TAZ-TFG-2020-1711


Minerales de la arcilla como potenciales archivos de cambios climáticos en las sucesiones costeras del Jurásico Superior de Galve (Teruel)

Rodrigo Molina, Irene
Bauluz Lázaro, Blanca (dir.) ; Bádenas Lago, Beatriz (dir.)

Universidad de Zaragoza, CIEN, 2020
Departamento de Ciencias de la Tierra,

Graduado en Geología

Resumen: The Upper Jurassic (uppermost Kimmeridgian to lowermost Tithonian) Cedrillas Formation in the Galve subbasin (Teruel) represents deposition in coastal environments and consists on four sequences defined the relative dominance of carbonate, mixed and siliciclastic facies (Val et al., 2018; Val, 2020). This relative dominance of carbonate-siliciclastic deposition has a climatic control (arid to humid periods). This work focuses on the application of clays minerals as paleoclimate proxy in the Cedrillas Formation, in particular, evaluate the proposed climatic control on the unit by means of the clay mineralogy.
A detailed mineralogical analysis of 20 selected muddy samples (grey marls, red mudstones) representing coastal plain to marginal lagoon sediments of the Cedrillas Formation, has been carried. The mineralogy was determined both in whole samples and their corresponding less than 2 µm fractions using X-ray diffraction. From these data, the arid/wet index have been calculated (illite+chlorite vs kaolinite+smectite).
The principal minerals present are quartz, calcite and clay minerals, also feldspars and dolomite are found in smaller proportions, and siderite and hematites as accessories .
Main clay minerals are illite, kaolinite, chlorite, sepiolite, paligorskite and some smectite. The study suggests that most of the clays of the Cedrillas Formation are probably detrital, whereas the fibrous clays (sepiolite and paligorskite) might be both authigenic and detrital.
The combination of the mineralogical analysis and the knowledge of the sedimentological and stratigraphy context of the unit makes possible to confirm that the proposed carbonate-siliciclastic cycles where in turn with arid (dominated by illite and chlorite)-humid conditions (dominated by kaolinite and smectite), respectively. Furthermore, clay minerals also indicate that the inprint of the extensive tectonics coeval with sedimentation at the upper part of the unit, did not obliterate the climate signal. In addition, the clay mineralogy suggest that the humid cycles would correspond to warm and humid conditions.
Therefore, the clay mineralogy is a good and powerful paleoclimatic proxy in transitional environments if the clays has not been modified by diagenesis.


Tipo de Trabajo Académico: Trabajo Fin de Grado

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El registro pertenece a las siguientes colecciones:
Trabajos académicos > Trabajos Académicos por Centro > Facultad de Ciencias
Trabajos académicos > Trabajos fin de grado



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