Miracle-dz/UniFAR-FTUs huggingface dataset:
The Functioning of Sediment Routing Systems Using a Mass Balance Approach: Example from the Eocene of the Southern Pyrenees

Sediment routing systems link source regions undergoing erosion with depositional sinks and involve a volumetric or mass budget. Understanding how these source-to-sink systems function is key to stratigraphic prediction, but estimation of their surface sediment discharges and depositional fluxes on geological time scales is a challenging problem. We recognize a paleosediment routing system from the geological record in the mid-late Eocene Escanilla Formation and time equivalents of the tectonically active wedge-top region of the southern Pyrenees. By mapping the >200-km-long fairway of the Escanilla sediment routing system, we obtain the sediment budget and grain-size fractionation of three time intervals, each of 2.5–2.6-m.yr. duration, over the time period 41.6–33.9 Ma. Four thousand cubic kilometers of sediment, sourced principally from two feeder systems in the high Pyrenees, was deposited in a period of 7.7 m.yr. The positions of moving boundaries, characterized by rapid reduction in the percentage of gravel, sand, and fine grain-size fractions (gravel cline, gravel front, sand front), are sensitive to the dynamics of the sediment routing system. In order to understand these dynamics, total volumes of sediment sequestered as stratigraphy, together with the component volumes of gravel, sand, and fines, are transformed into a mass balance framework. Over time, there was a progressive westward progradation of coarse-grained facies driven by increasing sediment supply from the rapidly eroding Pyrenean orogen. Changes in the rate of downsystem fining of grain size, percentages of grain-size fractions in preserved stratigraphy, position of moving boundaries, and evolution of gross-depositional environments are related to variations in the volume of sediment supplied, the grain-size mix of the supply, and the spatial distribution of tectonic subsidence generating accommodation.
Pressure dependence of permeability: a model for cracked rocks

Summary We assume that permeability in crystalline rocks is mainly controlled by interconnected cracks. Following Dienes (1982), statistical distributions of cracks are introduced (crack aperture and radius distributions, spatial distribution). Percolation theory is used to describe the interconnection of cracks. At first, we assume that cracks are smooth and close elastically under pressure. In that case, permeability evolution results from both variations of crack aperture and interconnection. In a second step, crack roughness is taken into account: when asperities of rough-walled cracks make contact, the evolution of cracks is controlled by asperities indentation. Two different possibilities are then considered: modification of the flow tortuosity or modification of the crack aperture. Calculations are performed for both of these situations and we compare theoretical models with experimental results. It appears that the tortuosity effect is negligible and that the second model gives the best results and describes well the permeability decrease. Values of microstructural parameters introduced are realistic, so that it seems possible to predict the permeability evolution from the observation of microstructural parameters.
Snow cornice dynamics as a control on plateau edge erosion in central Svalbard

Snow cornices grow extensively on leeward edges of plateau mountains in central Svalbard. A dominant wind direction, a snowdrift source area and a sharp slope transition largely control the formation of snow cornices in a barren peri‐glacial landscape. Seasonal snow cornice dynamics control bedrock weathering and erosion in sedimentary bedrock on the Gruvefjellet plateau edge in the valley Longyeardalen. Air, snow and ground temperature sensors, as well as automatic time‐lapse cameras on a leeward facing plateau edge were used to study seasonal cornice dynamics. These techniques allowed for monitoring of cornice accretion, deformation and collapse/melting in great detail. The active layer of the top plateau edge is characterized by high moisture content due to rain before freeze‐up in autumn and cornice meltdown during spring thaw. Thus frost weathering there can be very efficient in this otherwise cold and dry environment. Within the first autumn snowstorms, a vertical fully developed cornice was in place (190 cm thick). The backwall surface beneath the thickest part of the cornice remained in the ice segregation ‘frost cracking window’ for almost nine months. Highly weathered rock material from the plateau edge is thus incorporated into the cornice during cornice accretion. Brittle snow deformation leads to the opening of cornice tension cracks between the cornice mass and the snowpack on the plateau. These cracks are a prerequisite for cornice collapses, and often trigger cornice fall avalanches on the slope beneath. In these open cornice tension cracks, weathered rock debris, plucked from the plateau edge, can be visible, demonstrating the erosional property of the cornices. The cornice will either collapse or melt, resulting in suspended sediment transport downslope by cornice fall avalanche or release as rock fall respectively. Therefore, cornices both promote and trigger high weathering rates on Gruvefjellet, and thus control presently the development of the rockwall free faces and the talus cones. Copyright © 2012 John Wiley & Sons, Ltd.
Relationship between N2O and CO2 emissions from the Amazon Basin

Soils of tropical forests are the most important source of atmospheric N2O from natural ecosystems, but the extant flux estimates are based on a relatively small number of field measurements and simple extrapolation procedures. We present an empirical relationship between N2O and CO2 emissions from soils of Amazon tropical forest based on seven years of field measurements in Rondônia, Brazil. This relationship can be combined with estimates of soil CO2 emissions from existing biogeochemistry models to produce estimates of N2O emissions for tropical forest regions.
Type Pi Magnetic field pulsations at very high latitudes and their relation to plasma convection in the magnetosphere

Type Pi (broadband) magnetic field pulsation activity near the dayside cusp and in the polar cap has been investigated using data recorded at Sachs Harbour (76.2°N, IL (invariant latitude)) and at Thule, Greenland (86.3°N, IL). Most of the pulsation activity observed at these sites must be classsified as type Pi, and this activity occurs mainly in midday hours. In summer, the midday Pi intensities are on the same order as at auroral oval sites in the night sector. Pi amplitudes are smaller in winter at Thule than in summer in the ratio 1∶3. Pi activity is always present at these very high latitudes in day hours in summer, with a minimum observed amplitude of 14 nT at Sachs and 5 nT at Thule in June–July, 1977. A study of isolated substorms having sharp onsets revealed a clear tendency for Pi activity to appear in the polar cap preceding the substorm, with a median lag between onset of Pi at Thule and onset of substorm near 1½ hours. We believe that this class of Pi activity indicates the presence of plasma convecting antisunwards over the polar cap. Polar cap and cusp Pi activity also tends to be seen during the substorms. The Pi pulsations appear to be caused by three-dimensional current loops that are driven by the magnetospheric electric field at times of enhanced plasma convection. The response of the current loop is closely related to the conductivity of the E region portion of the loop, and this characteristic explains the tendencies for larger Pi amplitudes to be observed in the dayside and summer time polar cap and at locations where auroral precipitation increases the E region conductivity.
Influence of subducted components on back‐arc melting dynamics in the Manus Basin

Lavas erupted in back‐arc basins afford the opportunity to explore the extent to which decompression and subduction‐related components influence partial melting in this setting. We present U‐Th‐Ra disequilibria data from 24 well‐characterized lavas from the Manus Basin behind the New Britain volcanic arc, supplemented by some additional trace element and Sr‐Nd‐Pb isotope data. The lavas range in composition from 49.6 to 57.7 wt % SiO2 and can be subdivided into those that are broadly like mid‐ocean ridge basalts (MORB) with Ba/Nb < 16 and back‐arc basin basalts (BABB) that are variably influenced by subduction components and have Ba/Nb > 16. Rifts closest to the arc are dominated by BABB, whereas both lavas types erupt further away at the Manus Spreading Center. The MORB have small 230Th excesses (up to 5%) and are displaced below the global correlation of (230Th/238U) with ridge depth. In most respects the BABB closely resemble lavas erupted along the New Britain arc front, including 238U excesses that reach 26%. The Pb isotope data can be explained by mixing of a subduction component into an Indian MORB mantle source. The Pb in the subduction component is derived from both the subducted sediment (5%) and fluids from the subducting altered Solomon Sea oceanic crust (95%), and these were mixed prior to addition to the mantle wedge. U/Th ratios, Fe3+/ΣFe, and H2O contents all increase with increasing 206Pb/204Pb. A model in which addition of the subduction component to the mantle wedge is followed by 230Th in‐growth during decompression and dynamic melting all less than 140 kyr prior to eruption can simulate the data. However, our preferred model is one of dynamic decompression melting in which subduction‐modified, more oxidized mantle had DU ≪ DTh leading to 238U excesses in contrast to unmodified mantle that yields 230Th excess. Large 226Ra excesses in some southern rift samples require addition of a fluid <8 kyr ago but elsewhere reflect melting under low‐porosity conditions.
In situ compositions of Martian volcanics: Implications for the mantle

The primary objective of this analysis is to determine the mineralogic composition of relatively pristine terrains exposed on the surface of Mars. This analysis is conducted using imaging spectrometer data acquired in 1989 by the Imaging Spectrometer for Mars (ISM) instrument that was onboard the Phobos-II spacecraft. The ISM instrument acquired some of the highest spectral (64 channels between 0.77 and 3.14 μm) and spatial resolution (≈22 km/pixel) observations to date of Mars, focused on the equatorial region. Relatively unaltered surfaces were identified in these data on the basis of their spectral properties (low albedo, weak spectral slope, absence of ferric absorptions), and were found in volcanic terrains of Syrtis Major, Valles Marineris, Ophir Planum, and Sinus Meridiani/Oxia Palus. Spectra representative of the diversity among terrains were extracted for detailed analysis using the Modified Gaussian Model to determine the primary mafic mineralogy, It was determined that the mafic mineralogy of the regions investigated is dominated by low-calcium and high-calcium pyroxene (LCP, HCP), and that there was homogeneity within a given region but some heterogeneity between regions in the relative abundance of LCP to HCP. The two-pyroxene mineralogy is consistent with the mineralogies of the basaltic SNC meteorites believed to have originated on Mars. Two-pyroxene volcanic mineralogies are indicative of large degrees of partial melting (e.g., komatiites) or a mantle source depleted in aluminum. Integration of these findings with previous studies of Mars and the SNC meteorites indicates that (1) the SNC mineralogies are representative of large volcanic regions of Mars with surface ages as old as 2–3 Ga, (2) the martian mantle was depleted in aluminum at least as long ago as the oldest terrain analyzed (Ophir Planum), and (3) there has been little evolution in the composition of mantle source regions as the 180 Ma SNC mineralogies are comparable to those of the oldest terrains analyzed.
Updated seismotectonic zoning scheme of Metropolitan France, with reference to geologic and seismotectonic data

This work presents the seismotectonic zoning scheme of Metropolitan France developed by the IRSN (French Institute for Radioprotection and Nuclear Safety) within the framework of its seismic hazard assessment activities. It is the outcome of many years of work following the publication of the "seismotectonic atlas" in 1993 [Grellet et al., 1993]. This scheme supports the assessment of seismic hazard by IRSN. It takes into account the most recent data concerning the deep and surface geology, as well as those related to seismotectonics and tectonic activity. It finally includes 67 surface seismotectonic zones (STZ), as well as a catalogue of 74 faults or structures (named hereafter "potential active faults") for which indications of Neogene to Quaternary displacement can be inferred. The description of the zoning scheme comes along with an estimation of the uncertainty on the boundary location between adjacent STZ. We also qualitatively determine a "relevance order" for each limit, so as to illustrate their reliability to separate regions of different seismogenic potential. Also, we attributed to the faults an indication whose purpose is to reflect the recent character of their activity, and thus their seismotectonic potential. This assessment of uncertainties was undertaken to better integrate the zoning scheme in the general approach, which arises from recent studies, namely the propagation of the uncertainties in seismic hazard evaluation, whether deterministic or probabilistic.
Applied Economics Workshop Business 33610 Spring Quarter 2010 "the Effects of Unemployment Insurance on Labor Supply and Search Outcomes: Regression Discontinuity Estimates from Germany" the Effects of Unemployment Insurance on Labor Supply and Search Outcomes: Regression Discontinuity Estimates fro

This paper evaluates the impact of large changes in the duration of unemployment insurance (UI) in different economic environments on labor supply, job matches, and search behavior. We show that differences in eligibility thresholds by exact age give rise to a valid regression discontinuity design, which we implement using administrative data on the universe of new unemployment spells and career histories over twenty years from Germany. We find that increases in UI have small to modest effects on non-employment rates, a result robust over the business cycle and across demographic groups. Thus, large expansions in UI during recessions do not lead to lasting increases in unemployment duration, nor can they explain differences in unemployment durations across countries. We do not find any effect of increased UI duration on average job quality, but show that the mean potentially confounds differential effects on job search across the distribution of UI duration. However, it appears that for a majority of UI beneficiaries increases in UI duration may lead to small declines in wages. as well as seminar participants at Columbia University and the DFG project 'flexibility in heterogenous labor markets' for many insightful comments.
Kotlassia prima Amalitzky

The skeletal material of Kotlassia prima , a primitive tetrapod from the Upper Permian of the North Dvina River in northern Russia, is described and figured in detail. The various specimens permit a nearly complete description except for the feet. Karpinskiosaurus secundus is a synonym of Kotlassia prima . The animal is definitely amphibian in nature although it may be regarded as a relict of the reptilian ancestors of the Reptilia. Kotlassia was as an adult a terrestrial form, in contrast to the contemporary Dvinosaurus. Seymouria may be an amphibian of the same kind.
Análise da exposição de trabalhadores rurais a agrotóxicos

Objective: To analyze the use and handling of pesticides by workers from ten rural communities in the city of Vitoria de Santo Antao-PE. Methods: Observational cross- sectional descriptive study was conducted from January to July 2010, through the application of a structured questionnaire to a sample of convenience. Sample size was estimated with a level of significance (α) of 5% in order to access variables on personal data, use and handling of pesticides. Results: Of 230 farm workers in the studied region, most were women (n=157; 69.2%) with incomplete elementary school level (n=130; 57%). It was observed that 141 (61.3%) respondent workers reported to use pesticides and only 3 (0.9%) applied the product under technical guidance of experts. Of the interviewees, 97 (28.3%) were unaware of the grace period, 67 (19.5%) unaware of recycling law, 95 (27.7%) did not use personal protective equipment, 80 (23.3%) used the rivers for washing the equipment and 108 (31.5%) reused the remains of liquid preparations. Conclusions: The harmful exposure of rural workers who used pesticides and the permanent environment contamination are evidenced. Such data reflects an agricultural model that seeks productivity and financial profits without proper compliance to health promotion and quality of the environment. doi:10.5020/18061230.2013. p182
Azimuthal dependence of VLF propagation

The World Wide Lightning Location Network (WWLLN) is used to measure the normalized lightning electric field at three network stations in order to examine the sferic attenuation between the stroke and the station. The electric field measurements are normalized to the radiated very low frequency (VLF) stroke energy to allow direct comparisons of the many stroke‐station paths seen by WWLLN. Comparing past theoretical results and models show that WWLLN observes a stronger dependence of VLF propagation on magnetic azimuth compared to past work. The average attenuation over the water of eastward‐propagating sferics is found to be 1.13±0.35 dB/Mm during the day and 0.71±0.68 dB/Mm at night, with westward‐propagating sferics having average attenuation rates of 2.98±0.68 dB/Mm and 2.66±0.39 dB/Mm for day and night, respectively.
Inverse modeling of carbon monoxide surface emissions using Climate Monitoring and Diagnostics Laboratory network observations

[1] A three-dimensional (3-D) inverse modeling scheme is used to constrain the direct surface emissions of carbon monoxide CO. A priori estimates of CO emissions are taken from various inventories and are included in the IMAGES model to compute the distribution of CO. The modeled CO mixing ratios are compared with observations at 39 CMDL stations, averaged over the years 1990–1996. The interannual variability of CO sources is therefore ignored. We show that the method used (time-dependent synthesis inversion) is able to adjust the surface fluxes on a monthly basis in order to improve the agreement between the observed and the modeled CO mixing ratios at the stations. The Earth surface is divided into regions. The spatial distribution of CO sources is fixed inside each of these regions. The inversion scheme optimizes the intensities of the emissions fluxes for the following processes: technological activities, forest and savanna burning, agricultural waste burning and fuelwood use, soil/vegetation emissions, and oceanic emissions. The inversion significantly reduces the uncertainties on the surface sources over Europe, North America and Asia. The most striking result is the increase (almost by a factor of 2) of CO flux from Asia in all a posteriori scenarios. The uncertainties on the Southern Hemisphere emissions remain large after the inversion, because the current observational surface network is too sparse at these latitudes. The inversion, moreover, shifts the peak in biomass burning emissions in the Southern Hemisphere by one month. This temporal shift ensures a better match of the observed and modeled CO seasonal cycle at the Ascension Island station. We also attempted to optimize the annual and global productions of CO due to methane and NMHC. With the current set of data, the scheme was not able to differentiate between these two sources, and hence only the total chemical production of CO can be optimized.
Palaeoenvironmental and palaeoecological change on the northern Tethyan carbonate platform during the Late Barremian to earliest Aptian

A major shift from Urgonian oligotrophic carbonate accumulation to orbitolinid‐rich mixed siliciclastic–carbonate deposition is observed near the Barremian–Aptian boundary in many sections both within and outside the shallow‐marine Tethyan Realm. This important facies change in the Swiss Helvetic Alps is documented here and interpreted in the context of general palaeoenvironmental change. To achieve this, a detailed micropalaeontological, sedimentological, mineralogical and geochemical study has been carried out on six sections across the upper part of the lower Schrattenkalk Member (Late Barremian), the Rawil Member (formerly ‘Lower Orbitolina Beds’, earliest Aptian) and the lowermost part of the upper Schrattenkalk Member (Early Aptian). The sediments of the Rawil Member exhibit inner‐platform facies with rudists, miliolids, orbitolinids and dasycladals to outer‐platform facies characterized by small benthic foraminifera, orbitolinids, crinoids and bryozoans. Stratigraphic trends in microfacies environments and the composition of microfossil assemblages, indicate that the Rawil Member includes a transgressive systems tract and the base of a highstand systems tract which are composed of an increasing number of parasequences in distal directions (five to nine in the sections studied here). The sea‐level rise discerned in the Rawil Member is coeval with increased detrital input and phosphorus burial, with maximum values up to 80 times and 21 times the background values in the subjacent part of the lower Schrattenkalk Member, respectively. Furthermore, the Rawil Member records the appearance of kaolinite, indicating a change towards tropical and more humid climate conditions. This change may have led to an increase in continental weathering rates and an associated increase in detrital and nutrient fluxes towards the ocean. The phase of climate change observed near the Barremian–Aptian boundary may have been triggered by a phase of intensified volcanic activity linked with the onset of the Ontong Java large igneous province and the Rawil Member may be the expression of a precursor episode to Oceanic Anoxic Event 1a in the shallow‐marine environment.