Shearing along faults and stratigraphic joints controlled by land subsidence in the Valley of Queretaro, Mexico
Por:
Carreon-Freyre, D., Cerca, M., Ochoa-Gonzalez, G., Teatini, P., Zuniga, F. R.
Publicada:
1 may 2016
Ahead of Print:
1 ene 2016
Resumen:
Slip of nearly vertical faults or horizontal stratigraphic joints has
provoked the shearing of at least 16 well casings in a period of over 10
years in the Valley of Queretaro aquifer, Mexico. Evidence integrated
from field observations, remote surface-deformation monitoring, in-situ
monitoring, stratigraphic correlation, and numerical modeling indicate
that groundwater depletion and land subsidence induce shearing. Two main
factors conditioning the stress distribution and the location of sheared
well casings have been identified: (1) slip on fault planes, and (2)
slip on stratigraphic joints. Additionally, the distribution of
piezometric gradients may be a factor that enhances shearing. Slip on
faults can be generated either by the compaction of sedimentary units
(passive faulting) or by slip of blocks delimited by pre-existing faults
(reactivation). Major piezometric-level declines and the distribution of
hydraulic gradients can also be associated with slip at stratigraphic
joints. Faults and hydraulic contrasts in the heterogeneous rock
sequence, along with groundwater extraction, influence the distribution
of the gradients and delimit the compartments of groundwater in the
aquifer. Analogue modeling allowed assessment of the distribution of
stress-strain and displacements associated with the increase of the
vertical stress. Fault-bounded aquifers in grabens are common in the
central part of Mexico and the results obtained can be applied to other
subsiding, structurally controlled aquifer systems elsewhere.
Filiaciones:
Carreon-Freyre, D.:
UNAM, Ctr Geociencias, Lab Mecan Geosistemas, 3001 Bvd Juriquilla Col Juriquilla, Queretaro 76230, Mexico
Cerca, M.:
UNAM, Ctr Geociencias, Lab Mecan Geosistemas, 3001 Bvd Juriquilla Col Juriquilla, Queretaro 76230, Mexico
Ochoa-Gonzalez, G.:
UNAM, Ctr Geociencias, Posgrad Ciencias Tierra, 3001 Bvd Juriquilla Col Juriquilla, Queretaro 76230, Mexico
Teatini, P.:
Univ Padua, Dept Civil Environm & Architectural Engn, Padua, Italy
Zuniga, F. R.:
UNAM, Ctr Geociencias, Lab Mecan Geosistemas, 3001 Bvd Juriquilla Col Juriquilla, Queretaro 76230, Mexico
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