Abstract. Sinkhole risks are becoming particularly severe in urban areas that lack careful planning and where karst depressions are frequently filled and developed. Sinkholes frequently have a higher probability of occurrence and a bigger genetic diversity in evaporite rocks than in carbonate rocks. This is because evaporites rocks (halite, gypsum, etc) have a higher solubility. Subsidence damage resulting from this dissolution generates considerable losses at the world. To contract with these risks, is needed the identification, investigation, prediction, and mitigation of sinkholes. Corrective measures might be applied to reduce the subsidence processes. A more practical solution for safe development is to reduce the vulnerability of the structures by using subsidence-proof designs. Therefore, this case study is located in the town of Perdiguera (Zaragoza, Spain), within the Ebro Basin. This town is affected by subsidence problems, which are associated with the dissolution of gypsiferous silts that generate sinking. These sinkholes are affecting the buildings threatening its structural integrity.

Abstract. The ecological risk attached to the filling of Quito’s ravines, together with the subsequent loss of a memory about their existence, are the focus of this paper which aims to provide a base for both comprehension and action. Ravines are part of the geomorphology of the city’s basin and play a vital role in the hydrogeological system of Quito’s water cycle. They have been filled over time, disappearing from urban maps. This disrupts ravines’ original course and natural drainage system generating risks. An integral multi-scale perspective that considers geomorphological and hydrogeological modifications is missing. Three problematics can be observed. Technical-infrastructural, Urban-spatial and Architectural-cultural. The conjugation of all the phenomena described above, constitutes a call to consciously establish the risk level to which this territory is exposed. The damage goes beyond material or human loss. It affects history, living memory, identity, and knowledge. All these aspects have contributed to the consideration of HCQ (Historical Centre of Quito) as World Heritage Site. These are valuable legacies that need to be preserved. Therefore, it is necessary to undertake a detailed inventory of: i) the technical constructive state of patrimonial buildings made using raw earth; ii) the modifications and current state of DMQ’s (Metropolitan District of Quito) ravines; iii) the existing interstitial spaces associated to the ravines’ path within the HCQ. The paradigm under consideration for the future is not conservation but integral protection. Rescuing Memory in relation to HCQ’s ravines as an active operator for transformative provisions associated to social, environmental, urban and architectonic dimensions becomes fundamental for future development.