Resumen de Una forma de metamorfismo térmico: incendios de minas de carbón
José Antonio Sáenz de Santa María Benedet, Ana María Gutiérrez Rodríguez, Covadonga Brime Laca, Marcos Castro Rivas
Combustion of a coal seam in La Meruxal zone (Carboniferous Coal Basin, Cantabrian Zone) has produced an intense thermal alteration of the surrounding rocks most evident in the case of the sandstones. This alteration is shown at the outcrop scale by the change in colour o f the rocks that now have a quite intense redish colour, and their tenacity. In thin section sandstone grains are strongly fragmented with grains divided in several fragments separated by a fine grain matrix. Mineralogy has also been change appearing new high temperature phases such as mullite-sillimanite and cordierite absent in the original region and indicating that temperatures reached were of c. 800QC. Therefore the studied material show the imprint of a high temperature event that could be considered a pyrometamorphic type o f metamorphism.
