Centre de documentation
scientifique

A continuous velocity field for Norway / Halfdan Pascal Kierulf in Journal of geodesy, vol 87 n° 4 (April 2013)  

Public [article]  inJournal of geodesy > vol 87 n° 4 (April 2013) . - pp 337 - 349 Titre : A continuous velocity field for Norway Type de document : Article/Communication Auteurs : Halfdan Pascal Kierulf, Auteur ; Mohammed Ouassou, Auteur ; Matthew Simpson, Auteur ; Olav Vestol, Auteur Année de publication : 2013 Article en page(s) : pp 337 - 349 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale [Termes IGN] champ de vitesse [Termes IGN] krigeage [Termes IGN] Norvège [Termes IGN] positionnement par GNSS [Termes IGN] quantité continue Résumé : (Auteur) In Norway, as in the rest of Fennoscandia, the process of Glacial Isostatic Adjustment causes ongoing crustal deformation. The vertical and horizontal movements of the Earth can be measured to a high degree of precision using GNSS. The Norwegian GNSS network has gradually been established since the early 1990s and today contains approximately 140 stations. The stations are established both for navigation purposes and for studies of geophysical processes. Only a few of these stations have been analyzed previously. We present new velocity estimates for the Norwegian GNSS network using the processing package GAMIT. We examine the relation between time-series length and precision. With approximately 3.5 years of data, we are able to reproduce the secular vertical rate with a precision of 0.5 mm/year. To establish a continuous crustal velocity field in areas where we have no GNSS receivers or the observation period is too short to obtain reliable results, either interpolation or modeling is required. We experiment with both approaches in this analysis by using (i) a statistical interpolation method called Kriging and (ii) a GIA forward model. In addition, we examine how our vertical velocity field solution is affected by the inclusion of data from repeated leveling. Results from our geophysical model give better estimates on the edge of the network, but inside the network the statistical interpolation method performs better. In general, we find that if we have less than 3.5 years of data for a GNSS station, the interpolated value is better than the velocity estimate based on a single time-series. Numéro de notice : A2013-217 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-012-0603-2 Date de publication en ligne : 09/11/2012 En ligne : https://doi.org/10.1007/s00190-012-0603-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32355 [article]

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
266-2013041	SL	Revue	Centre de documentation	Revues en salle	Disponible

The kinematics of Ny-Ålesund from space geodetic data / Halfdan Pascal Kierulf in Journal of geodynamics, vol 48 n° 1 (July 2009)  

Public [article]  inJournal of geodynamics > vol 48 n° 1 (July 2009) . - pp 37 - 46 Titre : The kinematics of Ny-Ålesund from space geodetic data Type de document : Article/Communication Auteurs : Halfdan Pascal Kierulf, Auteur ; Bjørn Ragnvald Pettersen, Auteur ; Daniel S. MacMillan, Auteur ; Pascal Willis , Auteur Année de publication : 2009 Article en page(s) : pp 37 - 46 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux [Termes IGN] marégraphe [Termes IGN] positionnement par DORIS [Termes IGN] positionnement par GPS [Termes IGN] positionnement par ITGB [Termes IGN] repère de référence [Termes IGN] Spitzberg [Termes IGN] station permanente Résumé : (auteur) We have compared coordinate time series from several space geodetic observing techniques to derive the kinematical motions of Ny-Ålesund, Svalbard. Velocity estimates from VLBI, GPS, and DORIS scatter more than the expected error estimates from each technique, and also between individual GPS solutions with different software and analysis strategies. A statistical combination yields average topocentric velocity components of mm/year (north), mm/year (east), and mm/year (vertical) for 1993–2007. The horizontal velocity is in agreement with a combined prediction of NUVEL-NNR-1A and the effects of post-glacial rebound and present day ice melt of nearby glaciers. The observed uplift is twice that predicted by the two latter processes. The non-linear time series of both VLBI and GPS data suggest that the uplift rate increases from 7.0 mm/year before 2003 to 10.8 mm/year after 2003. We conclude that this has a geophysical origin since no monument motions have been detected. A recent sea level decrease (1993–2007) of mm/year supports an absolute sea level increase of 3.2 mm/year as determined elsewhere by satellite altimetry. Numéro de notice : A2009-550 Affiliation des auteurs : IGN+Ext (1940-2011) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.jog.2009.05.002 Date de publication en ligne : 14/05/2009 En ligne : https://doi.org/10.1016/j.jog.2009.05.002 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89890 [article]