Preliminary report on the geology of Colgrove Butte, Hettinger County, North Dakota

Colgrove Butte is a flat-topped erosional remnant with a cap of rock area of approximately 0.845 square miles, rising about 200 feet above the surrounding Missouri Plateau in northwestern Hettinger County, North Dakota. Its upper portion consists of flat lying fresh water deposits of White River (Oligocene) age, containing beds of hard limestone, marls, argillaceous limestones, calcareous clays, clays and sands. It is everywhere covered by a mantle of top soil 6 inches to 3 feet 6 inches thick. Below this topsoil, extending over approximately two-thirds of the caprock area of the butte, is a bed of hard limestone averaging one foot in thickness, which is succeeded by alternate beds of marl, argillaceous limestone and calcareous clays down to a depth of 20-25 feet from the surface. By rough calculations the weight of the uppermost limestone bed with a thickness of one foot was found to be 1,300,000 short tons, and its calcium carbonate content 80-90 percent. Bodies of rock extending three, six, and ten feet down from the bottom of the topsoil, and covering two-thirds of the butte area, were found to contain 61.5, 55.0, and 47.3 percent of calcium carbonate and weigh 3,820,000, 7,640,000, and 12,740,000 short tons respectively. Additional test holes need to be sunk into and through the caprock to determine more accurately the amount and grade of calcareous material available in the uppermost layers. Manufacture of Portland cement from calcareous material at Colgrove Butte calls for the wet process, provided that sufficient supply of water can be economically developed

Arctic-HYDRA Consortium (2010). Arctic-HYDRA: The Arctic Hydrological Cycle Monitoring, Modelling and Assessment Programme.

The Arctic-HYDRA networking activity was launched during the IPY period by representatives of national hydrological institutes and academic departments in all Arctic countries. The consortium aims to produce a new quantitative picture of the state of the Arctic Hydrological Cycle at a time when rapid Arctic warming is affecting several domains of the climate system. Other important tasks of the group include support for pan-Arctic hydrological and meteorological modelling efforts and the continuation and expansion of existing observational networks. The present report is based on material compiled and discussed during a series of workshops held by Arctic-HYDRA members in the years 2006-2009

Emergency hospital visits in association with volcanic ash, dust storms and other sources of ambient particles: a time-series study in Reykjavík, Iceland.

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked Files. This article is open access.Volcanic ash contributed significantly to particulate matter (PM) in Iceland following the eruptions in Eyjafjallajökull 2010 and Grímsvötn 2011. This study aimed to investigate the association between different PM sources and emergency hospital visits for cardiorespiratory causes from 2007 to 2012. Indicators of PM10 sources; "volcanic ash", "dust storms", or "other sources" (traffic, fireworks, and re-suspension) on days when PM10 exceeded the daily air quality guideline value of 50 µg/m3 were entered into generalized additive models, adjusted for weather, time trend and co-pollutants. The average number of daily emergency hospital visits was 10.5. PM10 exceeded the air quality guideline value 115 out of 2191 days; 20 days due to volcanic ash, 14 due to dust storms (two days had both dust storm and ash contribution) and 83 due to other sources. High PM10 levels from volcanic ash tended to be significantly associated with the emergency hospital visits; estimates ranged from 4.8% (95% Confidence Interval (CI): 0.6, 9.2%) per day of exposure in unadjusted models to 7.3% (95% CI: -0.4, 15.5%) in adjusted models. Dust storms were not consistently associated with daily emergency hospital visits and other sources tended to show a negative association. We found some evidence indicating that volcanic ash particles were more harmful than particles from other sources, but the results were inconclusive and should be interpreted with caution.Icelandic Centre for Research PhD fun

Pioneer microbial communities of the Fimmvörðuháls lava flow, Eyjafjallajökull, Iceland

Little is understood regarding the phylogeny and metabolic capabilities of the earliest colonists of volcanic rocks, yet these data are essential for understanding how life becomes established in, and interacts with the planetary crust, ultimately contributing to critical zone processes and soil formation. Here we report the use of molecular and culture-dependent methods to determine the composition of pioneer microbial communities colonising the basaltic Fimmvörðuháls lava flow at Eyjafjallajökull, Iceland, formed in 2010. Our data show that three to five months post eruption, the lava was colonized by a low-diversity microbial community dominated by Betaproteobacteria, primarily taxa related to nonphototrophic diazotrophs such as Herbaspirillum spp., and chemolithotrophs such as Thiobacillus. Although successfully cultured following enrichment, phototrophs were not abundant members of the Fimmvörðuháls communities, as revealed by molecular analysis, and phototrophy is therefore not likely to be a dominant biogeochemical process in these early successional basalt communities. These results contrast with older Icelandic lava of comparable mineralogy, in which phototrophs comprised a significant fraction of microbial communities and the non-phototrophic community fractions were dominated by Acidobacteria and Actinobacteria

Metagenomic analyses of a microbial assemblage in a subglacial lake beneath the Vatnajökull ice cap, Iceland

Skaftárkatlar are two subglacial lakes located beneath the Vatnajökull ice cap in Iceland associated with geothermal and volcanic activity. Previous studies of these lakes with ribosomal gene (16S rDNA) tag sequencing revealed a limited diversity of bacteria adapted to cold, dark, and nutrient-poor waters. In this study, we present analyses of metagenomes from the lake which give new insights into its microbial ecology. Analyses of the 16S rDNA genes in the metagenomes confirmed the existence of a low-diversity core microbial assemblage in the lake and insights into the potential metabolisms of the dominant members. Seven taxonomic genera, Sulfuricurvum, Sulfurospirillum, Acetobacterium, Pelobacter/Geobacter, Saccharibacteria, Caldisericum, and an unclassified member of Prolixibacteraceae, comprised more than 98% of the rDNA reads in the library. Functional characterisation of the lake metagenomes revealed complete metabolic pathways for sulphur cycling, nitrogen metabolism, carbon fixation via the reverse Krebs cycle, and acetogenesis. These results show that chemolithoautotrophy constitutes the main metabolism in this subglacial ecosystem. This assemblage and its metabolisms are not reflected in enrichment cultures, demonstrating the importance of in situ investigations of this environment

Increased respiratory morbidity associated with exposure to a mature volcanic plume from a large Icelandic fissure eruption.

The 2014-15 Holuhraun eruption in Iceland was the largest fissure eruption in over 200 years, emitting prodigious amounts of gas and particulate matter into the troposphere. Reykjavík, the capital area of Iceland (250 km from eruption site) was exposed to air pollution events from advection of (i) a relatively young and chemically primitive volcanic plume with a high sulphur dioxide gas (SO2) to sulphate PM (SO42-) ratio, and (ii) an older and chemically mature volcanic plume with a low SO2/SO42- ratio. Whereas the advection and air pollution caused by the primitive plume were successfully forecast and forewarned in public advisories, the mature plume was not. Here, we show that exposure to the mature plume is associated with an increase in register-measured health care utilisation for respiratory disease by 23% (95% CI 19.7-27.4%) and for asthma medication dispensing by 19.3% (95% CI 9.6-29.1%). Absence of public advisories is associated with increases in visits to primary care medical doctors and to the hospital emergency department. We recommend that operational response to volcanic air pollution considers both primitive and mature types of plumes

The astrobiology primer: An outline of general knowledge - Version 1, 2006

Peer reviewe

Photoeleastic stress analysis of four different prefabricated posts for endodontically treated teeth : a thesis submitted in partial fulfillment ... restorative dentistry, operative / by Thorsteinn Sch. Thorsteinsson.

ii, 110 leaves.http://babel.hathitrust.org/cgi/pt?id=mdp.39015018064033;view=2up;ui=fullscreen#page/n0/mode/2u

Climate Change and Energy Systems : Impacts, Risks and Adaptation in the Nordic and Baltic countries

Renewable energy sources contribute 16% of the global energy consumption and most nations are working to increase the share of renewables in their total energy budget, to reduce the dependence on fossil fuel sources. Most Nordic and Baltic countries have already surpassed the target set for EU countries by 2020, to produce 20% of energy use from renewables like hydropower, solar energy, wind power, bio-energy, ocean power and geothermal energy. This publication presents results from a comprehensive research project that investigated the effects of projected future climate change on hydropower, wind power and bioenergy in the Nordic and Baltic countries, with focus on the period 2020-2050. The research group investigated historical climate, runoff and forest growth data and produced climate scenarios for the region based on global circulation models. The scenarios were used as input in models forecasting changes in glacial meltwater production, basin-wide runoff, mean wind strength, extreme storm and flooding events and energy biomass production. Although the uncertainty in modelling results translates into increased risks for decision-making within the energy sector, the projected climate change is predicted to have a largely positive impact on energy production levels in the region, and energy systems modelling projects increased export of energy to continental Europe by 2020