## 3 Methods and Materials  
For the analysis of the degree of temporal deformation of the surfaces in the study region, and as this deformation may be related to the regional tectonic activity, a correlation is sought between the temporal analysis involving data obtained using the Synthetic Aperture Differential Interferometry (DInSAR) technique and the factors that influence this ground deformation due to the kinematics associated with the effect generated by the Seismic Nest of Bucaramanga and the Bucaramanga Fault. To this end, based on the workflow described in Figure 2, this relationship is sought to establish points of convergence that give an idea of the terrain's pattern of behavior. The use of DInSAR data can be a very versatile tool in the study of ground deformation conditions, as it provides the opportunity to generate an analysis regionally, with advanced satellite techniques, low costs, and a shorter data processing time [23; 41]. Figure 1: Study area for the evaluation of surface deformation (red polygon). The yellow and orange dates describe the scenes and the direction of acquisition of the images belonging to the Copernicus Sentinel-1 program. Figure 2: Workflow of the study of ground deformation through the analysis of DInSAR data and its correlation with regional tectonic activity. SBAS: Small Baseline Subset. To establish the relationship between these conditions following the designed workflow (Figure 2), the first and second steps are carried out via the Alaska Satellite Facility portal [42], in which satellite images taken over the study region are delimited, filtered, processed, and downloaded. Within these first two steps is framed the pre-processing of the satellite images provided on the ASF portal, which are part of the European Space Agency's (ESA's) Copernicus program and its Sentinel-1 mission, which takes images of C-band synthetic aperture radar [43]. The selection of the images is performed by means of the classification of specific parameters based on creating a phase difference between multi-temporal pairs of Synthetic Aperture Radar (SAR) images of the same study area. This allows precision monitoring of regions that present deformations or displacements in the ground surfaces that are observed based on the record generated by the satellite's Line-of-Sight (LOS) displacement image [1]. Within the configuration parameters (filters) in the ASF portal, the selection polygon for the Sentinel-1 images is created, the date range is established (which for the present study is carried out in multi-temporal mode between the years 2014 and 2021), the type of image format is selected to generate the differential interferometry, Single Look Complex (L-1 SLC), Imaging Mode, Interferometric Wide Swath (IW), Polarization (Dual HH + HV, VV + VH and Single HH, VV) and Satellite Path Direction (Ascending and Descending), both of which are independently processed paths. With the classification parameters established, a relationship between SAR images is then sought to generate a chronologically ordered pair (master and slave image), basically defined as the baseline selection for the two images. This was done in order to create differential interferometry from the selection of images by means of the Small Baseline Subset (SBAS) technique, taking advantage of the characteristics of SAR images for a short temporal and special baseline [2; 44]. With the creation of the baseline and the selection of the ordered pair of images, the processing of these elements is carried out to obtain differential interferometry. This processing is performed using the Alaska Satellite Facility's Hybrid Pluggable Processing Pipeline (ASF HyP3) program, which is a tool available on the ASF portal [45; 46].