We investigated sediments from 23 lakes situated in northeastern Poland and analyzed them for major constituents and selected heavy metals. Short sediment cores were collected from the deepest parts of the lakes, and subsequently, a surface layer (0-2 cm) and reference layer (50-52 cm) were sampled from each. In the collected samples, the content of the major constituents (organic matter, carbo...

A reliable geochemical paleo-indicator for phosphorus remains elusive, despite the importance of understanding historical changes in the nutrient status of aquatic ecosystems. We assessed the potential of phytate (salts of mvo-inositol hexakisphosphate) as a novel phosphorus-specific paleoindicator by measuring its concentrations in dated sediments from an embayment in Helsinki, Finland, with a...

Correlation analyses were conducted on nickel (Ni), vanadium (V) and zinc (Zn) oral bioaccessible fractions (BAFs) and selected geochemistry parameters to identify specific controls exerted over trace element bioaccessibility. BAFs were determined by previous research using the unified BARGE method. Total trace element concentrations and soil geochemical parameters were analysed as part of the ...

Using in-field bioreactors, we investigated the influence of exogenous microorganisms in groundwater planktonic and biofilm microbial communities as part of the Integrated Field Research Challenge (IFRC). After an acclimation period with source groundwater, bioreactors received either filtered (0.22 μM filter) or unfiltered well groundwater in triplicate and communities were tracked routinely f...

The Dublin SURGE (Soil Urban Geochemistry) Project is Dublin's first baseline survey of heavy metals and persistent organic pollutants in topsoils and is part of a Europe-wide initiative to map urban geochemical baselines in ten cities. 1,058 samples were collected as part of a stratified random sampling programme in the greater Dublin area to give an overview of baseline conditions in the city...

r a 200 .027 sent add gmail.c Summary Inverse geochemical modeling (PHREEQC) was used to identify the evolution of groundwater with emphasis on arsenic (As) release under reducing conditions in the shallow (25–30 m) Mississippi River Valley Alluvial aquifer, Arkansas, USA. The modeling was based on flow paths defined by high-precision (±2 cm) water level contour map; X-ray diffraction (XRD), sc...

In developing the Field Investigation Report for the Waste Management Area S-SX at the Hanford Site, Cs was the only gamma emitting radionuclide of concern (Knepp 2002). However, in WMA B-BX-BY, the spectral gamma logging data identify seven gamma emitting radionuclides, Cs, Sb, Eu, Eu, Co, U, and U (DOE-GJPO 1998). The geochemical behaviors of several of these radionuclides, Sb and the two eur...

When it comes to well loss and efficiency, the occurrence of wellbore skin layers is one of the strongest influencing factors. Besides difficulties to remove the skin layer that is necessary during the drilling process, it is also not easily possible to determine if a skin layer is present in a well and whether or not it imposes a certain degree of well loss. With this work, three types of skin...

Ancient black shales have considerable potential for generation of long, high-resolution paleoclimate proxy records, given the availability of a geochemical proxy that can be easily measured. Owing to substantial differences in density between the siliciclastic matrix of black shales (2.6-2.7 g cm-) and the major non-clastic components, i.e., organic carbon, Fe-sulfide, and phosphate (ca. 1.0-1...

-This paper presents the design and development of a Geochemical Expert System prototype (GES) for analyzing solution-mineral interactions in nature. The emphasis is placed on expert system design and knowledge representation. One of the most challenging and research-intensive steps was the identification of the key geochemical characteristics that would enable the expert system to identify sal...