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Airborne particulate matter (PM) in urban areas is derived from a combination of natural and anthropogenic sources. To identify PM sources and their effects on air quality, we collected PM using active filter samplers over a two-year period in the urban Wasatch Front, northern Utah, an area affected by multiple pollution sources. Filters from active samplers and other PM samples were analyzed for major and trace element concentrations and 87Sr/86Sr ratios. We identified wind-blown mineral dust from dry lake beds, winter inversions, and fireworks as primary PM sources affecting air quality in the Wasatch Front. Dust contributes Al, Be, Ca, Co, Cs, Fe, Li, Mg, Mn, Rb, Th, U, Y, and REEs which are typical components of carbonate and silicate minerals. Winter inversions entrap As, Cd, Mo, Pb, Sb, Tl, and Zn from brake dust, combustion engine exhaust, and refining processes. Concentrations of common components of fireworks Ba, Cu, K, and Sr greatly increase (>4 times) during holidays. Strontium released from fireworks has a distinct 87Sr/86Sr ratio that dominates the isotopic composition of PM during holidays. Fireworks have 87Sr/86Sr ratios of <0.7080 compared with 0.7100 for Sevier Dry Lake and 0.7150 for Great Salt Lake lakebed. Sources of particulate matter vary seasonally. Dust events dominate the air quality signature during spring and summer while winter inversions occur from November through February. Transport of PM to mountain snowpack negatively affect water quality. This is the first study to describe variations in multiple PM sources and their potential health effects in Utah, USA

Whole-rock and mineral compositions of three eruptive deposits from the Twin Falls caldera, associated with the Yellowstone hotspot, provide a window into melt generation and evolution for hot, dry, A-type rhyolites. Three rhyolitic units were sampled via the Kimberly drill-core as a part of project HOTSPOT, a study focused on mantle plume and continental lithosphere interaction. Previous work has been done to collect high resolution U-Pb zircon ages, and Hf- and O-isotopic compositions. This study examined the geochemistry of apatite and zircon along with host rock compositions in the context of this previous work. The Kimberly core sampled the Shoshone Rhyolite (6.06 Ma, 120 m thick), Kimberly Member (7.70 Ma, 169 m thick), and Castleford Crossing Member (7.96 Ma, >1400 m thick). Apatite compositions more closely reflect the composition of their whole rock hosts than zircons. SiO2 content is higher in apatite of the Kimberly Member at (1.1 ± 0.75 wt.%), vs (0.72 ± 0.47 wt.%) for the Castleford Crossing and (0.84 ± 0.27 wt.%) for the Shoshone Rhyolite. REEs compensate for Si substitution in these apatites, with the Kimberly Member most enriched. Volatile contents in the apatites are typical of metaluminous A-type rhyolites, with very low Cl and high F concentrations. Average Ti-in-zircon crystallization temperatures were highest in the Castleford Crossing Member (847 ± 68°C), followed by the Shoshone Rhyolite (806 ± 78°C), and then the Kimberly Member (804 ± 70°C). Oxygen fugacity calculated from zircons has average ΔQFM values for the Shoshone (0.8), Kimberly (-0.2), and Castleford Crossing (0.2). Hf concentrations and Eu anomalies are comparable in zircons from all three units. REE patterns in zircons are also similar and concentrations of REEs in the Shoshone and Kimberly units are similar even though the whole rock compositions of all three units are distinct. Less than 15% of zircons in the Kimberly and Castleford Crossing rhyolites have CL-dark cores enriched in several REEs, U, and Th. These CL-dark cored zircons are likely xenocrysts entrained from chemically evolved granite and then overgrown with less enriched rims prior to eruption. There are several apatite grains with Si-LREE enriched rims in the Kimberly Member, which serves as further evidence of assimilation of silicic igneous rock by the Kimberly Member before eruption. Principal component analysis of the geochemical data distinguishes between the units using both whole-rock and apatite compositions. However, zircon compositions are not statistically distinguishable using PCA. A global comparison of Ti, U, Th, Yb, and Nb concentrations in zircons show that the zircons in the Central Snake River Plain are similar to zircons in Hawaiian basalts, while younger zircons from Yellowstone formed in cooler more differentiated magma. We propose that the zircon and apatite chemical patterns and trends confirm the A-type origin of Snake River Plain rhyolites and make it unlikely that they represent partial melts of felsic continental crust but are instead derived in large part from partial melts of young mafic crust--the midcrustal sill.

Sites contaminated with polycyclic aromatic hydrocarbons can be simultaneously contaminated with trace elements. Co-contaminated soil is considered a complex problem since inorganic and organic contaminants behave differently and thereby often require different remediation strategies. Despite the fact that co-contaminated soils are a common problem, existing research on remediation of contaminated soil mostly focuses on either organic or inorganic contaminants. In the present study, the possibilities of electrokinetic remediation as an alternative to commonly used remediation technologies was investigated. An experiment was setup to evaluate the effects of electrokinetic remediation on both polycyclic aromatic hydrocarbons and trace elements, such as arsenic, cadmium, chromium, copper, lead and zinc, simultaneously. The experiment was performed in 12 litre large plexiglass cells. Two cells with electrokinetic treatment, equipped with iron electrodes, to amend the soil with iron via intentional corrosion of the electrodes, and one control. The cells were filled with contaminated soil and deionized water was pumped through the cells to simulate a groundwater flow. The experiment ran for two months, during which pore water was sampled weekly and simulated groundwater monthly, to monitor changes in contaminant concentrations. Soil samples were taken at the start and at the end of the experiment. Results showed that the concentration of polycyclic aromatic hydrocarbons in the simulated groundwater decreased from 0.39 ± 0.15 μg L-1 to 0.12 ± 0.064 μg L-1 during the experiment. However, at the point of writing, samples of soil at the end of the experiment has not yet been analysed for concentration of polycyclic aromatic hydrocarbons, something that needs to be done to validate previously described results. In terms of the trace elements, the applied method did not increase their mobility, nor did it decrease it. Moreover, the trace elements behaved similarly in the control cell as in the treatment cells. This was observed for all the tested trace elements, indicating that electrokinetic remediation in this particulate case may be a suitable remediation technology for organic, but not that successful for inorganic contaminants. In regard to this, further research is required to establish whether electrokinetic remediation is a promising remediation technology for co- contaminated soil and how it can be optimized to ensure remediation success for both organic and inorganic contaminants.

The study gives a broad background to understand the high demand of lithium batteries in the coming years, especially in Europe. The goal of the study is to use La-ICP-MS to analyse spodumene samples from different lithium deposits in Europe to get a better knowledge of the contents of trace elements in spodumene. Due to unforeseen circumstances linked to the pandemic of COVID-19. the study had to develop an own method to calculate and convert the data acquired with the La-ICP-MS into more quantitative data.  The method developed requires more research and understanding before saying that it can be used for future research, especially for the calculation of major element Li, Al and Si as it showed a value difference to 20% of the “real value”. Source of contamination in the analysed samples (eucryptite) is also being discussed and its implication on the result. Results acquired using this method showed that some trace elements are indeed occurring in spodumene substituting the main elements and are found in all the different geological domains. These elements (Ga, Mn, Se, Fe, V, T) will then also occur in a concentrate of spodumene.

The environmental processes and conditions controlling productivity and organic matter (OM) accumulation/preservation as well as bottom–water redox conditions in the lower black shale (LBS) and upper black shale (UBS) members of the Devonian-Mississippian (D–M) Bakken Formation were evaluated utilizing trace metal (TM) concentrations, degree of pyritization (DOPT), enrichment factors (EF) of TMs, bi–metal ratios (V/Cr, V/(V+Ni), Ni/Co, U/Th), total sulfur (ST) vs. iron (Fe), total organic carbon (TOC), carbon–sulfur–iron relationships (C–S–Fe), as well as Mo–TOC and Mo EF–U EF relationships. High-resolution (1- to 3-cm scale) chemostratigraphic records were generated for twelve drill cores, four of which closely flank the N–S-trending axis of the Nesson Anticline, proximal to the center of the Williston Basin in northwest North Dakota, USA. Furthermore, five of the twelve drill cores were selected (sample selection was based on down–core spacing and TM concentrations) for petrographic and Rock-Eval analysis to assess variations in kerogen type, quantity, quality, and thermal maturity (based on solid bitumen reflectance (%SBRo), vitrinite reflectance equivalence (%VRE), Rock–Eval Tmax–derived vitrinite reflectance (%Ro)) from immature to condensate, wet gas hydrocarbon generation windows. Degree of pyritization (DOPT) values (0.25 to 1.0) indicate that bottom waters were frequently dysoxic (> 60%) with intermittent aerobic and anoxic/euxinic conditions which is in agreement with C–S–Fe and total ST vs. Fe assessments of paleoredox conditions and sedimentological evidence. Furthermore, using published Mo–TOC relationships from modern anoxic-euxinic basins, it is estimated that renewal time of the sub-chemoclinal water mass during accumulation of the LBS and UBS approximated 10 and 30 yrs., respectively. Agreement is also seen between Mo/TOC and Mo EF/U EF where both suggest the Bakken shales were deposited under relatively unrestricted water mass conditions resulting in consistent renewal of TMs into the basin. However, bi–metal ratios suggest > 80% of samples were deposited under suboxic to anoxic/euxinic conditions. Trace metal concentrations for the Bakken Fm. show considerable range for Co (0–10324 ppm), Mo (0–2018 ppm), Ni (0–1574 ppm), U (0–1604 ppm), and V (0–3194 ppm), and bi–metal ratios for the Bakken Fm. are up to 5x greater than those reported for other D–M black shale formations. The Bakken black shales represent a unique sedimentary system where the EF of various TMs such as Cu (6.2–7.7), Mo (219.7–237.8), Ni (9.4–10.2), U (20.6–29.3), V (9.9–14.2), and Zn (10.4–12.2) as well as total organic carbon contents (LBS = 10.80 and UBS = 11.80 avg. wt.%) are considerably higher than other Devonian–Mississippian black shales. In this study, raw distributions of elemental concentrations combined with bivariate and principal component analysis (PCA) were used to elucidate the processes that could have contributed to the high EF of TMs in the Bakken shales. Total organic carbon shares heavier PCA component loadings (>0.445) and stronger correlation coefficients (r) with Cu, Mo, Ni, U, V, and Zn rather than with pyrite-associated (As, Co, Fe, and S) elements, suggesting that TOC played a primary role in the scavenging and accumulation of TMs in the sediments. Reducing conditions within bottom waters or sediment pore waters may have accelerated the accumulation of redox-sensitive Cu, Mo, Ni, V, and Zn introduced into the sediments via primarily an organic matter (OM) detritus host and most likely played a secondary role in the enrichment of TMs. The high EF of TMs observed in the Bakken shales may be the result of the frequent resupply of TMs into basin waters, enhanced primary productivity that is necessary in scavenging TMs from the water column, the presence of H2S within sediment pore or bottom waters, or possibly secondary processes associated with basin-wide fluid and hydrocarbon migration. Factors controlling TM accumulation during time of deposition (e.g., TM availability, bottom-water redox conditions, adsorption onto organic matter) and during diagenesis and catagenesis (e.g., alteration and break down of organic matter, movement of fluid hydrocarbons or other basinal fluids) likely contribute to the lack of agreement between redox proxies, and subsequently, the lack of applicability of bi–metal ratios (i.e., V/Cr, V/(V+Ni), Ni/Co, U/Th) in assessing bottom–water conditions for the Bakken shales. Solid bitumen (SB), a secondary organic matter formed as a residue after hydrocarbon generation (through either sufficient thermal maturation or microbial degradation) and expulsion, is primarily dispersed within the mineral matrix and increases in quantity with increasing thermal maturity. Rock-Eval II and HAWK analyzers were used to measure and estimate the hydrogen index (HI; avg. 201 mg HC/g TOC), oxygen index (OI; avg. 7mg CO2/g TOC), S1 (free hydrocarbons; avg. 8.0 mg HC/g rock), S2 (hydrocarbons generated after cracking kerogen; avg. 24.3 mg HC/g rock), and %Ro (0.60–1.03%; estimated from Tmax). The HI and OI values are calculated from TOC as well as S2 and S3 (oxygen bonded to hydrocarbons). Plots of HI vs. Tmax (ºC) and HI vs. OI as well as S2 vs. S3 ratio were utilized to determine the type of kerogen, primary OM that is insoluble in organic solvents. However, these relationships are not in agreement with kerogen typing based on petrographic observations, where samples from more thermally mature cores plot as Type III (vitrinite) kerogen instead of observed Type I/II (marine algae) kerogen. This is largely due to the abundant presence of SB in the more thermally mature section of the Bakken (Rock-Eval Ro = 0.83–1.03%) as SB is known to have a lower HI content than Type II kerogen. Petrographic evidence shows greater abundance of alginite and amorphous organic matter (AOM or bituminite) in the thermally less mature (Rock-Eval Ro = 0.60–0.83%) section of the Bakken compared to the greater abundance of dispersed SB in the more thermally mature section where AOM is absent. Early research on the Bakken Fm. reported lower than expected vitrinite reflectance values attributed to vitrinite “suppression". The overall lack of vitrinite and abundance of solid bitumen in these shales suggests that these early attempts likely reported solid bitumen reflectance rather than vitrinite reflectance. More recent attempts to assess the thermal maturity of the Bakken Fm. black shales have measured and converted SBRo to vitrinite reflectance equivalent (VRE). However, samples selected for SBRo by some previous workers have included heterogenous, granular as well as high reflecting SB samples, which introduce error in the measurements. As such, reported reflectance values are most likely lower than they would be if smooth, homogenous solid bitumen with no inclusions were measured. For this project, smooth and homogenous SB was measured to produce consistent and reliable VRE values to assess the thermal maturity gradient from the Bakken Fm. basin margins to the depocenter. Blue-light fluorescence petrography was done to support thermal maturity assessments. Results from SBRo, Rock-Eval Ro, VRE, and blue-light fluorescence observations suggest that cores from the current study range from early oil window into condensate, wet gas.

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I. An isothermal titration microcalorimeter having a colume of 4 ml and capable of temerature control to ±2 x 10-5°C is described. Major components include a constant temperature water bath controlled to ±3 x 10-4°C, a platinum reation vessel, and an isothermal control circuit consisting of constant Peltier thermoelectric cooling and variable Joule heating controlled by a thermistor in an AC Wheatstone bridge circuit. The calorimeter was tested by measuring the heat of ionization of water and was found to produce data accurate to ± 0.1% where small samples are used such as in the investigation of many biological systems.