The NE zone of the Madrid Basin contains palustrine deposits of the Miocene Intermediate Unit which have undergone silicification processes. These processes are conditioned by the type of palustrine deposit within they developed and occur at specific stratigraphic positions in the basin. In this paper we analyze three different sectors. In the Yesares section silícification produced quartz and took place in gypsum deposits which contain bioturbation channels that favoured silica fixation. In the Brihuega area silícification bioturbated palustríne micrites also produce quartz. Both silicifications appear at the top of unit or sequence of the Intermediated Unit. In the Jadraque section the silicification of the micrites and dolomicrites was controlled by the presence of biosiliceous marls and sepiolite. This silicification was consequence of early diagenesis.

Este trabajo se realizó en el marco del proyecto BTE 2002-040 17 -C02-01 del Ministerio de Ciencia y Tecnología en el desarrollo de la beca FPI con referencia BES- 2003-1573.

Peer reviewed