Application of high resolution geophysical prospecting to assess the risk related to subsurface deformationin Mexico City
Por:
Centeno-Salas F.A., Carreón-Freyre D., Flores-García W.A., Gutiérrez-Calderón R.I., Luna-Sánchez E.
Publicada:
1 ene 2015
Resumen:
In the eastern sector of Mexico City the sub soil consists of high
contrasting sequences (lacustrine and volcanic inter bedded deposits)
that favor the development of erratic fracturing in the surface causing
damage to the urban infrastructure. The high-resolution geophysical
prospecting are useful tools for the assessment of ground deformation
and fracturing associated with land subsidence phenomena.
The GPR method allowed to evaluate the fracture propagation and
deformation of vulcano-sedimentary sequences at different depths, the
main electrical parameters are directly related with the gravimetric and
volumetric water content and therefore with the plasticity of the near
surface prospected sequences. The active seismology prospection
consisted in a combination of Seismic Refraction (SR) and Multichannel
Analysis of Surface Waves (MASW) for the estimation of the velocity of
the mechanical compressive (P) and the shear (S) waves. The integration
of both methods allowed to estimate the geomechanical parameters
characterizing the studied sequence, the Poisson Ratio and the
volumetric compressibility.
The obtained mechanical parameters were correlated with laboratory
measured parameters such as plasticity index, density, shear strength
and compressibility and, GPR and seismic profiles were correlated with
the mapped fracture systems in the study area. Once calibrated, the
profiles allowed to identify the lithological contact between lacustrine
and volcanic sequences, their variations of thicknesses in depth and to
assess the deformation area in the surface. An accurate determination of
the geometry of fracturing was of the most importance for the assessment
of the geological risk in the study area.
Filiaciones:
Centeno-Salas F.A.:
Posgrado en Ciencias de la Tierra, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico
Centro de Evaluación de Riesgo Geológico (CERG), Delegación Iztapalapa Del Distrito Federal, Mexico
Carreón-Freyre D.:
Laboratorio de Mecánica Geosistemas (LAMG), Centro de Geociencias, UNAM, Querétaro, Mexico
Flores-García W.A.:
Centro de Evaluación de Riesgo Geológico (CERG), Delegación Iztapalapa Del Distrito Federal, Mexico
Gutiérrez-Calderón R.I.:
Centro de Evaluación de Riesgo Geológico (CERG), Delegación Iztapalapa Del Distrito Federal, Mexico
Luna-Sánchez E.:
Posgrado en Ciencias de la Tierra, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico
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