Science Service System

Summary of Proposal GEO1521

TitleModeling of surface deformation by DInSAR technique in the active volcanic Deception Island (Antarctica) and comparative analysis with existing models GNSS-GPS.
Investigator Barbero Guerrero, Ignacio - University of Cadiz, mathematics
Team Member
laboratory astronomy Berrocoso Dominguez, Manuel - University of Cadiz, mathematics
SummaryThe application of geodetic GPS global positioning system is based on simultaneous observations of GPS satellites for at least two ground stations. Treatment of these observations provide highly accurate relative positioning between the two stations whose absolute positions are obtained by solving the geodetic network the work stations defined from the relative positioning between the stations making up the network and considering the absolute coordinates of any of them. From this global positioning system control networks can be established for determining the temporal variation of the relative positions between the vertices, whose analysis will provide the model of deformation of the area where the network is established. These new techniques are applied to observations from geodetic networks in different parts of the Earth, which are geo-dynamically active interest from the stand point of volcanology and tectonic. These networks are composed of multiple vertices, which are monitored continuously. From the observations made by the permanent stations obtained time series with sessions of 24h and a follow-up interval of 30sec, we provide 3D​​ deformation models, which provide us with models of horizontal and vertical tectonic deformation of the areas studied. Differential interferometry is based on calculating the phase difference between two SAR images on a same area, so called interferometric phase(interferogram).The phase of the interferogram is related to the difference in distance between a field element and the SAR sensor(usually calibrated in a satellite) between SAR images. So when two become SAR images from slightly different points of view the interference pattern is dominated by differences in distances due to topography. Similarly. When two SAR images are obtained from the same point of view there is no difference in distance dueto the topography in place all the interference pattern would be due to possible displacement of the ground, so we obtain a model of surface deformation in the area to perform the study. In those areas specifically to conduct the study, we found different problems, the morphology of the land due to steep and large areas of the surface coverage of Deception Island when in the south polar region, its surface remains almost year round ice cover, which lies at a great disadvantage in obtaining surface deformation parameter. According to the above, our intention is to correlate the surface deformation models obtained by both techniques in order to obtain a methodology for monitoring the volcano-tectonic active areas. - Methodology: For the model of surface deformation in the area to study by remote sensing technique differential interferometric radar it will apply two different techniques for the treatment of images as they are, Persistent Scatterer (PS) and Small Base Line (SBAS), according to which models will be obtained multitemporal surface deformation for each of the techniques, these models Comparative studies will be conducted to obtain an explanation of the results obtained by assimilating the geodynamic process under study and in order to perform model selection surface as a result of the application of radar interferometry. Parameter for obtaining surface deformation, SAR images which have a hight geometrical precision. It will correlate the results of the models of surface deformation obtained by geodetic techniques, since these models are exempt from this type of disturbance due to having different data sources and methodology in their treatment. It will scan to obtain a correlation of models derived from time series generated by space geodetic techniques and models using remotely sensed radar interferometric technique.

Back to list of proposals

DLR 2004-2016