## 7 Discussion and Conclusions  
The classification and analysis of the studied deformation structures by means of geological structural analysis provide an overall view of the structural arrangement of damage across the entire archaeological site. The study comprehends a total of 163 structural measurements on the orientation and direction (when possible) of deformation structures, pointing to a consistent N145\({}^{\circ}\)-150\({}^{\circ}\) E average orientation of damage (Figure 19). This result has been obtained from the analysis of eleven different types of deformation structures catalogued as \"Earthquake Archaeological Effects\" (EAEs) [(41; 45)], and worldwide recognized as indicators of ancient earthquakes, e.g., [(40; 48; 50; 53; 55; 58; 59; 60)]. Figure 18: Dipping broken corners in the base of columns in the Abderraman III Saloon; (**A**) Close up view of a dipping broken corner in the base of a column and density and rose diagram of the poles of the fractures; (**B**) Map of the Abderraman III Saloon and Attached Rooms (red lines is the horizontal projection of the dipping broken corners poles). Some of the analyzed EAEs are supbarallel to the overall ground slope of the site (Figure 19) so they could be attributed to directional collapses by slope process before or during the earlier burial stages of the abandoned city (i.e., some tilted and wall collapses; Figures 11 and 19). Other EAEs can only be related to building-oriented damage (BOD) of seismic origin. This is the case of dropped or displaced keystones (Figures 6-8), rotation of structural elements (Figure 10), conjugated fractures in pavements (Figures 14 and 15), folded pavements (Figures 16 and 17), impact marks in clean pavements (Figure 9) and dipping broken corners in the base of columns in the Abderraman III Saloon (Figure 18). Some of the modern archaeological excavations indicate that the site was early buried after its abandonment. In the houses attached to the mosque (sector 10 in Figure 4) there are collapsed walls and roofs that directly impacted on the old pavement, with piles of ceiling tiles oriented in a NW-SE direction coming from the south, i.e., counter-slope collapses [37]. This author indicates that this destruction horizon contains dark clayey levels with animal bones and pottery fragments of a clear caliphal chronology (\(\leq\)1009 CE) which was rapidly buried by a thick pile of debris-slope deposits incorporating many elements, blocks and pottery fragments of the ruined city. These upper debris levels contain Hispano-Muslin rounded pottery fragments of post-caliphal age, sandy levels as well as rubble and stucco horizons from the medieval plundering of the ruins [37]. This fragmentary information from punctual modern excavations does not demonstrate the seismic nature of the studied deformations, but reinforces the hypothesis on their seismic origin suggested by the analysis of oriented damage developed in this paper. That is, the homogeneous direction of ground motion deduced from the performed analysis  
Figure 19: Map of the Caliphal City of Medina Azahara showing the average trajectories of maximum horizontal strain (yellow dashed lines) obtained from the geological structural analysis of EAEs. Number codes refer to surveyed sites referenced in Figure 4 (Section 5). The urban map of the archaeological site is showed on the Digital Terrain Model (2 m/pixel) obtained from Lidar data of the PNOA database (IGN): [[https://pnoa.ign.es/el-proyecto-pnoa-lidar](https://pnoa.ign.es/el-proyecto-pnoa-lidar)]([https://pnoa.ign.es/el-proyecto-pnoa-lidar](https://pnoa.ign.es/el-proyecto-pnoa-lidar)) (accessed on 20 February 2022). (Figure 19) indicates that the oriented damage recorded in Medina Azahara can be certainly related with a damaging earthquake (\(\geq\)VII MSK) that contributed to the destruction and ruin of the city.