Miracle-dz/UniFAR-FTUs huggingface dataset:
Control of detachment dip on drainage development in regions of active fault-propagation folding

We have studied drainage development on active folds by using a numerical model that couples the kinematics of fault-propagation folding to a physical description of surface processes. Modeling results suggest that the dip of the underlying detachment exerts a major control on drainage development. For a nonzero detachment dip, the lateral displacement gradient sets up an axial slope behind the growing fold that diverts drainage so that the fold is shielded from rivers with large incision capacity. In this case, the characteristic fault-segment length, rather than the relative rates of fold uplift and incision, may control the spacing of transverse streams. We apply our model to the foothills of the Nepal Himalayas and suggest that striking differences in drainage patterns between central and western Nepal are controlled to a first order by variations in the dip of the underthrusting Indian plate.
Integrated Use of Seismograph and Strong-Motion Data to Determine Soil Amplification: Response of the Fraser River Delta to the Duvall and Georgia Strait Earthquakes

We present a new method to estimate site amplification, in which re- gional seismographic data are used to constrain the input motions to the soil profile. The "empirical-inferred" amplification is determined as the ratio of the Fourier spec- trum of the recorded motion on soil to the spectrum of the inferred input motion at the underlying bedrock interface. The method is demonstrated for sites on the Fraser River Delta, British Columbia (B.C.), that recorded the 1996 M 5.1 Duvall, Wash- ington, and 1997 M 4.3 Georgia Strait, B.C., earthquakes. Regional seismographic recordings on rock sites are used to determine the apparent source spectra of these events. These spectra are attenuated to sites in the Fraser River Delta, then input to a specified soil profile. We compare the empirical-inferred amplification to alternative estimates of the soil amplification based on (1) the quarter-wavelength approach and (2) the assumption that the amplification is approximately equal to the observed H/V ratio. The empirical-inferred amplification estimates are grossly consistent with the theoretical amplification estimates, but have larger peaks at specific frequencies, probably due to resonant effects not accounted for in the quarter-wavelength ap- proach. The H/V ratio appears to be a simple and useful first approximation to the site response. The Fraser River Delta amplifies weak motions by factors of three to six over a broad frequency range, from 0.2 to 4 Hz. High-frequency motions (f 10 Hz) are attenuated. The long-period amplifications pose a serious concern in the event of strong earthquake shaking from large earthquakes. A useful by-product of the analysis is the determination of apparent source spectra for the events. The apparent source spectrum of the Georgia Strait earthquake is in good agreement with the Brune point-source model, with a stress drop of approxi- mately 45 bars. The apparent source spectrum of the slightly larger Duvall earthquake is in reasonable agreement with the Brune model, with a stress drop of about 70 bars; however, for the Duvall earthquake there is evidence of a sag in spectral amplitudes, relative to the Brune model, at intermediate frequencies (0.3 to 1 Hz). This inter- mediate-frequency sag is an expected result of source complexity; it is well dem- onstrated by the broadband seismic data.
An Exact Method for Characterization of Grain Shape

ABSTRACT Grain shape may be described as precisely as needed by Fourier series expansion of the radius about the center of mass utilizing coordinates of peripheral points. Empirical results of grains from typical samples indicate that the series contains, in partitioned form, a large amount of geologically interesting information. Consequently, previous subjective evaluations of the worth of shape variations in the solution of geologic problems are justified. The shape variable is amenable to semiquantitative graphical evaluation or may be used as data for multivariate analytical schemes. Illustrative examples show that the shape variables easily discriminate grain differences arising from geographic, stratigraphic, and process factors.
Surface Buoyancy Forcing and the Mixed Layer of the Western Pacific Warm Pool: Observations and 1D Model Results

Abstract The broad, shallow body of warm (>29°C) water found in the western tropical Pacific Ocean plays an important role in the coupled ocean-atmosphere dynamics and thermodynamics associated with the El Nino-Southern Oscillation phenomenon. Thus, it is important to understand the processes that maintain and perturb that warm pool. Measurements from a buoy moored in the center of the warm pool during the TOGA Coupled Ocean-Atmosphere Response Experiment show that the exchange of mass between the ocean and atmosphere is as important as the exchange of heat. Rain forms a shallow, buoyant layer that does not mix with the water below except during infrequent strong wind events. Using a one-dimensional mixed layer model, it is demonstrated that the rate of local precipitation governs the mixed layer depth and can thus alter the rates of change in sea surface temperature during both warming and cooling periods. The observed mixed layer depth in the warm pool is at a depth that allows for maximum warming by ca.
The Active XML project : an overview

This paper provides an overview of the Active XML project developed at INRIA over the past five years. Active XML (AXML, for short), is a declarative framework that harnesses Web services for distributed data management, and is put to work in a peer-to-peer architecture. The model is based on AXML documents, which are XML documents that may contain embedded calls to Web services, and on AXML services, which are Web services capable of exchanging AXML documents. An AXML peer is a repository of AXML documents that acts both as a client by invoking the embedded service calls, and as a server by providing AXML services, which are generally defined as queries or updates over the persistent AXML documents. The approach gracefully combines stored information with data defined in an intensional manner as well as dynamic information. This simple, rather classical idea leads to a number of technically challenging problems, both theoretical and practical. In this paper, we describe and motivate the AXML model and language, overview the research results obtained in the course of the project, and show how all the pieces come together in our implementation.
The seasonal cycle of atmospheric CO2: A study based on the NCAR Community Climate Model (CCM2)

A global three-dimensional atmospheric model, the NCAR CCM2 general circulation model, has been adapted to study the hourly to yearly variability of CO2 in the atmosphere. Features of this CCM2-based model include high spatial resolution (2.8° × 2.8° latitude/longitude), 18 vertical levels, a 15-min time step, and an explicit, nonlocal atmospheric boundary layer parameterization. The surface source/sink relationships used include exchange with the ocean, the terrestrial biosphere, biomass burning, and fossil fuel release of CO2. The timing and magnitude of the model seasonal cycle are compared to observational data for 28 sites. The seasonal cycle of atmospheric CO2 is generally well predicted by the model for most of the northern hemisphere, but estimates of the amplitude of the seasonal cycle in the southern hemisphere are overpredicted. To address this aspect more rigorously, we have used the monthly surface ocean pCO2 maps created by the Max-Planck-Hamburg ocean general circulation model to asses the ocean seasonality on the atmospheric surface CO2 seasonality. The globally averaged interhemispheric gradient in atmospheric CO2 concentrations, as computed with the chosen source/sink distributions, is a factor of two too high compared to data, and selected longitudinal bands may be up to 50% higher than the zonal mean. The high temporal resolution of this model allows the infrequent yet real extrema in atmospheric CO2 concentrations to be captured. The vertical attenuation of the seasonal cycle of atmospheric CO2 is well simulated by the boundary layer/free troposphere interaction in the model in the northern hemisphere. Conversely, an increasing amplitude of the seasonal cycle aloft is found in the midlatitude southern hemisphere indicating interhemispheric transport effects from north to south. We use two different models of the terrestrial biosphere to examine the influence on the computed seasonal cycle and find appreciable differences, especially in continental sites. A global three-dimensional chemical transport model is used to assess the production of CO2 from the oxidation of CO throughout the volume of the atmosphere. We discuss these CO + OH → CO2 + H results within the context of inverse model approaches to ascertaining the global and regional source/sink patterns of CO2. Deficiencies in the model output as compared to observational data are discussed within the context of guiding future research.
Viability of Azimuthal Variation In P-wave Moveout For Fracture Detection

Both acquisition and structure a ect the azimuthal variation of P -wave moveout. Here, assuming a fractured reservoir overlaid by a weakly anisotropic overburden, I develop an analytical expression for quantifying the interval azimuthal variation in P-wave moveout. This explains previous experimental results, offers some detailed insights into the e ects of various factors, and may help for acquisition design.
TerraSAR-X InSAR multipass analysis on Venice (Italy)

The TerraSAR-X (copyright) mission, launched in 2007, carries a new X-band Synthetic Aperture Radar (SAR) sensor optimally suited for SAR interferometry (InSAR), thus allowing very promising application of InSAR techniques for the risk assessment on areas with hydrogeological instability and especially for multi-temporal analysis, such as Persistent Scatterer Interferometry (PSI) techniques, originally developed at Politecnico di Milano. The SPINUA (Stable Point INterferometry over Unurbanised Areas) technique is a PSI processing methodology which has originally been developed with the aim of detection and monitoring of coherent PS targets in non or scarcely-urbanized areas. The main goal of the present work is to describe successful applications of the SPINUA PSI technique in processing X-band data. Venice has been selected as test site since it is in favorable settings for PSI investigations (urban area containing many potential coherent targets such as buildings) and in view of the availability of a long temporal series of TerraSAR-X stripmap acquisitions (27 scenes in all). The Venice Lagoon is affected by land sinking phenomena, whose origins are both natural and man-induced. The subsidence of Venice has been intensively studied for decades by determining land displacements through traditional monitoring techniques (leveling and GPS) and, recently, by processing stacks of ERS/ENVISAT SAR data. The present work is focused on an independent assessment of application of PSI techniques to TerraSAR-X stripmap data for monitoring the stability of the Venice area. Thanks to its orbital repeat cycle of only 11 days, less than a third of ERS/ENVISAT C-band missions, the maximum displacement rate that can be unambiguously detected along the Line-of-Sight (LOS) with TerraSAR-X SAR data through PSI techniques is expected to be about twice the corresponding value of ESA C-band missions, being directly proportional to the sensor wavelength and inversely proportional to the revisit time. When monitoring displacement phenomena which are known to be within the C-band rate limits, the increased repeat cycle of TerraSAR-X offers the opportunity to decimate the stack of TerraSAR-X data, e.g. by doubling the temporal baseline between subsequent acquisitions. This strategy can be adopted for reducing both economic and computational processing costs. In the present work, the displacement rate maps obtained through SPINUA with and without decimation of the number of Single Look Complex (SLC) acquisitions are compared. In particular, it is shown that with high spatial resolution SAR data, reliable displacement maps could be estimated through PSI techniques with a number of SLCs much lower than in C-band.
Energetic neutral atoms from Titan: Particle simulations in draped magnetic and electric fields

[1] Titan's atmosphere emits energetic neutral atoms (ENAs), which are being monitored for the first time by the Cassini spacecraft. These ENAs are generated by charge exchange processes of energetic ions with neutrals from Titan's atmosphere. In this work we investigate the morphology of the ENA emission from Titan's atmosphere with a three-dimensional model that calculates the phase space density of the charge exchanging energetic ion population in the vicinity of Titan. With the model ion distribution we calculate the resulting ENA distribution and then generate maps of the ENA emission on a sphere above Titan's atmosphere. We demonstrate that the strongly draped magnetic field lines play an essential role in shaping the ENA morphology. The ENA morphology associated with spatially constant magnetic and electric fields is distinctly different. Observations of ENAs from Titan thus can be used in turn to monitor the electrodynamically complex environment as a whole, which is otherwise only accessible with local measurements along single trajectories.
Coastal Perturbations of Marine-Layer Winds, Wind Stress, and Wind Stress Curl along California and Baja California in June 1999

Abstract Month-long simulations using the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5) with a horizontal resolution of 9 km have been used to investigate perturbations of topographically forced wind stress and wind stress curl during upwelling-favorable winds along the California and Baja California coasts during June 1999. The dominant spatial inhomogeneity of the wind stress and wind stress curl is near the coast. Wind and wind stress maxima are found in the lees of major capes near the coastline. Positive wind stress curl occurs in a narrow band near the coast, while the region farther offshore is characterized by a broad band of weak negative curl. Curvature of the coastline, such as along the Southern California Bight, forces the northerly flow toward the east and generates positive wind stress curl even if the magnitude of the stress is constant. The largest wind stress curl is simulated in the lees of Point Conception and the Santa Ba.
Do Energy‐Based PET Models Require More Input Data than Temperature‐Based Models? — An Evaluation at Four Humid FluxNet Sites

It is well established that wet environment potential evapotranspiration (PET) can be reliably estimated using the energy budget at the canopy or land surface. However, in most cases the necessary radiation measurements are not available and, thus, empirical temperature‐based PET models are still widely used, especially in watershed models. Here we question the presumption that empirical PET models require fewer input data than more physically based models. Specifically, we test whether the energy‐budget‐based Priestley‐Taylor (P‐T) model can reliably predict daily PET using primarily air temperature to estimate the radiation fluxes and associated parameters. This method of calculating PET requires only daily minimum and maximum temperature, day of the year, and latitude. We compared PET estimates using directly measured radiation fluxes to PET calculated from temperature‐based radiation estimates at four humid AmeriFlux sites. We found good agreement between P‐T PET calculated from measured radiation fluxes and P‐T PET determined via air temperature. In addition, in three of the four sites, the temperature‐based radiation approximations had a stronger correlation with measured evapotranspiration (ET) during periods of maximal ET than fully empirical Hargreaves, Hamon and Oudin methods. Of the three fully empirical models, the Hargreaves performed the best. Overall, the results suggest that daily PET estimates can be made using a physically based approach even when radiation measurements are unavailable.
The effect of wilting of herbage on silage composition and its feeding value for milk production

A randomized block experiment was used to assess the effects of wilting of herbage prior to ensiling. Three silages, each a composite of three harvests taken over the season, were prepared by ensiling herbage as unwilted, medium-wilted or high-wilted material with mean dry-matter contents in the resulting silages of 192, 254 and 455g/kg respectively. The silages were ensiled in bunker silos using the same harvesting machinery and with formic acid applied at the rate of 2 81/t of herbage. The silages were offered to 81 January- and February-calving cows from the 8th day post partum until going to pasture on 27 April, with a mean period on treatmen t of 92 days. In addition, all animals received a fixed concentrate allowance of 7·6 kg/day. Wilting increased silage dry-matter intake, the mean intakes being 9·2, 9·4 and 10·0kg/day for the unwilted, medium-wilted and high-wilted material respectively, but resulted in a significant depression in milk yield, with the yields obtained during the final 14 days on treatment being 23·6, 21 -8 and 21·5kg/day respectively. Milk composition, live weight, body condition, total ration digestibility and nitrogen-balance data are also presented.
CONSTANT P' AND CONSTANT VOLUME FRICTION ANGLES ARE DIFFERENT

A series of undrained and drained constant p triaxial compression and extension tests were conducted on Nevada sand at a relative density of about 70%. Most drained tests exhibited a peak followed by a drop of deviatoric stress. The drop in stress corresponded to a drop in dilatancy rate and the formation of a shear band. In most undrained tests, negative pore pressures developed and deviatoric stress increased during the constant volume phase of the test. Eventually, cavitation of the pore fluid occurred and the deviatoric stress stabilized. The maximum stress ratios (and maximum mobilized friction angles) achieved in drained, constant p′ tests were significantly larger than in the constant volume portions of the undrained tests. Rowe (1969) and Bolton (1986) proposed that the peak friction angle has a component due to the critical state friction angle and a component due to the dilation rate. In undrained shear, there is no net dilation, yet the peak mobilized friction angle exceeds the critical state friction angle. The friction angle mobilized in undrained shear appears to be a function of the plastic dilation rate. The plastic dilation rate was estimated in the undrained tests by setting the sum of elastic and plastic dilation rates to zero. The difference between drained and undrained friction angles is consistent with the difference between plastic dilation rates in drained and undrained tests.
CRUSTAL LAYERS OF THE CONTINENTS AND OCEANS

It has been assumed heretofore that the relatively large phase called [P bar] in records of near-by earthquakes in the continents is the direct longitudinal wave, and that the corresponding velocity of about 5.6 km/sec is characteristic of the “granitic layer. ” This leads to contradiction with the calculated origin-time of transverse waves in earthquakes and cannot be reconciled with observations of the longitudinal waves from blasts. It seems more likely that the velocity of longitudinal waves below the sediments is about 6 km/sec, increases to 6 1/2 km/sec or more at a depth of roughly 10 km, and possibly decreases below a depth of between 10 and 15 km. Such a decrease in velocity is to be expected in rocks with an appreciable content of quartz, since in laboratory experiments a decrease of elastic constants of quartz with increasing temperature has been found approaching the temperature at which transformation from alpha- to beta-quartz occurs (corresponding to a depth of 25 km or more). At the bottom of a deeper layer with higher velocity (usually 7-7 1/2 km/sec) the Mohorovicic discontinuity at a depth of between 30 and 40 km, but deeper under some mountain chains, forms the boundary between the simatic crustal layers and the ultra-basic material below (wave velocity 8.2 km/sec). Most earthquake foci seem to be in the hypothetical low-velocity layer. Geophysical and geological evidence indicates a greater difference between the structure of the Pacific basin and the surrounding continental areas than between the bottom of the Atlantic or Indian oceans and the surrounding shelves or continents. In the Pacific, the surface layers seem to consist of sediments, erupted and perhaps some simatic material. Below them is probably ultra-basic material with a boundary (Mohorovicic discontinuity) at a depth of only a few kilometers. In the Atlantic Ocean (and probably similarly the Indian Ocean) the transition from the continents to the basins seems to be more gradual, and the Mohorovicic discontinuity seems to be at greater depth than in the Pacific but much shallower than in the continents. While at present there is no indication of extensive sialic material in the bottom of the Pacific, there may be limited areas with sialic material at least in the eastern part of the Atlantic Ocean while relatively basic simatic (but not ultra-basic) material seems to be close to the surface at least in parts of the western Atlantic basin.
Interpretation in ecotourism settings: investigating tour guides' perceptions of their role, responsibilities and training needs.

Sixty-five ecotour guides attending training workshops in Queensland and Western Australia in 2000 were surveyed to ascertain perceptions of their role and responsibilities as well as the impact of the training materials upon their practice. Although literature points to the increasing complexity of the ecotour guide's role, the findings reveal that guides themselves regard the provision of information and awareness of one's audience as paramount. Relatively less importance is placed on using interpretive techniques, minimising environmental impacts and influencing visitor attitudes and behaviour. Evaluation of the workshop training materials used in this study confirmed their success in increasing awareness of these important aspects of guiding. Guides indicated that the video/workbook training package was effective in promoting self-evaluation and reflection on their approach to guiding and after a month 67% of the group reported having changed their practices.