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Auteur Jean-Philippe Avouac |
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Affiner la recherche Interroger des sources externesPotential and limitation of PlanetScope images for 2-D and 3-D Earth surface monitoring with example of applications to glaciers and earthquakes / Saif Aati in IEEE Transactions on geoscience and remote sensing, vol 60 n° 10 (October 2022)
Titre : Potential and limitation of PlanetScope images for 2-D and 3-D Earth surface monitoring with example of applications to glaciers and earthquakes Type de document : Article/Communication Auteurs : Saif Aati Année de publication : 2022 Article en page(s) : n° 4512919 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse de scène 3D
[Termes IGN] artefact
[Termes IGN] image PlanetScope
[Termes IGN] modèle de déformation des images
[Termes IGN] modèle par fonctions rationnelles
[Termes IGN] séisme
[Termes IGN] surveillance géologiqueRésumé : (auteur) The Planet PlanetScope (PS) CubeSat constellation acquires high-resolution optical images that cover the entire surface of the Earth daily, enabling an unprecedented capability to monitor the Earth’s surface changes. However, our analysis reveals artifacts of the geometry of PS images related to the imaging system and processing issues, limiting the usability of these data for various Earth science applications, including the monitoring of glaciers, dune motion, or the measurement of ground deformation due to earthquakes and landslides. Here, we analyze these artifacts and propose ways to remediate them. We use two examples to evaluate the data and assess the performance of our proposed approaches. The first is the ground deformation caused by the 2019 Ridgecrest earthquake sequence, California, USA, and the second is the 2018–2019 surge of the Shisper glacier in the Karakorum. Using an image correlation technique, we show that PS images exhibit several geometric artifacts, such as scene-to-scene misregistration, inconsistence geolocation accuracy between spectral bands, and topographic artifacts. Altogether, these artifacts make a quantitative analysis of ground displacement difficult and inaccurate. We present a method that remediates most of these geometric artifacts. In addition, we propose a framework for selecting the most appropriate images and a procedure for refining the rational function model (RFM) of unrectified images to monitor surface displacements and topography changes in 3-D. These tools should enhance the use of PS images for Earth science applications. Numéro de notice : A2022-951 Affiliation des auteurs : UGE-LASTIG+Ext (2020- ) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2022.3215821 Date de publication en ligne : 19/10/2022 En ligne : https://doi.org/10.1109/TGRS.2022.3215821 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103278
in IEEE Transactions on geoscience and remote sensing > vol 60 n° 10 (October 2022) . - n° 4512919[article]
Titre : Understanding the geodetic signature of large aquifer systems: Example of the Ozark plateaus in central United States Type de document : Article/Communication Auteurs : Stacy Larochelle, Auteur ; Kristel Chanard Année de publication : 2022 Article en page(s) : n° e2021JB023097 Note générale : bibliographie - financial support :
PGSD‐3‐517078‐2018, Natural Sciences and Engineering Research Council of Canada
2019‐2020 STEM Chateaubriand Fellowship, Office for Science and Technology of the Embassy of France in the United States
IPGP contribution #4232, Institut de Physique du Globe de ParisLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] analyse en composantes indépendantes
[Termes IGN] aquifère
[Termes IGN] déformation de la croute terrestre
[Termes IGN] données GNSS
[Termes IGN] données GRACE
[Termes IGN] élasticité
[Termes IGN] Etats-Unis
[Termes IGN] hydrogéologie
[Termes IGN] surcharge hydrologiqueRésumé : (auteur) The continuous redistribution of water involved in the hydrologic cycle leads to deformation of the solid Earth. On a global scale, this deformation is well explained by the loading imposed by hydrological mass variations and can be quantified to first order with space-based gravimetric and geodetic measurements. At the regional scale, however, aquifer systems also undergo poroelastic deformation in response to groundwater fluctuations. Disentangling these related but distinct 3D deformation fields from geodetic time series is essential to accurately invert for changes in continental water mass, to understand the mechanical response of aquifers to internal pressure changes as well as to correct time series for these known effects. Here, we demonstrate a methodology to accomplish this task by considering the example of the well-instrumented Ozark Plateaus Aquifer System (OPAS) in the central United States. We begin by characterizing the most important sources of groundwater level variations in the spatially heterogeneous piezometer dataset using an Independent Component Analysis. Then, to estimate the associated poroelastic displacements, we project geodetic time series corrected for hydrological loading effects onto the dominant groundwater temporal functions. We interpret the extracted displacements in light of analytical solutions and a 2D model relating groundwater level variations to surface displacements. In particular, the relatively low estimates of elastic moduli inferred from the poroelastic displacements and groundwater fluctuations may be indicative of aquifer layers with a high fracture density. Our findings suggest that OPAS undergoes significant poroelastic deformation, including highly heterogeneous horizontal poroelastic displacements. Numéro de notice : A2022-944 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1029/2021JB023097 Date de publication en ligne : 15/02/2022 En ligne : https://doi.org/10.1029/2021JB023097 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103155
in Journal of geophysical research : Solid Earth > vol 127 n° 3 (March 2022) . - n° e2021JB023097[article]
Titre : Monitoring and modeling of the Sacramento Valley aquifer (California) using geodetic and piezometric measurements Type de document : Article/Communication Auteurs : Stacy Larochelle, Auteur ; Kristel Chanard Editeur : Washington DC [Maryland - Etats-Unis] : American Geophysical Union AGU Année de publication : 2022 Conférence : AGU 2022, Fall meeting, American Geophysical Union Fall Meeting 12/12/2022 16/12/2022 Chicago Illinois - Etats-Unis Importance : n° NS23A-06 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] aquifère
[Termes IGN] Californie (Etats-Unis)
[Termes IGN] données GNSS
[Termes IGN] hydrogéologie
[Termes IGN] surveillance hydrologiqueRésumé : (auteur) Changes in groundwater levels associated with hydroclimatic variations and anthropogenic water extraction can deform the solid Earth, both elastically and inelastically. Satellite-based geodetic techniques which measure the Earth’s surface displacements can thus be used to track changing conditions in aquifer systems. However, accurately extracting groundwater-induced deformation signals still poses a challenge as geodetic techniques like GNSS and InSAR also record noise, systematic errors and other sources of deformation. In this study, we take advantage of the relatively dense in situ groundwater monitoring network of the Sacramento Valley aquifer in California to constrain its deformation and hydromechanical properties. We start by characterizing the main seasonal and multiannual fluctuations in groundwater levels with an Independent Component Analysis (ICA) and exploit the resulting temporal signature to extract the associated deformation field from GNSS and InSAR time series. We then develop a poroelastic model of the aquifer to invert for its elastic storage capacity and estimate the respective contributions of elastic and inelastic processes to long-term subsidence. Our modeling also suggests that depth-dependent elastic properties are necessary to explain the spatial distribution of horizontal poroelastic displacements measured by GNSS. This work has important implications for the sustainable management of heavily-stressed Californian aquifers but also serves as a calibration between in situ and remote sensing techniques, which is essential for the successful deployment of satellite-based groundwater monitoring in areas with sparse field-based instrumentation. Numéro de notice : C2022-053 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Communication nature-HAL : ComSansActesPubliés-Unpublished DOI : sans En ligne : https://agu.confex.com/agu/fm22/meetingapp.cgi/Paper/1093662 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103158
Titre : Understanding the geodetic signature of large aquifer systems: Example of the Ozark Plateaus in Central United States Type de document : Article/Communication Auteurs : Stacy Larochelle, Auteur ; Kristel Chanard Editeur : Washington DC [Etats-Unis] : Earth and Space Science Open Archive ESSOAr Année de publication : 2021 Projets : 1-Pas de projet / Importance : 29 p. Note générale : bibliographie
soumis au Journal of Geophysical Research - Solid EarthLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] aquifère
[Termes IGN] Arkansas (Etats-Unis)
[Termes IGN] déformation de la croute terrestre
[Termes IGN] élasticité
[Termes IGN] Kansas (Etats-Unis ; état)
[Termes IGN] masse d'eau
[Termes IGN] Missouri (Etats-Unis)
[Termes IGN] Oklahoma (Etats-Unis)
[Termes IGN] série temporelle
[Termes IGN] surcharge hydrologiqueRésumé : (auteur) The continuous redistribution of water mass involved in the hydrologic cycle leads to deformation of the solid Earth. On a global scale, this deformation is well explained by redistribution in surface loading and can be quantified to first order with space-based gravimetric and geodetic measurements. At the regional scale, however, aquifer systems also undergo poroelastic deformation in response to groundwater fluctuations. Disentangling these related but distinct 3D deformation fields from geodetic time series is essential to accurately invert for changes in continental water mass, to understand the mechanical response of aquifers to internal pressure changes as well as to correct time series for these known effects. Here, we demonstrate a methodology to accomplish this task by considering the example of the well-instrumented Ozark Plateaus Aquifer System (OPAS) in central United States. We begin by characterizing the most important sources of signal in the spatially heterogeneous groundwater level dataset using an Independent Component Analysis. Then, to estimate the associated poroelastic displacements, we project geodetic time series corrected for surface loading effects onto orthogonalized versions of the groundwater temporal functions. We interpret the extracted displacements in light of analytical solutions and a 2D model relating groundwater level variations to surface displacements. In particular, the relatively low estimates of elastic moduli inferred from the poroelastic displacements and groundwater fluctuations may be indicative of surficial layers with a high fracture density. Our findings suggest that OPAS undergoes significant poroelastic deformation, including highly heterogeneous horizontal poroelastic displacements. Numéro de notice : P2021-006 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Preprint nature-HAL : Préprint DOI : 10.1002/essoar.10507870.1 Date de publication en ligne : 02/09/2021 En ligne : https://doi.org/10.1002/essoar.10507870.1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98994
Titre : A warning against over-interpretation of seasonal signals measured by the Global Navigation Satellite System Type de document : Article/Communication Auteurs : Kristel Chanard Année de publication : 2020 Projets : TOSCA / Article en page(s) : n° 1375 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] données GNSS
[Termes IGN] erreur systématique
[Termes IGN] variation saisonnièreRésumé : (auteur [introduction] In a recent study, Panda et al. claim that seasonal strain across the Himalaya indicates seasonal slow slip on the Main Himalayan Thrust (MHT) fault driven by hydrological loading related to the monsoon and driving seasonal variations of seismicity. While we find the analysis interesting, we spell out some reasons why the claim should be considered with caution. [...] Numéro de notice : A2020-826 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1038/s41467-020-15100-7 Date de publication en ligne : 13/03/2020 En ligne : https://doi.org/10.1038/s41467-020-15100-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96831
in Nature communications > vol 11 (2020) . - n° 1375[article]
