This research presents the results for analyses done to five geopotential global models(GGM),comparing them with ground data from GNSS and leveling in heterogenic zones from the geodetic perspective,in Chile and Spain...This research presents the results for analyses done to five geopotential global models(GGM),comparing them with ground data from GNSS and leveling in heterogenic zones from the geodetic perspective,in Chile and Spain.While the official and complete implementation of the International Height Reference Frame(IHRF)has not yet been established,the vertical geodetic system of many countries is not calculated on a global scale;instead,it is calculated by the variation of relative heights between one or more local tide gauges,such as in the case of Spain and Chile.This aspect creates regional and specific altimetry data,which disables the use of GGM to directly obtain the orthometric height of the vertical reference system(VRS)from the GNSS heights.Global models currently reach centimetric precision due to their high resolution but are directly incompatible for a local level.To solve this,we expose in this article the contrast between geometric geoidal undulation(ellipsoidal heights and orthometric data from the leveling networks in Spain and Chile)with the geoidal undulation in more recent models and higher resolution:Earth Gravitational Model 2008(EGM08),European Improved Gravity model of the Earth by New techniques(EIGEN6 C4),Gravity Observation Combination(GOCO05 C),Experimental Gravity Field Model(XGM2016),and Ultra-High Resolution Global Geopotential Model(SGG-UGM),adjusting the residual between both referential heights by different parametric models and polynomials of determined order.Once evaluated,their geoidal undulations are combined with GNSS/leveling data from the corresponding VRS to generate a correcting surface,which is also known as a hybrid geoid,resulting in a model of optimal adjustment for the combination of five parameters of the EIGEN-6 C4 with orthometric heights and ellipsoids of both Chile and Spain.The results show 2-3 cm precisions,which were statistically analyzed to determine the suitability for use.The final products are three grids of independent hybrid geoids,one for northern Spain and two for Chile(central and north),which allow continuous access to the VRS of each country using the GNSS’s full potential until the IHRF is available and ready for use.展开更多
This article investigates crustal displacements in Chile between 2019 and 2022,a region marked by the interaction between three Plates.Utilizing the Red Geod esica para la Minería(Geodetic Network for Mining,REDG...This article investigates crustal displacements in Chile between 2019 and 2022,a region marked by the interaction between three Plates.Utilizing the Red Geod esica para la Minería(Geodetic Network for Mining,REDGEOMIN),which incorporates GNSS stations within Chile and fiduciary stations from the International GNSS Service(IGS)and the Sistema de Referencia Geod esico para las Am ericas(Geodetic Reference System for the Americas,SIRGAS)outside the country,our solutions are aligned with the International Terrestrial Reference Frame(ITRF).This approach ensures our research has significant local relevance and contributes to the global scientific community.This work thoroughly analyses GNSS geodetic infrastructure and covers equipment specifications,post-processing data availability,and quality control measures.REDGEOMIN's methodology aligns with IGb14 and the SIRGAS-Continuously Operating Network(SIRGAS-CON),ensuring precision and reliability.The primary objective of this research is to identify regions with significant displacement and areas requiring densification to improve vector variation.The study achieved high precision in aligning station coordinates to the IGb14 frame,with deviations of less than 1 mm,and to SIRGAS-CON,with deviations of 1 mm in planimetry and 2 mm in altimetry.The temporal evolution from 2019 to 2022,analyzed through the Analysis Deformation Beyond Los Andes(ADELA)project,reveals 3—5 cm/year displacements during interseismic periods,with contrasting directions in the northern and south-central regions.Metric displacements during co-seismic periods underscore the compelling necessity for kinematic reference frames in Chile and the incorporation of co-seismic displacement into scientific processing software.Therefore,this study ultimately emphasizes the need to establish a robust geodetic infrastructure in Chile,aiming for a comprehensive characterization and monitoring of the existing geodynamic processes in this region.These results,with their significant practical applications for future geodetic research and mining in Chile and internationally,enhance the precision and safety of mining operations in seismic zones,thereby demonstrating the relevance and applicability of the findings.展开更多
基金financial support for the Chilean part of the project from the Scientific and Technological Research Department of USACH(DICYT in Spanish)through the project DICYT-Regular 091612TM。
文摘This research presents the results for analyses done to five geopotential global models(GGM),comparing them with ground data from GNSS and leveling in heterogenic zones from the geodetic perspective,in Chile and Spain.While the official and complete implementation of the International Height Reference Frame(IHRF)has not yet been established,the vertical geodetic system of many countries is not calculated on a global scale;instead,it is calculated by the variation of relative heights between one or more local tide gauges,such as in the case of Spain and Chile.This aspect creates regional and specific altimetry data,which disables the use of GGM to directly obtain the orthometric height of the vertical reference system(VRS)from the GNSS heights.Global models currently reach centimetric precision due to their high resolution but are directly incompatible for a local level.To solve this,we expose in this article the contrast between geometric geoidal undulation(ellipsoidal heights and orthometric data from the leveling networks in Spain and Chile)with the geoidal undulation in more recent models and higher resolution:Earth Gravitational Model 2008(EGM08),European Improved Gravity model of the Earth by New techniques(EIGEN6 C4),Gravity Observation Combination(GOCO05 C),Experimental Gravity Field Model(XGM2016),and Ultra-High Resolution Global Geopotential Model(SGG-UGM),adjusting the residual between both referential heights by different parametric models and polynomials of determined order.Once evaluated,their geoidal undulations are combined with GNSS/leveling data from the corresponding VRS to generate a correcting surface,which is also known as a hybrid geoid,resulting in a model of optimal adjustment for the combination of five parameters of the EIGEN-6 C4 with orthometric heights and ellipsoids of both Chile and Spain.The results show 2-3 cm precisions,which were statistically analyzed to determine the suitability for use.The final products are three grids of independent hybrid geoids,one for northern Spain and two for Chile(central and north),which allow continuous access to the VRS of each country using the GNSS’s full potential until the IHRF is available and ready for use.
基金This research has been funded according to:Tender ID:1562-44-LQ19 and ANID ID23I10147.
文摘This article investigates crustal displacements in Chile between 2019 and 2022,a region marked by the interaction between three Plates.Utilizing the Red Geod esica para la Minería(Geodetic Network for Mining,REDGEOMIN),which incorporates GNSS stations within Chile and fiduciary stations from the International GNSS Service(IGS)and the Sistema de Referencia Geod esico para las Am ericas(Geodetic Reference System for the Americas,SIRGAS)outside the country,our solutions are aligned with the International Terrestrial Reference Frame(ITRF).This approach ensures our research has significant local relevance and contributes to the global scientific community.This work thoroughly analyses GNSS geodetic infrastructure and covers equipment specifications,post-processing data availability,and quality control measures.REDGEOMIN's methodology aligns with IGb14 and the SIRGAS-Continuously Operating Network(SIRGAS-CON),ensuring precision and reliability.The primary objective of this research is to identify regions with significant displacement and areas requiring densification to improve vector variation.The study achieved high precision in aligning station coordinates to the IGb14 frame,with deviations of less than 1 mm,and to SIRGAS-CON,with deviations of 1 mm in planimetry and 2 mm in altimetry.The temporal evolution from 2019 to 2022,analyzed through the Analysis Deformation Beyond Los Andes(ADELA)project,reveals 3—5 cm/year displacements during interseismic periods,with contrasting directions in the northern and south-central regions.Metric displacements during co-seismic periods underscore the compelling necessity for kinematic reference frames in Chile and the incorporation of co-seismic displacement into scientific processing software.Therefore,this study ultimately emphasizes the need to establish a robust geodetic infrastructure in Chile,aiming for a comprehensive characterization and monitoring of the existing geodynamic processes in this region.These results,with their significant practical applications for future geodetic research and mining in Chile and internationally,enhance the precision and safety of mining operations in seismic zones,thereby demonstrating the relevance and applicability of the findings.
