacial sea-level rise—opportunities for agriculture. They would also have provided land connections to continental Europe and opportunities for communication by sea travel along now-submerged palaeocoastlines and river estuaries. Most of the archaeological material has been discovered in intertidal or shallow water conditions, but there are also discoveries in deeper water, with dates ranging from earliest human presence nearly one million years ago up to the establishment of modern sea level. Some later material is present where coastlines have continued to sink in more recent millennia. Intertidal sites are especially well represented because of relatively large tidal ranges and shallow offshore gradients on many coastlines. These are often associated with remains of submerged forests, which are periodically exposed at low tide and then covered up again by movements of sand. Some of the most distinctive intertidal finds are the human and animal footprints preserved in intertidal sediments in many locations, especially at Goldcliff East. The earliest, at Happisburgh, are dated between 0.78 and 1 Ma. Fully submerged sites include the Mesolithic site of Bouldnor Cliff with its worked timbers, and the Middle Stone Age artefacts from offshore aggregate Area 240 along with well-preserved ice age fauna and environmental indicators. Pioneering work using oil industry seismic records has produced detailed reconstructions of the submerged landscape, and this is being followed up by new work involving targeted acoustic survey and coring of sediments

State-Sponsored Mass Killing in African Wars—Greed or Grievance?

Mass killing, Civil war, Africa,

Holocene morphogenesis at the southern Baltic Sea: Simulation of multi-scale processes and their interactions for the Darss-Zingst peninsula

A modeling methodology based on a multi-scale hybrid morphodynamic model and representative climatic driving conditions is presented to study the long-term morphological evolution of wave-dominated coasts on a centennial-to-millennial scale. The Darss-Zingst peninsula at the southern Baltic Sea, which developed during the last 6000 years by a combined effect of eustatic sea level change, isostatic movement, meteorological drivers and nearshore sediment dynamics, is selected for a case study. A paleo-Digital Elevation Model (DEM) serving as initial condition is reconstructed by a compilation of recent digital elevation data sets, an eustatic sea-level curve, an isostatic map and dated sediment cores. Representative wind series are generated based on a statistical analysis of paleo-wind data from a simulation with the coupled atmosphere-ocean general circulation model ECHO-G over the last 7000 cal yr. These wind data were calibrated by proxies from lithostratigraphic studies of sediment cores from the central Baltic Sea, and used as climate driving conditions for the morphodynamic model. Based on the reconstructed paleo-DEM and the representative climatic driving conditions, the methodology is applied to reconstruct the Holocene morphogenesis of the Darss-Zingst peninsula since 6000 cal yr BP. Simulation results indicate that the development of the barrier system is a combination of long-term effects of climate change, isostatic crustal movement, wave dynamics and eolian transport with short-term effects of extreme wind events, i.e. storms. (c) 2013 Elsevier B.V. All rights reserved

Composite fermions in 2 {times} 10{sup 6} cm{sup 2}/Vs mobility AlGaAs/GaAs heterostructures grown by MOCVD

The authors report on the recent growth by MOCVD of 2.0 {times} 106 cm2/Vs mobility heterostructures. These mobilities, the highest reported to date, are attributed to the use of tertiarybutylarsine as the arsenic precursor. Measurements in tilted magnetic fields of the fractional quantum Hall effect (FQHE) states near filling factor 3/2 are consistent with a spin-split composite fermion (CF) model proposed earlier. The extracted values of the product of the CF g-factor and CF effective mass agree with values previously obtained for MBE samples