This research contributes to the understanding of surface deformation in the study area with new knowledge of the upper soil sequence. An established sequence distribution of the shallow layers was set and some of their geotechnical properties were determined. The analized samples are composed by compressible clayey silt and several lenses of volcanic sandy ash. Heterogeneities may be contributing to differential subsidence which is controlling the occurrence of surface faulting.

Ground subsidence has affected Mexico City for over a century, as a result of its large urban expansion and aggressive groundwater extraction rates. The continuous subsidence results in severe damage to urban infrastructure and civil structures. This work is aimed towards a better recognition of subsidence as a major hazard in Mexico, assess the number of inhabitants affected and the spatial extent of the subsiding areas affected by this process.

This paper provides a discussion related to the origin of surface failures in the graben of Aguascalientes. Observations indicate that some of these failures are older than the beginning of pumping, suggesting a natural tectonic origin. Some questions regarding surface failures are formulated, for instance, are the surface failures caused by the combined stresses of pumping and tectonism? Is the current tectonism sufficient to cause some surface or deep failures?