Site effects in Mexico City urban zone. A complementary study

Debido a la sencillez de su registro y a la facilidad relativa de su análisis, los microtremores se han convertido en una herramienta de gran utilidad para los estudios de microzonificación sísmica. El método SPAC propuesto por Aki (1957) permite obtener información sobre la estratigrafía del sitio en estudio, a partir de registros de microtremores obtenidos con un arreglo instrumental. El efecto de sitio, caracterizado por el periodo dominante y la amplificación, se estima con la estratigrafía obtenida. En este artículo se presentan las generalidades del método SPAC, su aplicación a registros de un arreglo instrumental en Ciudad Universitaria, México, y se realiza una comparación con los resultados obtenidos con el método de F-K por Kagawa (1996). La estructura de velocidades obtenida en este trabajo es consistente con la obtenida por Kagawa (1996). También se concluye que el método SPAC es más eficiente que el método F-K, pues requiere menor número de arreglos y menor número de estaciones por arreglo para obtener los mismos resultados. También se presenta la función de transferencia del modelo de velocidades obtenido, y se compara con la función de transferencia del modelo de velocidades de Kagawa, y también con la obtenida con cocientes espectrales de datos de terremotos. Este ejemplo muestra que a partir de registros de microtremores y el método SPAC es posible realizar una estimación confiable de la estructura de velocidades.

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Site effects in Mexico City eight years after the September 1985 Michoacan earthquakes

Soil Dynamics and Earthquake Engineering ◽

10.1016/0267-7261(94)90028-0 ◽

1994 ◽

Vol 13 (4) ◽

pp. 229-247 ◽

Cited By ~ 70

Author(s):

Francisco J. Chávez-García ◽

Pierre-Yves Bard

Keyword(s):

Mexico City ◽

Site Effects

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Site effects in Mexico City: Constraints from surface wave inversion of shallow refraction data

Journal of Applied Geophysics ◽

10.1016/s0926-9851(96)00057-2 ◽

1997 ◽

Vol 36 (4) ◽

pp. 157-165 ◽

Cited By ~ 7

Author(s):

J. Ramos-Martínez ◽

F.J. Chávez-García ◽

E. Romero-Jiménez ◽

J.L. Rodríguez-Zúñiga ◽

J.M. Gómez-González

Keyword(s):

Surface Wave ◽

Mexico City ◽

Site Effects ◽

Wave Inversion ◽

Refraction Data

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Evaluation of ecological quality in peri-urban rivers in Mexico City: a proposal for identifying and validating reference sites using benthic macroinvertebrates as indicators

Journal of Limnology ◽

10.4081/jlimnol.2015.1304 ◽

2015 ◽

Cited By ~ 2

Author(s):

Angela Caro-Borrero ◽

Javier Carmona Jiménez ◽

Marisa Mazari Hiriart

Keyword(s):

Mexico City ◽

Human Activity ◽

Latin American ◽

Ecological Quality ◽

Urban Rivers ◽

Reference Sites ◽

Discharge Flow ◽

Urban Zone ◽

Good State

Conservation and management of aquatic ecosystems that are significantly influenced by urban activities requires the classification and establishment of potential reference sites. However, in Latin American countries, policies are not available that outlines the identification and evaluation of such sites. Therefore, this study represents a proposal for evaluating the ecological quality of peri-urban rivers in the conservation soil (CS) areas/zones of Mexico City. The proposal accounts for the zone’s physicochemical, hydromorphological, and bacteriological characteristics along with its macroinvertebrate richness. Our evaluation was performed using a canonical correspondence analysis (CCA) and indicator values (IndVal) calculated for different species. River headwaters serve/work as a good physicochemical point for potential references sites. However, the hydromorphology of the CS has been gradually modified by numerous hydraulic alterations within the peri-urban zone. Using the CCA and IndVal, two types of sites were confirmed: sites in a good state of conservation and quality and sites modified by human activity, featuring lower discharge flow, poor quality hydromorphological values and Oligochaeta class organisms. At the sites featuring a good state of conservation and quality, higher hydromorphological values were positively correlated with discharge flow and certain macroinvertebrate taxa, including Nemouridae, Podonominae, Tanypodinae, Acarina, Baetis, Tipula, Antocha, Atopsyche, Glossosoma, Polycentropus, Hesperophylax and Limnephilus. In the sites modified by human activity, the genus Simulium was classified as a disturbance-tolerant organism. The river reach within the urban zone is basically an open-air drainage ditch. Evaluations of the ecological quality of the riparian zone were used to identify the most important hydromorphological qualities and discharge flow parameters and to select the most appropriate factors that should be monitored in peri-urban rivers of the Mexico Basin.

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