HR: 11:05h
AN: H42B-04 [Abstracts]
TI: Hydrogeophysics and Water Balance of Cerro Prieto Dam, NE Mexico
AU: * Yutsis, V
EM: vyutsis@fct.uanl.mx
AF: Universidad Autónoma de Nuevo León, Facultad de Ciencias de la Tierra, Hda. de
Guadalupe, Carr. a Cerro Prieto, km 8, Linares, NL 67700, Mexico
AU: De León Gómez, H
EM: hdeleon@fct.uanl.mx
AF: Universidad Autónoma de Nuevo León, Facultad de Ciencias de la Tierra, Hda. de
Guadalupe, Carr. a Cerro Prieto, km 8, Linares, NL 67700, Mexico
AU: Masuch Oesterreich, D
EM: gis@fct.uanl.mx
AF: Universidad Autónoma de Nuevo León, Facultad de Ciencias de la Tierra, Hda. de
Guadalupe, Carr. a Cerro Prieto, km 8, Linares, NL 67700, Mexico
AU: Izaguirre, F
AF: Universidad Autónoma de Nuevo León, Facultad de Ciencias de la Tierra, Hda. de
Guadalupe, Carr. a Cerro Prieto, km 8, Linares, NL 67700, Mexico
AB:
The geographical location of the State of Nuevo Leon, due to its physiographic features, has temperate and arid
climate; undeveloped drainage, low precipitations, and high evapotranspiration rates, as well as rapid
demographic growth.
The hydrological data of the Pablillo basin, registered in the hydrometric station Cerro Prieto, showed an annual
precipitation from 415 up to 1130 mm/a , the mean evaporation of 705 mm/a (up to 2460 mm/a in 1996). The
maximum water storage of the Cerro Prieto reservoir is 395 millions m3 which corresponds to a water level of
295 meters. However, this level was reached only three times after the dam's construction. By the end of June
2006 the water level was at 276.2 m which corresponds to a water volume of about 127,806,300 m3 which is less
than a third of maximum storage. Analysis of hydrological data showed sufficient misbalance between water
recharge (by rain, river flow) and loss due to evaporation, filtration, extraction, discharge, etc.
160 gravity reading points, 400 onshore magnetic field readings as well as about 250 offshore magnetic points
were carried out. The standard corrections as instrumental drift, latitude, elevation, IGRF, etc. were applied to
obtained data. Data procession includes Fourier transformation, wavelength filters, upward continuation, vertical
and horizontal derivates, etc. As a result a 2D geological-geophysical models and 3D maps were elaborated.
The general trend of the magnetic field reduced to a pole is NW - SE on which background anomalies of
northeast trend are obviously traced. The general trend of the gravity field received as a result of our works is the
same. However, local magnetic and residual gravity anomalies have mosaic character and, being
morphologically extended in a NE direction, grouped in chains of northwest trend. Potential data interpretation
allows assuming a series of the superficial fractures focused in a NE direction, perpendicular (NW-SE) to the
general deep fault.
The analysis of the received data indicates a sharp variability of volume of fresh water in the basin, due to several
complex factors. Major factors are: hydrogeological and climatic conditions of the region (1), intensive extraction of
fresh water from surrounding areas (urbanization and agricultural activity of the city of Linares), which is reflected
in strong fracturing of the subsurface layers and lowering of aquifer depth (2), presence of a deep fault trending
northwest (3), and a high velocity of recent sedimentation (4).
DE: 0920 Gravity methods (1219)
DE: 1219 Gravity anomalies and Earth structure (0920, 7205, 7240)
DE: 1517 Magnetic anomalies: modeling and interpretation
DE: 1835 Hydrogeophysics
DE: 8010 Fractures and faults
SC: Hydrology [H]
MN: 2007 Joint Assembly