Correlation analysis between the subsides reported as sinkholes and the thickness of the clays of the shallow aquifer in Mexico City (CDMX).

CDMX is the capital of the country. This town has historically been at risk of subsidence damage to its civil structures due to its foundation. The area began to be populated with settlements in flooded areas for use in crops, followed by the colonization and subsequent drying out of the lake areas that ended up being urbanized. The areas formerly belonging to Lake Texcoco, previously used for cultivation, were drained to expand the developable coverage. As the water demand grew, it became necessary to extract groundwater from the shallow aquifer to supply the growing city. Although the depletion of this aquifer coincides with subsidence areas, previous studies indicate that there is no linear correlation between them. The objective of this project is to collect the different criteria related to the presence of sinkholes (as an effect of subsidence), such as Population and well density, distance to faults, fractures, roads, drainage, elevation and slope of the terrain, the thickness of subsoil clays, the type of rock and soil, the rate of subsidence and the geotechnical zones in the study area.

The criteria maps were compared with previous sinkholes mapping registered between the years 2017 to 2019. The statistics consisted of calculating the percentage of coincidence in coverage, categorized linear regression, and the application of logarithms as a normalization method to evaluate its correlation. The statistics consisted of calculating the percentage of coincidence in coverage, categorized linear regression, and the application of logarithms as a normalization method to evaluate its correlation. The most relevant results include the relationship between the sinkholes and the road zones (60%), the highest correlation registered in clays is 0.437 considering areas of competent rock. Although considering the total study site a 0.36 is reached, obtained from applying the logarithm of the clay values ​​and correlating it with the sinkhole areas.

 

• ¹Facultad de Ingeniería, Colegio de Geofísica, BUAP, Puebla, Mexico
• ²Laboratorio de Percepción Remota, Departamento de Recursos Naturales, Instituto de Geofísica, UNAM, CDMX, México
• ³Departamento de Recursos Naturales, Instituto de Geofísica, UNAM, CDMX, México
• ⁴Facultad de Ingeniería Civil, Universidad Nacional Autónoma de México, CDMX, México
• ⁵Consejo Nacional de Ciencia y Tecnología, Cátedras CONACYT- Instituto de Geofísica, UNAM, CDMX, México
• ⁶Facultad de Ingeniería, UNAM, CDMX, México
• ⁷Instituto de Geofísica, UNAM, CDMX, México