New Constraints on the Composition of Jupiter from Galileo Measurements and Interior Models     

Tristan Guillot  Daniel Gautier  William B. Hubbard 《Icarus》1997,130(2):534-539

Using the helium abundance measured by Galileo in the atmosphere of Jupiter and interior models reproducing the observed external gravitational field, we derive new constraints on the composition and structure of the planet. We conclude that, except for helium which must be more abundant in the metallic interior than in the molecular envelope, Jupiter could be homogeneous (no core) or could have a central dense core up to 12M_⊕. The mass fraction of heavy elements is less than 7.5 times the solar value in the metallic envelope and between 1 and 7.2 times solar in the molecular envelope. The total amount of elements other than hydrogen and helium in the planet is between 11 and 45M_⊕.  相似文献   

Strategies for waveform processing in sparker data     

Mathieu J. Duchesne  Gilles Bellefleur  Mike Galbraith  Randy Kolesar  Rick Kuzmiski 《Marine Geophysical Researches》2007,28(2):153-164

A sparker is a marine seismic impulsive source used for high-resolution seismic surveys. Sparker sources were very popular during the late 1960s and 1970s before being supplanted by small volume airguns. However, in the last 10 years there has been renewed interest in sparker technology because (1) it can be easily deployed at relatively low costs and (2) in certain areas the use of small airguns is restricted for environmental purposes. In this study a sparker source was used to assess the seismic stratigraphy of Quaternary deposits and to image the sediment/bedrock interface. Three different inverse filtering methods were tested (i.e., spiking deconvolution, match-filtering and vertical seismic profile (VSP) deconvolution) to correct the poor shot-to-shot repeatability of the source and to compress its reverberations. Results show that the matched-filter and VSP deconvolution methods, which design and apply one operator for each shot, produced comparable results, whereas the spiking deconvolution that used the same operator on all traces failed to compress the source signature properly.  相似文献   

Shale-Gas Assessment: Comparison of Gas-In-Place Versus Performance-Based Approaches   总被引：1，自引：0，他引：1  

H. Stueck  D. Houseknecht  D. Franke  D. Gautier  A. Bahr  S. Ladage 《Natural Resources Research》2016,25(3):315-329

The recent interest in exploration for shale gas increases the demand for a reliable, compatible resource assessment. Many different assessment methods are used, commonly depending on types and quantity of data available, which may lead to significantly divergent results for the same shale-gas play. This study compares results obtained using performance-based and gas-in-place methodologies to assess a well-developed and active shale-gas play (Woodford Shale, Arkoma Basin, USA) and two untested, hypothetical shale-gas plays (Shublik and Brookian, Alaska North Slope, USA). Results show that the two assessment methods produce comparable results when assessment units are identically defined and similar geological constraints are used as input parameters. Inherent uncertainties are associated with both assessment methods, and these are related to aspects of shale-gas production that are not well understood. The performance-based method relies on decline trend analysis to generate distributions of estimated ultimate recovery (EUR), and uncertainty increases in cases of short production history. The gas-in-place method requires the application of a recovery factor to estimate technically recoverable resources, and both absolute values of recovery factors and their spatial variability are poorly documented, and therefore a source of uncertainty.  相似文献   

Improving MODIS Spatial Resolution for Snow Mapping Using Wavelet Fusion and ARSIS Concept   总被引：1，自引：0，他引：1  

Sirguey  P. Mathieu  R. Arnaud  Y. Khan  M.M. Chanussot  J. 《Geoscience and Remote Sensing Letters, IEEE》2008,5(1):78-82

We propose to fuse the high spatial content of two 250-m spectral bands of the moderate resolution imaging spectroradiometer (MODIS) into its five 500-m bands using wavelet-based multiresolution analysis. Our objective was to test the effectiveness of this technique to increase the accuracy of snow mapping in mountainous environments. To assess the performance of this approach, we took advantage of the simultaneity between the advanced spaceborne thermal emission and reflection radiometer (ASTER) and MODIS sensors. With a 15-m spatial resolution, the ASTER sensor provided reference snow maps, which were then compared to MODIS-derived snow maps. The benefit of the method was assessed through the investigation of various metrics, which showed an improvement from 3% to 20%. Therefore, the enhanced snow map is of great benefit for environmental and hydrological applications in steep terrain.  相似文献   

A complete hydro-climate model chain to investigate the influence of sea surface temperature on recent hydroclimatic variability in subtropical South America (Laguna Mar Chiquita,Argentina)     

Magali Troin  Mathieu Vrac  Myriam Khodri  Daniel Caya  Christine Vallet-Coulomb  Eduardo Piovano  Florence Sylvestre 《Climate Dynamics》2016,46(5-6):1783-1798

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A Geostatistical Definition of Hotspots for Fish Spatial Distributions     

Pierre Petitgas  Mathieu Woillez  Mathieu Doray  Jacques Rivoirard 《Mathematical Geosciences》2016,48(1):65-77

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Thermal‐infrared remote sensing of surface water–groundwater exchanges in a restored anastomosing channel (Upper Rhine River,France)          下载免费PDF全文

David Eschbach  Guillaume Piasny  Laurent Schmitt  Laurent Pfister  Pierre Grussenmeyer  Mathieu Koehl  Grzegorz Skupinski  Abdelaziz Serradj 《水文研究》2017,31(5):1113-1124

Ecohydrological processes are a key element to consider in functional river restorations. In the framework of a LIFE+ European restoration program, we have investigated the potential for airborne thermal‐infrared remote sensing to map surface water–groundwater exchanges and to identify their driving factors. We focused our attention on anastomosing channels on an artificial island of the Upper Rhine River (Rohrschollen), where a new channel was excavated from the floodplain to reconnect an older channel in its upstream part. These hydraulic engineering works led to an increased inflow from the Rhine Canal. Here, we propose an original data treatment chain to (a) georeference the thermal‐infrared images in geographic information system based on visible images, (b) detect and correct data errors, and (c) identify and locate thermal anomalies attributed to groundwater inputs and hyporheic upwellings. Our results, which have been compared to morpho‐sedimentary data, show that groundwater upwelling in the new channel is controlled by riffle–pool sequences and bars. This channel is characterized by large bedload transport and morphodynamic activity, forming riffles and bars. In the old channel, where riffle–pool sequences no longer exist, due to impacts of engineering works and insufficient morphodynamic effects of the restoration, thermal anomalies appeared to be less pronounced. Groundwater inputs seem to be controlled by former gravel bars outcropping on the banks, as well as by local thinning of the low‐permeability clogging layer on the channel bed.  相似文献   

The impact of ENSO on Southern African rainfall in CMIP5 ocean atmosphere coupled climate models     

Bastien Dieppois  Mathieu Rouault  Mark New 《Climate Dynamics》2015,45(9-10):2425-2442

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Changes in large-scale controls of Atlantic tropical cyclone activity with the phases of the Atlantic multidecadal oscillation     

Louis-Philippe Caron  Mathieu Boudreault  Cindy L. Bruyère 《Climate Dynamics》2015,44(7-8):1801-1821

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The field and remote sensing analysis of the Kerguelen Archipelago structure,Indian Ocean     

Lucie Mathieu  Paul Byrne  Damien Guillaume  Benjamin van Wyk de Vries  Bertrand Moine 《Journal of Volcanology and Geothermal Research》2011,199(3-4):206-215

The Kerguelen Archipelago is part of an oceanic plateau with a complex history. Little work has been done on the tectonics of the onshore areas, even though the extensive outcrop renders the islands especially good for structural work. We present the results of three field campaigns and remote sensing analysis carried out in the main Kerguelen Island, around Val Travers valley and Mt Ross volcano (Central Plateau) and in the Rallier du Baty peninsula (SW part of the archipelago). We have mapped faults, fracture sets, and the location and geometry of intrusive bodies. We found that the plateau basalt lavas that make up most of the area are densely fractured, crossed by many veins, dykes and some small faults. This work provides a general framework for the structure of Kerguelen Archipelago that is dominated by 110°-striking faults and veins, dyke swarms and an alignment of recent central volcanoes, which have formed in N-S to NNW-SSE directed extensional stress field. The other structures are fractures, veins and dykes which strike 130–150°, 000° and 030–050°. They are likely related to transform faults of the Indian oceanic crust and to faults of the north Kerguelen Plateau (offshore basement of the archipelago). These buried structures were likely re-activated by a low magnitude stress field.  相似文献