Miracle-dz/UniFAR-FTUs huggingface dataset:
Long‐lived deformation in the southern Mississippi Embayment revealed by high‐resolution seismic reflection and sub‐bottom profiler data

Three high‐resolution seismic reflection profiles and two sub‐bottom profiler sections acquired along the Mississippi River in southern‐Central U.S. image deformation in post‐Paleozoic sediments. The northernmost profile images two faults offsetting Cretaceous through at least Eocene Cane River reflectors, interpreted to strike northwest and to be part of the Arkansas River fault zone. The central profile shows a down‐to‐the‐north fault, displacing Cretaceous and Paleocene Midway Group reflectors by ~210 m and ~160 m, respectively. The fault is interpreted as the northern edge fault of the Monroe Uplift, a Late Cretaceous uplift associated with igneous intrusions. The southernmost profile displays a down‐to‐the‐south fault, offsetting Cretaceous and Paleocene‐Eocene Wilcox Group reflectors by ~125 m and ~32 m, respectively. Tilted reflectors in the first 80 m indicate Eocene‐Oligocene activity of the fault, although Quaternary activity cannot be ruled out. Quaternary tectonic activity is proposed for a series of faults that offset shallow (<40 m depth) Eocene sequences and the base of the Quaternary alluvium as imaged on two sub‐bottom profiler sections. These shallow faults are imaged in the vicinity of Holocene earthquake‐induced liquefaction fields, corroborating the evidence for recent tectonic activity in the area. The spatial coincidence of the imaged faults with the inferred location of the Alabama‐Oklahoma transform strongly argues toward a long‐lived influence of this Precambrian continental margin in focusing tectonic activity in the southern U.S. by controlling the reactivation of Triassic‐Jurassic syn‐rift basement structures and guiding the emplacement of Late Cretaceous igneous intrusions and the location of Cenozoic deformation.
Ozone trend in the northern hemisphere: A numerical study

A two-dimensional model has been used to study the possible effects of heterogeneous chemistry on the ozone concentration in the northern high latitudes. The model uses a diabatic circulation which is consistent with the calculated ozone. The temperature field is prescribed in such a way to realistically reproduce the thermal conditions in the polar lower stratosphere during the winter season. A complete chemical code is included that produces a realistic nitric acid concentration and then the formation of polar stratospheric clouds of nitric acid tri-hydrate particles. NOx and ClOx families are explicitly predicted as a function of time-dependent N2O, CH4 and CFC mixing ratios from the simulated year 1960 until 2000. The increase of the total chlorine amount in the stratosphere is shown to be a possible explanation for the observed trend of ozone depletion in the high-latitude northern region. The presence of polar stratospheric clouds is found to be important for the seasonal behavior of the ozone secular trend.
Geologic constraints on the existence and distribution of West Antarctic subglacial volcanism

Strong and abundant magnetic anomalies imaged beneath the West Antarctic Ice Sheet by aerogeophysical surveys have been interpreted as evidence of widespread Late Cenozoic basaltic volcanism, perhaps even a large igneous province. Petrological and geochemical composition of subglacial sediment samples from West Antarctica supports crustal provenance and does not provide positive evidence for the existence of the proposed mafic Late Cenozoic large igneous province. The only two identified basaltic pebbles, out of a total of >500 examined pebbles, are of Mesozoic to Cambrian age. We conjecture that the subglacial large igneous province does not exist or is blanketed by an at least Miocene age sedimentary drape.
Incremental relational lenses

Lenses are a popular approach to bidirectional transformations, a generalisation of the view update problem in databases, in which we wish to make changes to source tables to effect a desired change on a view. However, perhaps surprisingly, lenses have seldom actually been used to implement updatable views in databases. Bohannon, Pierce and Vaughan proposed an approach to updatable views called relational lenses, but to the best of our knowledge this proposal has not been implemented or evaluated to date. We propose incremental relational lenses, that equip relational lenses with change-propagating semantics that map small changes to the view to (potentially) small changes to the source tables. We also present a language-integrated implementation of relational lenses and a detailed experimental evaluation, showing orders of magnitude improvement over the non-incremental approach. Our work shows that relational lenses can be used to support expressive and efficient view updates at the language level, without relying on updatable view support from the underlying database.
A comparison of unsupervised neural networks and k-means clustering in the analysis of multi-element stream sediment data

Isolation of complex patterns of correlation between variables, association among samples and anomaly identification, through conventional parametric multivariate statistical procedures, may be obscured by the presence of multivariate outliers and non-normal variable distributions. Procedures such as k-means clustering generally require substantial data pre-processing. Unsupervised neural networks (UNN) have the capacity to cluster multivariate data, using a modified form of the standard unsupervised Kohonen self-organizing map that is non-linear, non-parametric, rapid and robust. The number of clusters into which samples are allocated is determined by the unsupervised neural network and is directly dependent upon the original input data. UNN and k-means clustering was performed on stream sediment geochemical data from 1670 sub-catchments in the northeast region of New South Wales. Both methods produced clusters for the feldspar-associated elements that were closely related to sub-catchment geology and topography. UNN clustering revealed more subtle variations within the major lithological groups. UNN clustering of Cu–Pb–Zn produced ten main clusters and identified 26 anomalies, that were mainly from sub-catchments, containing significant base metal mineralization occurrences. K-means clustering of transformed Cu–Pb–Zn yielded five major clusters and only 19 anomalies. Progressive increase in k from eight to 20 did not substantially alter the k-means classification of samples between common groups and anomalies. Some catchments identified only as anomalous by UNN clustering contain known base metal mineralization.
Ocean Turbulence. Part II: Vertical Diffusivities of Momentum, Heat, Salt, Mass, and Passive Scalars

Abstract A Reynolds stress–based model is used to derive algebraic expressions for the vertical diffusivities Kα(α = m, h, s) for momentum, heat, and salt. The diffusivities are expressed as Kα(Rρ, N, RiT, ϵ)in terms of the density ratio Rρ = αs∂S/∂z(αT∂T/∂z)−1, the Brunt–Vaisala frequency N2 = −gρ−10∂ρ/∂z, the Richardson number RiT = N2/Σ2 (Σ is the shear), and the dissipation rate of kinetic energy ϵ. The model is valid both in the mixed layer (ML) and below it. Here Rρ and N are computed everywhere using the large-scale fields from an ocean general circulation model while RiT is contributed by resolved and unresolved shear. In the ML, the wind-generated large-scale shear dominates and can be computed within an OGCM. Below the ML, the wind is no longer felt and small-scale shear dominates. In this region, the model provides a new relation RiT = cf(Rρ) with c ≈ 1 in lieu of Munk's suggestion RiT ≈ c. Thus, below the ML, the Kα become functions of Rρ, N, and ϵ. The dissipation ϵ representing the physical .
Tropical Cyclone Count Forecasting Using a Dynamical Seasonal Prediction System: Sensitivity to Improved Ocean Initialization

AbstractThis study investigates the predictability of tropical cyclone (TC) seasonal count anomalies using the Centro Euro-Mediterraneo per i Cambiamenti Climatici–Istituto Nazionale di Geofisica e Vulcanologia (CMCC-INGV) Seasonal Prediction System (SPS). To this aim, nine-member ensemble forecasts for the period 1992–2001 for two starting dates per year were performed. The skill in reproducing the observed TC counts has been evaluated after the application of a TC location and tracking detection method to the retrospective forecasts. The SPS displays good skill in predicting the observed TC count anomalies, particularly over the tropical Pacific and Atlantic Oceans. The simulated TC activity exhibits realistic geographical distribution and interannual variability, thus indicating that the model is able to reproduce the major basic mechanisms that link the TCs’ occurrence with the large-scale circulation. TC count anomalies prediction has been found to be sensitive to the subsurface assimilation in the o.
Retrospective simulation of a storm event: A first step in coupled climate/hydrologic modeling

Global and regional climate models are valuable tools for assessing the effects of natural and anthropogenic perturbations to climate and hydrology. Results of a coupled regional climate and hydrologic model system, designed for the integrated assessment of climate‐hydrologic impacts at regional scales demonstrate that (a) simulated precipitation in a storm event is sensitive to the spatial resolution of the regional climate model and (b) spatial variability of precipitation and hydraulic variables must be accounted for in order to realistically capture the basin‐scale hydrologic response to a storm event. The regional climate model (with a spatial resolution of 4 to 36 km) can be driven either by global climate model output (with resolutions at the order of 100 km) or by observed climate data. The meteorological fields simulated over the mid‐Atlantic region of the USA were disaggregated to drive the basin‐scale hydrologic model (with a resolution of 1 km). With the improved treatment of spatial variability, the simulated streamflow at the basin outlet compares well with observations. These results from coupled climate‐hydrologic models at regional scales suggest that climate‐hydrology modeling studies that do not allow for spatial variability may be misleading.
A test of three soil erosion models incorporated into a geographical information system

An examination is carried out of the application of three soil erosion models, USLE/RUSLE, SLEMSA and the Morgan, Morgan and Finney method, to the Simeto catchment in Sicily, and of the differences in the results using the three models. The models are incorporated into a grid‐based geographical information system, and the results are validated qualitatively and quantitatively. The significance of the choice of method to estimate the distributed input parameters and the method to validate the quality of the models are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Impact of background and atmospheric variability on infrared hyperspectral chemical detection sensitivity

Chemical detection using infrared hyperspectral imaging systems often is limited by the effects of variability of the scene background emissivity spectra and temperature. Additionally, the atmospheric up-welling and down-welling radiance and transmittance are difficult to estimate from the hyperspectral image data, and may vary across the image. In combination, these background variability effects are referred to as "clutter. " A study has been undertaken at Pacific Northwest National Laboratory to determine the relative impact of atmospheric variability and background variability on the detection of trace chemical vapors. This study has analyzed Atmospheric Emitted Radiance Interferometer data to estimate fluctuations in atmospheric constituents. To allow separation of the effects of background and atmospheric variability, hyperspectral data was synthesized using large sets of simulated atmospheric spectra, measured background emissivity spectra, and measured high-resolution gas absorbance spectra. The atmosphere was simulated using FASCODE in which the constituent gas concentrations and temperatures were varied. These spectral sets were combined synthetically using a physics model to realize a statistical synthetic scene with a plume present in a portion of the image. Noise was added to the image with the level determined by a numerical model of the hyperspectral imaging instrument. The chemical detection performance was determined by applying a matched-filter estimator to both the on-plume and off-plume regions. The detected levels in the off-plume region were then used to determine the noise equivalent concentration path length (NECL), a measure of the chemical detection sensitivity. The NECL was estimated for numerous gases and for a variety of background and atmospheric conditions to determine the relative impact of instrument noise, background variability, and atmospheric variability.
A Reflective Account of a Working Fortnight in Bulgaria with 12 Post-graduate Student Teachers of English and Geography

This paper seeks to describe, explore and elucidate my own and my student colleagues' thoughts and feelings during a British Council funded project involving a working visit to Bulgaria for 12 student teachers of English and geography during the summer of 1998. In particular, I examine the feelings of 'otherness' widely experienced, finding in Shakespearian theatre a suitably apt metaphor. Other intercultural and interdisciplinary dimensions are also noted, drawing on the journals of the party, and I go on to suggest tentative conclusions about the value of the project in developing understanding of diverse cultures and disciplines for students about to embark upon their teaching careers.
Participating or Not Participating? A Sociomaterial Perspective of the Embeddedness of Online Communities in Everyday Life

Online communities are increasingly becoming a venue for socializing, engaging in politics, and conducting business. Ironically, the same enabling social media technology is encroaching into everyday life and reconfiguring relations of participation. Yet, while participation in online communities has been widely studied empirically, theoretical aspects of this social phenomenon need further investigation. This paper uses a sociomaterial perspective to further develop theoretical explanation of participation in online communities and the impacts of not participating online. A sociomaterial view of online community participation decenters the human participant and recognises the agency of technology, thus creating a richer understanding than epistemological paradigms. Using converging hermeneutic circles, the paper first reviews literature for evidence of sociomaterial applications to online community research, and then proposes a framework for expressing participation in online communities from a sociomaterial perspective. Subsequently, implications of the findings and the potential for future studies are discussed.
Recent increase in the length of the melt season of perennial Arctic sea ice

General circulation models predict that greenhouse gas induced global warming will be amplified in the Arctic as a result of temperature‐albedo feedback. Whilst recent observations of decreasing Arctic sea ice extent are consistent with this scenario, the possibility that such a trend is attributable to local effects at the ice margins rather than to atmospheric warming cannot be dismissed. In the absence of direct air temperature measurements, warming over Arctic sea ice may be inferred from an increasing duration of the summer melt season. Analysis presented here of the dates of spring melt and autumn freeze‐up observed over a large fraction of perennial Arctic sea ice using passive microwave data from the SMMR and SSM/I from 1979 to 1996 reveals an increase of 5.3 days (8%) per decade in the number of melt days per summer.
Resistivity imaging to determine clay cover and permeable units at an ex-industrial site

A previous geophysical and invasive site investigation over an ex-industrial site near the Forth Estuary, Edinburgh, identified a network of subsurface oil-pipes and shallow contaminants. A subsequent resistivity survey has now been conducted to determine possible contaminant migration pathways. Resistivity images measured along 28 profiles have been inverted to obtain resistivity models and their collation has enabled a pseudo three-dimensional resistivity image of the site to be constructed. Shallow subsurface resistivities indicate that the majority of the site is covered by a layer of clay, approximately 5-10 m thick, typically regarded as sufficient for containing contaminants within the near surface. However in one region the clay layer is shown to be thin and underlain by permeable sandstone thus presenting a possible pathway for downward migration of fluids. Resistivity values at greater depths infer the existence of several sandstone units and faults that may aid the transportation of contaminants away from the site. There is particular concern that pathways may exist that allow the transportation of contaminants towards the Forth Estuary. A revision of the local geology for the site to include the faulted sandstone has been suggested.
Iron content and solubility in dust from high-alpine snow along a north-south transect of High Asia

ABSTRACT This study describes the dissolved and insoluble iron fraction of dust (mineral aerosol) in high-alpine snow samples collected along a north-south transect across High Asia (Eastern Tien Shan, Qilian Shan, and Southern Tibetan Plateau). This dust provides the basic chemical properties of mid- and high-level tropospheric Asian dust that can supply the limiting iron nutrient for phytoplankton growth in the North Pacific. The iron content in Asian dust averages 4.95% in Eastern Tien Shan, 3.38–5.41% along Qilian Shan and 3.85% in the Southern Tibetan Plateau. The iron fractional solubility averages about 0.25% in Eastern Tien Shan, 0.05–2% along Qilian Shan and 1.5% in the Southern Tibetan Plateau. Among the controlling factors that can affect iron solubility in Asian dust, such as dust composition and particle grain size, acidity seems to be the most significant and can increase the iron solubility by one or two orders of magnitude with acidification of pH=0.66. Our results reveal that iron solubility of dust in the remote downwind sites is higher than that in high-alpine snow, confirming the strong pH-dependence of iron solubility, and indicating that Asian dust shows a large variation in iron solubility on a regional scale.
On the Response of the Ocean to a Moving Storm: The Nonlinear Dynamics

Abstract A novel and efficient numerical method is used to investigate the nonlinear equations of motion for the upper layer of a two-layer ocean in which the lower layer is infinitely deep and at rest. The efficiency is achieved by seeking solutions that are in a steady state, translating in equilibrium with the storm. Oscillations are found in the wake of the storm. Two features of the response are attributed to the nonlinear terms in the equation of motion: 1) a rapid transition from a maximum in the downwelling phase, to a maximum in the upwelling phase of each oscillation, followed by a gradual relaxation to the next downwelling maximum; and 2) a displacement of the maximum response, usually to the right of the storm track, by ∼40 km. It is shown that the horizontal pressure gradient terms can be neglected from the momentum equations for “fast”, “large” storms, in which case a Lagrangian integration can be performed, following fluid particles. This enables feature 1) to be attributed to the along-tra.
Whose story is it anyway? How improv informs agency and authorship of emergent narrative

Within the field of interactive digital storytelling, one goal pursued is to build highly interactive fictional worlds in which a user can have the first-person experience of being a character in a story. The story events should unfold based in part on the user’s actions. This introduces a story representation challenge because branching narrative representations used in the games industry are insufficient. Story content must be expressed using novel procedural and generative (AI-based) representations. Emergent narrative is one approach proposed by the field to create this kind of experience. In this approach, the storyworld is inhabited by a collection of intelligent, autonomous agents, each playing the role of a story character. As in dramatic improvisation, the story is not scripted, but emerges based on the interactions of these characters with each other and with the storyworld they inhabit. This thesis presents conceptual and technical contributions situated within the emergent narrative approach. In order to better understand user agency and authorship of emergent narrative, we took lessons from the theory and practice of dramatic improvisation. User agency in emergent narrative was explored using a human-only, chat-based experiment. Improvisers were given the task to provide participants with an engaging experience as a character in an improvised story. To explore authorship of emergent narrative, we developed The Virtual Storyteller, a story generator based on the emergent narrative approach. Authoring experiments led to the identification of an iterative, improvisational style of authoring in which the emergent properties of the system affect the creative process. Dramatic improvisation also informed character agent modeling. A distinction was proposed between two tightly coupled roles that the agent plays: that of a self-interested character in the storyworld, and that of a drama-interested actor. Modeled after human improvisers, the agents were given the means to delay decisions about the details of the storyworld they inhabit until they became relevant to the unfolding narrative.
ESTIMATION OF DEPTH TO CONDUCTORS BY THE USE OF ELECTROMAGNETIC TRANSIENTS

The transient response of a layered structure to plane wave excitation can be considered to be composed of a series of waves and a ground wave. For the case of a half-space of conductivity σ and permeability μ the maximum in the electric field is found at a depth z and time t when t=z2σμ/2. This formula can be used to estimate the depth to a buried horizontal conductor with an accuracy that depends upon the resistive contrast at the conductor's surface. The above ray type of solution can be converted to a solution composed of a number of modes by the use of a Poisson transform and the transformed solutions yield decay constants that are consistent with the previously reported results. In the case of a finite source, the maximum in the electric field is strongly directed. The direction depends upon the geometry of the source and the air-earth interface. Although the maximum varies with direction it can be shown that in some directions similar laws to that above are valid. The depth to a conductor can be estimated from the early part of the transients when the ground wave is removed. The removal of the ground wave from the transient is facilitated by the use of an apparent conductivity formula. Although these results were obtained under restrictive conditions they do provide some insight into the electrical transients that are encountered by studying more complex models.