Miracle-dz/UniFAR-FTUs huggingface dataset:
Investigation of the impact of CO2 on water-rock interactions using sequential extractions

INVESTIGATION OF THE IMPACT OF CO2 ON WATER-ROCK INTERACTIONS USING SEQUENTIAL EXTRACTIONS by Sarah R. Beers Release of CO2 into groundwater has an impact on groundwater geochemistry, including a decrease in pH, and increases in alkalinity and cation concentrations. From an experiment in Bozeman, Montana, it was concluded that the cations were released by interactions between groundwater, CO2, and aquifer sediment. To evaluate these interactions, ions from the aquifer sediment were sequentially extracted to determine which cations and trace metals were associated with different phases in the sediment. These phases included ion exchange sites, carbonate, oxide, and sulfide minerals, and organic material. The data were then compared with the groundwater chemistry data to determine the likely reactions occurring in the aquifer with the addition of CO2. Geochemical groundwater modeling revealed that the groundwater was undersaturated with respect to calcite both before and during the addition of CO2. Thus, calcite dissolution was contributing to the groundwater chemistry. In addition to calcite dissolution, a decrease in pH in the aquifer affected ion exchange and manganese oxide dissolution. Comparisons between the sequential extraction results and groundwater chemistry showed that uranium and barium were closely related to carbonate dissolution, while magnesium and strontium were primarily contributed by ion exchange. Also, manganese oxides contributed a majority of the cobalt in the system. Ion exchange, carbonate dissolution, and manganese oxide dissolution are responsible for a majority of the groundwater geochemical changes as a result of CO2 injection.
Experimental analysis of the resolution in shallow GPR survey

Ground-penetrating radar (GPR) is a high resolution surveying method applied to civil engineering, surface geology, archaeology and other disciplines. Today, GPR is an effective technique for investigating the integrity of concrete structures. As a non destructive technique, it is particularly suited for the assessment of large structures such as prestressed concrete bridges, highways, railway tracks and tunnels. A significant parameter in GPR high frequency surveys is the horizontal resolution. This parameter indicates the capability of the method to detect anomalies and to discriminate between adjacent elements. In concrete structures analysis the horizontal resolution lead to determine the exact position of reinforcing elements. This paper presents the basics of GPR, its limits, and the experimental measurements and the signals post-processing performed in order to determine the horizontal resolution of a 1.6 GHz antenna in concrete structures assessments.
Partitioning Tracer Tests for Evaluating Remediation Performance

Partitioning tracer tests (PTTs) are being used in environmental systems for the detection and estimation of nonaqueous phase liquid (NAPL) saturations in contaminated aquifers. A series of such studies was recently conducted at Hill Air Force Base, Utah, in two hydraulically isolated test cells of an aquifer contaminated by light nonaqueous phase liquids (LNAPL). These experiments were performed before and after two remediation efforts, a complexing sugar flush (CSF) and a recirculating in‐well aeration (IWA) system. The breakthrough curves obtained from monitoring tracer concentrations in the extraction wells indicated the presence of an immiscible phase, and the LNAPL saturation values determined from the pre‐ and post‐PTTs allowed the estimation of remediation efficiencies for both test cells. These remediation efficiencies, a removal of 43% of the LNAPL for the CSF and an increase of 32% for the IWA system, are consistent with data obtained from cores collected from within the experiment zones. The apparent increase in contamination for the IWA cell is likely due to a significant change in the LNAPL distribution caused by the flow system associated with the IWA technology. Several factors influenced the interpretation of the PTT data. Physical heterogeneities at the site caused significant tailing of the tracer concentrations and required the use of a simple extrapolation technique to account for the concentrations below analytical quantification limits. Degradation affected selected nonreactive and reactive tracers, causing the overestimation and underestimation of LNAPL saturations, respectively.
Appendix: Current Publications for Non-Western Studies

T HE School of Oriental and African Studies (SOAS) in the University of London, founded in 1917, is in effect a congeries of groups of scholars engaged in area studies. It has departments of the languages and cultures of India, Pakistan, Ceylon, South East Asia and the Islands, the Far East, the Near and Middle East, Africa, and, in addition, departments of phonetics and linguistics, history, law, anthropology and sociology, and economic and political studies. The establishment of a department of geography is contemplated for the near future. Interdisciplinary seminars and other joint meetings are regularly held; these, too, tend to break down the usual interdepartmental barriers. The library of the school contains, at the time of writing, some 260,000 printed volumes and pamphlets and some 1,700 manuscripts in more than 2,500 languages. The great majority of the books are arranged on the shelves primarily by language (if it is an oriental or African one) and by country (if written in a European language), and thereafter by subject, as the case seems to demand. The library's catalogs follow the same general principle: there are author, title, and subject catalogs in separate sequences, the choice of subject headings falling primarily on language and country. The library's activities range far beyond the orbit of its parent bodies, the school and the university. The Hayter Report' declared that, in view of its general lending policy, it should be recognized as a national library for Asian and African studies. It is regularly used by some 750 members who are in no way connected with the University of London, and it lends freely both directly and through the national interlibrary loan system.
Seismic body waves in anisotropic media: synthetic seismograms

Summary. Synthetic seismograms and particle motion diagrams are computed for simple, layered Earth models containing an anisotropic layer. The presence of anisotropy couples the P, SV and SH wave motion so that P waves incident on the anisotropic layer from below produce P, SV and small-amplitude SH waves at the surface both the P velocity and the amplitudes of the converted phases vary with azimuth. Significant SH amplitudes may be generated even when the wavelength of the P wave is much greater than the thickness of the anisotropic layer. Incident SV or SH waves may each generate large amplitudes of both SV and SH motion. This strong coupling is largely independent of the degree of velocity anisotropy of the medium. The arrivals from short-period S waves exhibit S-wave splitting, but arrivals from longer period S waves superpose into a modified waveform. This strong coupling does not allow the arrival of separate phases with pure SV and SH polarization except along directions of symmetry where the motion decouples.
Efficient sampling of reference noise in a switched capacitor ΣΔ ADC

The implementation of an efficient sampling technique whereby the reference capacitor is selectively sampled within a switched capacitor /spl Sigma//spl Delta/ ADC is presented, resulting in improved thermal noise performance. When a transition occurs in the modulator feedback, the reference capacitors are not sampled but instead discharged to ground. The introduction of a do-not-sample state requires that the /spl Sigma//spl Delta/ modulator is compensated. For mid-scale inputs, the overall ADC noise is reduced by 5.6 dB, without any increase in power consumption.
GIT-Net: Generalized Integral Transform for Operator Learning

This article introduces GIT-Net, a deep neural network architecture for approximating Partial Differential Equation (PDE) operators, inspired by integral transform operators. GIT-NET harnesses the fact that differential operators commonly used for defining PDEs can often be represented parsimoniously when expressed in specialized functional bases (e.g., Fourier basis). Unlike rigid integral transforms, GIT-Net parametrizes adaptive generalized integral transforms with deep neural networks. When compared to several recently proposed alternatives, GIT-Net's computational and memory requirements scale gracefully with mesh discretizations, facilitating its application to PDE problems on complex geometries. Numerical experiments demonstrate that GIT-Net is a competitive neural network operator, exhibiting small test errors and low evaluations across a range of PDE problems. This stands in contrast to existing neural network operators, which typically excel in just one of these areas.
Flow discharge and sediment transport models for estimating a minimum timescale of hydrological activity and channel and delta formation on Mars

[1] This paper summarizes state-of-the-art models for water flow and sediment transport and suggests implications for the sediment grain size distribution, transport process, and delta formation. The flow velocity in Martian outflow channels is commonly calculated from the Manning equation, which is dimensionally incorrect and masks the large uncertainty of the reconstructed flow velocity. More modern friction predictors based on surface grain size distribution are tested on 190 rivers on Earth including moderately catastrophic events. The uncertainty for the flow velocity is a factor of 3–4. The sediment transport is commonly assumed to amount to 40% of the water flux (hyperconcentration), but this is only true for special conditions. A debris-flow origin of the channels is unlikely. Application of modern sediment transport models to typical Martian conditions indicates orders of magnitude smaller sediment fluxes dominated by bed load transport, resulting in much larger timescales for sediment emplacement in crater lake deltas and in the potential northern ocean. This is in part caused by the unexpected grain size distribution of the sediment derived from observations of landers and of delta morphologies. The implied duration of hydrological activity and channel and delta formation is of the order of 103–106 years, which is still very short on the geological timescale of Mars.
Tectonic Background of Ordos Basin and its Controlling Role for Basin Evolution and Energy Mineral Deposits

In order to study the relationship of energy mineral deposits and tectonic movements in Ordos basin, more than 82 samples were taken for determination of apatite and zircon fission tracks. Furthermore, 93 apatite and zircon fission tracks have been selected from other publications. According to these data and other geological background, the evolution of Ordos basin can be divided into 4 stages, and the reformation of the basin can be divided into 5 stages. The basin formation and development were controlled by regional geodynamics. Oil, coal, nature gas and uranium deposits were formed in deferent stages. In the same time, 140 samples were taken and analyzed by organic and inorganic geochemical methods. The results indicate that coal and source rocks generate oil and natural gas, which migrate through reservoir rocks. Oil and natural gas changed the redox conditions of sediments and let uranium accumulate in the sandstones.
A Warming-Induced Biome Shift Detected in Tree Growth of Mountain Hemlock [Tsuga mertensiana (Bong.) Carrière] Along the Gulf of Alaska

Abstract Recent observations of divergence between tree growth at high-latitude sites and temperature, as well as the decline of yellow cedar [Callitropsis nootkatensis (D. Don) Oerst. ex D.P. Little] in southeast Alaska due to warming, emphasize a need to investigate nonstationary climate response of Alaskan coastal forests to warming in other tree species. Comparison of annual tree growth in mountain hemlock [Tsuga mertensiana (Bong.) Carrière] to mean monthly temperature and precipitation data from Sitka, Alaska, from A.D. 1830s to 1990s along an elevational transect reveals nonstationarity in tree growth response to climate that suggests an ongoing biome shift. We observe a marked weakening in the positive relationship between annual growth and warmer growth season temperatures at low-elevation hemlock sites, and a concurrent increase in growth and sensitivity at higher elevations coupled with increased correlation between growth and April precipitation at all sites along our transects. As previously observed with yellow cedar, the mechanism of the hemlock biome shift may be due to an increased susceptibility of roots to damage from late frosts resulting from earlier seasonal loss of protective snowpack.
Water in Some Hypersthenic Magmas

The concentrations of $$H_{2}O$$ in inclusions of glass in phenocrysts are estimated indirectly by summation difference using electron probe microanalysis. The method probably is valid if inclusions are glassy (not devitrified) and larger than about 30 μm diameter and if more than about $$2 wt\% of H_{2}O$$ is present. Inclusions of melt may lose $$H_{2}O$$ by diffusion and/or oxidation after initial entrapment. The concentrations of $$H_{2}O$$ quenched in basaltic and andesitic glasses in olivine phenocrysts are mostly between 2 and 4 wt % for Pavlof Volcano, Alaska; Asama Volcano, Japan; Fuego Volcano, Guatemala; and Mt. Shasta, California. The revised estimate of the rate of igneous outgassing of $$H_{2}O$$ in subduction zones is twice that for fresh submarine ridge basalts and suggests that most of the $$H_{2}O $$added to oceanic crust during alteration and weathering either is recycled by some means other than magmatism or is stored deep in the earth. The $$Cl/K_{2}O$$ ratios of associated silicic glasses commonly are less than for the low-silica glasses. Silicic glasses commonly have equal or lesser concentrations of $$H_{2}O$$ compared to associated less silicic glasses. Probably many silicic hypersthenic magmas develop in vapor saturated bodies of magma within a few kilometers of the surface. Some silicic hypersthenic magmas appear to have about $$7 wt\% of H_{2}O$$ and probably developed at greater depths either by differentiation from hydrous basaltic parents or by contamination with $$H_{2}O$$-rich dacitic melts derived from partial fusion of hydrous peridotites within the crust.
Ensemble of ground subsidence hazard maps using fuzzy logic

Hazard maps of ground subsidence around abandoned underground coal mines (AUCMs) in Samcheok, Korea, were constructed using fuzzy ensemble techniques and a geographical information system (GIS). To evaluate the factors related to ground subsidence, a spatial database was constructed from topographic, geologic, mine tunnel, land use, groundwater, and ground subsidence maps. Spatial data, topography, geology, and various ground-engineering data for the subsidence area were collected and compiled in a database for mapping ground-subsidence hazard (GSH). The subsidence area was randomly split 70/30 for training and validation of the models. The relationships between the detected ground-subsidence area and the factors were identified and quantified by frequency ratio (FR), logistic regression (LR) and artificial neural network (ANN) models. The relationships were used as factor ratings in the overlay analysis to create ground-subsidence hazard indexes and maps. The three GSH maps were then used as new input factors and integrated using fuzzy-ensemble methods to make better hazard maps. All of the hazard maps were validated by comparison with known subsidence areas that were not used directly in the analysis. As the result, the ensemble model was found to be more effective in terms of prediction accuracy than the individual model.
Geophysical Delination of Mg-Rich Ultramafic Rocksfor Mineral Carbon Sequestration

A similar version of this slide presentation was given at the 2009 Society for Mining, Metallurgy, and Exploration (SME) annual meeting in Denver, Colorado, in February 2009 (McCafferty and others, 2009). This presentation was part of the “Industrial Minerals: Reducing Carbon Footprint in Industrial Minerals” session. Two other related talks were presented in the same session by Sam Krevor of Columbia University. The first talk provided a status report on mineral CO2 sequestration as an industrial process (Krevor and Lackner, 2009). The second talk presented a national-scale geologic compilation of rocks favorable for mineral CO2 sequestration in the United States (Krevor and others, 2009). This presentation, an extension of the latter talk, shows how airborne geophysical data can be used to further refine the geologic mapping of ultramafic rocks.
In situ sand state from CPT: evaluation of a unified approach at two CANLEX sites

Cet article est consacre a l'analyse des donnees de CPT dans les sables afin de deduire l'indice des vides a partir des resistances a la penetration au cone. L'on a etudie a l'interieur d'un nouveau cadre de reference deux sites de CANLEX, l'un appele site Syncrude comprenant un depot de sable de steriles relativement homogenes a Fort McMurray, Alberta, et l'autre qui est un des sites de la phase II constitue d'un depot de sable naturel dans le delta du fleuve Fraser pres du tunnel Massey en Colombie Britannique. L'approche proposee considere que la resistance en pointe normalisee des sables est reliee a un parametre d'etat normalise, au niveau initial de contrainte, et a la contrainte a l'etat critique. La methode d'interpretation fournit l'etat in situ d'un depot de sable donne, et requiert la connaissance des parametres a l'etat critique qui peuvent etre determines en laboratoire sur des echantillons reconstitues. Cependant, il est essentiel d'obtenir ces parametres sur une plage etendue de contraintes incluant les contraintes pour lesquelles le broyage des grains est produit par cisaillement. Une concordance etroite a ete obtenue sur le site de Syncrude qui est un depot relativement jeune. Cependant, l'analyse des donnees de CPT du site de Massey suggere que le vieillissement et (ou) la cimentation influencent la resistance a la penetration au cone, donc l'etat in situ, si les valeurs non corrigees du CPT sont utilisees.
On the Welfare Costs of Consumption Uncertainty

Satisfactory calculations of the welfare cost of aggregate consumption uncertainty require a framework that replicates major features of asset prices and returns, such as the high equity premium and low risk-free rate. A Lucas-tree model with rare but large disasters is such a framework. In the baseline simulation, the welfare cost of disaster risk is large—society would be willing to lower real GDP by about 20% each year to eliminate all disaster risk. In contrast, the welfare cost from usual economic fluctuations is much smaller, though still important—corresponding to lowering GDP by around 1.5% each year. *This research is supported by the National Science Foundation. I am grateful to JongWha Lee for motivating me to think about this topic. I appreciate comments from Fernando Alvarez, Marios Angeletos, John Campbell, John Cochrane, Xavier Gabaix, Francois Gourio, Lars Hansen, Greg Mankiw, Ian Martin, Casey Mulligan, and Ivan Werning. Lucas (1987, Ch. 3; 2003, section II) argued that the welfare gain from eliminating uncertainty in aggregate consumption is trivial. He got this answer by using parameters for the time series of real per capita consumer expenditure from U.S. postWorld War II macroeconomic data, along with plausible values for the coefficient of relative risk aversion. One problem with this calculation, apparent from Mehra and Prescott (1985), is that simulations with the same model and parameters do not get into the right ballpark for explaining well-known asset-pricing puzzles, such as the high equity premium and low risk-free rate. These failures with respect to asset returns suggest, as observed by Atkeson and Phelan (1994), that the model misses important aspects of consumption uncertainty. Hence, the model’s estimates of welfare effects from consumption uncertainty are likely to be inaccurate. A possibly satisfactory framework, used here, is one with rare economic disasters, as in Rietz (1988). Barro (2006) shows that this model can replicate prominent features of asset returns. Salyer (2007) demonstrates that the allowance for low-probability crash states amplifies the welfare costs computed by Lucas. The present analysis builds on this work to show that, in a rare-disasters setting, changes in consumption uncertainty that reflect shifts in the probability of disaster have major implications for welfare. Section I works out the baseline, Lucas-tree model with rare disasters. Key features are i.i. d. shocks to output growth and iso-elastic preferences. Section II computes welfare costs within this model; first for marginal changes in uncertainty and then for large changes. Section III discusses the dependence of welfare costs on the key preference parameter—the coefficient of relative risk aversion, which equals the
Sustainable Use of Ecosystem Services Under Multiple Risks – A Survey of Commercial Cattle Farmers in Semi-Arid Rangelands in Namibia

Studying the sustainable use of ecosystem services under uncertainty requires the consideration of the stochastic dynamics of the system under study, risk and time preferences, risk management strategies and normative views pertaining to sustainability. To gather this information for an important ecological-economic system, we conducted a survey of commercial cattle farmers in semi-arid rangelands of Namibia, a system that features risks on various space and time scales. Here we present a description of the research aims, design and conduction of the survey, and analyze and discuss the homogeneity and representativeness of our survey population. The survey consisted of a mail-in questionnaire and in-field experiments. We combined two existing farm-address databases, reaching 77% of the estimated 2,500 cattle farmers. The return rate of questionnaires exceeded 20%, and response rate to individual questions surpassed 95% and 90% for the majority of non-sensitive and sensitive questions, respectively. Distinct sub-sample groups within the survey population did not differ in the analyzed characteristics with the exception of ethnicity, regional location of farmland and an intentionally induced bias for residency on farm. It has turned out that we have undersampled distinct population segments of farmers, such as indigenous farmers or farmers not belonging to the main interest group of commercial cattle farming. Notwithstanding, we consider the survey to be highly successful, yielding a rich dataset which allows diverse analyses.