Article

Facturación a distintas escalas y campos de esfuerzos durante la tectogenesis alpina en el área de Mosqueruela (Teruel)

Estudios Geológicos (Impact Factor: 1.05). 01/1994; DOI: 10.3989/egeol.94501-2307
Source: DOAJ

ABSTRACT The analysis of the brittle tectonic deformation on all scales in one area of the eastern Iberian Chain (Mosqueruela, Teruel) allows us to define a fracture pattern characterized by three main sets: NNE to NE, ENE and E to ESE. Brittle structures (stylolites, tension gashes, brittle-ductile shear zones and faults) show a poliphase Alpine tectonics. From the analysis of fault populations two compressive (wrench regime) phases and a multidirectional extension regime have been inferred. Their chronological evolution is the fol1owing: 1) ENE compression; 2) ESE compression; 3) nearly multidirectional NNE extension. The study of fractures using a number of methodologies at macro-, meso- and microstructural scales allows us to suggest a model of stress distribution and relationships between different structures in sorne areas. The detailed fracture mapping on a hectometric scale shows the distribution and strike variations of fractures. These changes have been interpreted as stress deflection phenomena due to major structures which, in many cases, were identified. Examples of stress deflections have been analyzed both for strike-slip and normal fault sets.

El análisis de la deformación tectónica frágil a distintas escalas en un sector de la Cordillera Ibérica oriental ha permitido definir el patrón de fracturación, caracterizado por tres familias principales de fracturas (NNE a NE, ENE YE a ESE). Las estructuras frágiles (estilolitos, juntas de extensión, zonas de cizalla semifrágil y, fundamentalmente, fallas) registran una tectónica alpina polifásica. Del análisis poblacional de las microfal1as se infieren dos campos de esfuerzos compresivos, principalmente en régimen de desgarre, de los cuales sólo el primero tiene reflejo a nivel macroestructural, y un estado distensivo en régimen de extensión radial o multidireccional. Las relaciones de corte observadas entre las ditintas estructuras ha mostrado la evolución temporal siguiente: 1) compresión ENE; 2) compresión ESE y 3) distensión NNE tendente a radial. El estudio de la fracturación mediante distintas metodologías adaptadas a la escala macro, meso y microestructural ha permitido establecer nexos de relación entre los resultados de todas ellas y poner de relieve la influencia que las estructuras mayores tienen en aquellas de menor rango. Así, la cartografía detallada de fracturas (fundamentalmente a escala mesoestructural) ha permitido observar variaciones en la distribución y orientación de las mismas. Tales variaciones han sido interpretadas como fenómenos de perturbación de esfuerzos por estructuras mayores que, en la mayoría de los casos, han podido ser identificadas. Se han estudiado ejemplos de estas perturbaciones en relación con familias de fallas tanto de desgarre como de componente normal.

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Available from: Carlos L. Liesa, Mar 11, 2014
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