Southern elephant seal trajectories, fronts and eddies in the Brazil/Malvinas Confluence

This study describes the association between transient, mesoscale hydrographic features along the axis of the Brazil–Malvinas Confluence, in the SW Atlantic, and the foraging behavior of 2–3-year-old (focal) juvenile southern elephant seals, Mirounga leonina, from Península Valdés, Argentina. Departing from the dominant pattern of foraging on predictable bathymetric fronts on the Patagonian shelf and slope, three females out of 12 satellite-tracked juveniles remained at the edge of young warm-core eddies and near the outer core of cold-core eddies, coinciding with the most productive areas of these temperature fronts. Seal trajectories along high-temperature gradients were always consistent with the speed and direction of surface currents inferred from the temperature distribution and confirmed by surface drifters. Movements of foraging seals were compared with those of surface drifters, coinciding in time and space and yielding independent and consistent data on regional water circulation parameters. The diving pattern recorded for one focal seal yielded shallower dives and a loose diel pattern in the eddy, and a marked diurnal cycle compatible with foraging on vertically migrating prey in the cold waters of the Malvinas Current. Pre-reproductive females that use the mesoscale fronts of the Argentine Basin as an alternative foraging area would benefit from lower competition with more experienced seals and with other top predators that reproduce along the coast of Patagonia.     

Geochemical types of Volkhovites and possible diamond resource potential of areas occupied by Holocene fluidisites

Volkhovites—tektite-like glasses—have been detected in the Holocene glacial drift along the right bank of the Volkhov River. A cryptomagmatic model of their formation and pre-Holocene age of volkhovite melts, cinder, and frothed glasses has been suggested (Skublov et al., 2007). Four geochemical types of volkhovites are distinguished: (1) manganous (Mn, Fe, Cr, V, Si, Nb, Pb, H), (2) magnesian (Mg, Al, Ti, F, B), (3) potassic (K, Rb, Cs), and (4) calcic (Ca, REEs, Ba, U, Th, Ta, Hf, Y, Sc, Cl). In light of the geochemical data, volkhovites are regarded as natural silicate glasses of kimberlite-carbonatite composition. Their types are called kimberlitic (Mn type), kimberlitic-carbonatitic (Mg type), lamproitic-carbonatitic (K type), and carbonatitic (Ca type). Volkhovites are suggested to be indicators of undiscovered diamond mineralization of kimberlite or carbonatite (Chagatai) types.     

The current ethnic panorama in Bulgaria

Although a constant trickle of outmigrants and several larger waves (mostly to Turkey) are characteristic for the modern history of Bulgaria, its ethnic composition was relatively stable. The ethnic Bulgarians are a clear majority, the largest minority groups being in descending order the Turks, Roma (Gypsies), the Muslim Bulgarians and several much smaller groups. The geographical patterns of distribution have been analysed. Over time, the policies of the Bulgarian state towards the minority groups have been varying between benevolence and restriction measures. The ethnocultural communities have worked out moduses of co-existence preventing the escalation of conflicts at the local level.     

Stock-Specific Movement and Distribution of Juvenile Chinook Salmon, <Emphasis Type="Italic">Oncorhynchus tshawytscha</Emphasis>, in Sandy Beach Surf Zones of Oregon and Washington,USA

Sandy beach surf zones serve as alternative nursery habitats for juvenile Chinook salmon (0 age) during their early marine residency, a period considered critical due to high and variable mortality rates. Despite the importance of early marine residence, the extent of juvenile salmon surf zone use and movement along sandy beaches is not well understood. Juvenile Chinook salmon distribution and movement were studied in shallow surf zone habitats by sampling from 2006 to 2010 with a beach seine 11 beaches adjacent and distant to four estuary mouths in Oregon and Washington, USA. The estuary of origin of each juvenile was determined using genetic stock identification methods and coded wire tags. Surf zones sampled were within littoral cells, which are stretches of the coastline bordered by rocky headlands, and included estuaries with and without Chinook salmon populations. Juvenile salmonids were only collected at littoral cells with Chinook-inhabited watersheds. Most juveniles (95 %) were present at sandy beaches adjacent (<500 m from estuary mouth) to their estuary of origin. Few Chinook salmon (5 %) were collected at littoral cells that contained non-natal estuaries. These results indicate that juvenile Chinook salmon inhabiting surf zones mostly use beaches adjacent to their estuaries of origin, but some juveniles may reside in beaches distant from their point of ocean entry.     

Dynamic of the freshwater–saltwater interface in a karstic aquifer under extraordinary recharge action: the Merida Yucatan case study

A hydraulic analysis of the interface between freshwater–saltwater behavior was done in the Merida Yucatan zone, two machines that constantly register the groundwater levels were installed, and three electric conductivity logs were taken from wells. When comparing the measured results with the ones obtained using theoretical equations developed to calculate the freshwater–saltwater interface position, it was proved that in some cases these equations can be applied, and in others not. Two effects that rule the behavior of karst aquifers in extraordinary conditions were found.     

Hadean-archean detrital zircons from Jatulian quartzites and conglomerates of the Karelian craton

Using local procedures, the new results on the isotope ages and composition of mineral inclusions were obtained for detrital zircons from Paleoproterozoic Jatulian terrigenous quartzites and polymictic conglomerates in Central and Western Karelia. For Eastern Laurasia, signs of the existence of Hadean and ancient Eoarchean matter were found for the first time (zircon grains of 3871 ± 38.6 and 3837 ± 42.1 Ma concordant ages). The multimodal distribution of ages within 3.45−2.61 Ga was revealed. The discovery of the oldest zircon grains provides the conditions for valid global correlations of geological events that determined the deposition and formation of the continental crust of the North Atlantic supercraton.     

GGR Biennial Critical Review: Analytical Developments Since 2014

This GGR biennial critical review covers developments and innovations in key analytical methods published since January 2014, relevant to the chemical, isotopic and crystallographic characterisation of geological and environmental materials. In nine selected analytical fields, publications considered to be of wide significance are summarised, background information is provided and their importance evaluated. In addition to instrumental technologies, this review also presents a summary of new developments in the preparation and characterisation of rock, microanalytical and isotopic reference materials, including a précis of recent changes and revisions to ISO guidelines for reference material characterisation and reporting. Selected reports are provided of isotope ratio determinations by both solution nebulisation MC‐ICP‐MS and laser ablation‐ICP‐MS, as well as of radioactive isotope geochronology by LA‐ICP‐MS. Most of the analytical techniques elaborated continue to provide new applications for geochemical analysis; however, it is noted that instrumental neutron activation analysis has become less popular in recent years, mostly due to the reduced availability of nuclear reactors to act as a neutron source. Many of the newer applications reported here provide analysis at increasingly finer resolution. Examples include atom probe tomography, a very sensitive method providing atomic scale information, nanoscale SIMS, for isotopic imaging of geological and biological samples, and micro‐XRF, which has a spatial resolution many orders of magnitude smaller than conventional XRF.     

Evaluation of equivalence between different methods for enumeration of fecal indicator bacteria before and after adoption of the new Bathing Water Directive and risk assessment of pollution

The quality of bathing water is of considerable public importance due to the possibility of fecal contamination. In 2009, Croatia implemented the new European Bathing Water Directive (BWD, 2006/7/EC) establishing stricter microbiological standards for new parameters with new reference methods. This study aims to evaluate the equivalence of different methods according to the old and revised BWD and to provide the possibility of data comparison. Furthermore, the directive requires the establishment of the bathing water profile (BWP) for pollution risk assessment. The estimation of consistency of pollution risk assessment with obtained microbiological results was also performed.