Publications by authors named "Ola A Eggen"

Today the vast majority of commercial laboratories are accredited. Quality control (QC) results are documented and, upon request, available to the customer. That has led many customers of analytical services to neglect the need for their own, laboratory independent, external QC for large geochemical mapping or monitoring projects.

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Data sets for concentrations of up to 22 elements including Pb, Cd, Ag, As, and Hg and several rare earth elements (REEs) in moss and surface soil from all over mainland Norway are analyzed by positive matrix factorization (PMF) and principal component analysis (PCA) with centered log-ratio transformation. Moss and soil samples collected in 2010 and 2005, respectively, show both a distinct long-range atmospheric transport PMF factor including a dominant Pb loading along with smaller loadings of Mo, Cd, Sb, and As, and a geogenic factor dominated by Ce, La, and Y. Other PMF factors for moss and soil are mainly anthropogenic except for two soil factors, a Cr, Co, Ce dominated factor, and an Eu factor.

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The 7000 years transition from a pristine environment towards a modern city has brought a number of chemical changes and effects to urban lake sediments in Bergen. Metals, such as Pb, Hg, Zn, Cu and Fe, display a large anthropogenic influence and reflect historical point sources that existed within the drainage area from approximately AD 1790 until today. The concentration peaks alternate with intervals of lower concentration due to phases of coarser grained sediment input but also periods of potentially reduced metal influx.

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This study aims to determine the temporal character and concentration variability of polycyclic aromatic hydrocarbon (PAH) during the last 5,400 years in urban lake sediments through a combination of dating and chemo-stratigraphical correlation. We investigate the chemical history of the city of Bergen and determine the effect of specific point sources, as well as diffuse sources, and also help assess the risk of remediation plans. By using several organic compounds, metals and cyanide, we demonstrate the more accurate timing of sedimentation.

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