E-Prints Complutense

Abstract

Spain is the most self-sufficient country for minerals in the EsU. A major proportion of these Spanish mineral resources has been oblained from Tertiary material-. The main material exploited in Tertiary basins have been: brown coal and lignites, potassium salts, sodium salts (sulphates and chlorides), diátomite, sepiolite and other absorbent days, bentonites, celestine. pumíce and also dimension (building) stones and ceramícs, portland cement and plaster raw materials. Pb-Zn-Ag and gold alunite volcanogenic ores, related to Neogene volcanism, besides Au-placers have been mined from Roman times, Minor Cu and Mn occurrences are also reviewed. The brown coal mines of Galician basins have provided all the sígnificant productíon of Spain: more than 17 Mt. Low-quaility Oligocene lignites in the eastern part of the Ebro Basin and Balearic Islands are less important from tbe economic point of view. Other occurrences are in the Guinzo de Limia. Guadix Baza. Granada (Arenas del Rey) and Alcoy basins. The Spanish Tertiary basins (continental and marine, (Oligocene-Miocene) are filled by thick evaporites in which are obtained potassium salts and sodium salts (sulphates and chlorides). The Montevives celestine mine is located in the evaporitic unit of the Granada basin (Miocene), and provides all of the Spanish celestine production. Spain is the world's third largest producer of celestine. The Madríd basin and the minor Calatayud basín supply the whole of Spanish sepiolitic production. The most important Spanish attapulgite production is obtained from the El Cuervo mine (Sevilla and Cádiz provinces). The genesis of the Cabo de Gata bentonite deposits is thought to be by hydrothermal alteration and halmyrolsis of Neogene volcanic roch. The Madrid basin bentonites and 'pink days' have been interpreted as an early diagenetic. even edaphic Mg-rich, attapulgitization of illite clays. The most important areas of ceramic c1ay production in Spain are localed in the Guadalquivir basin (Bailen area) and the Madrid basin, (La Sagra Alcalá de Henares). The continental Neogene basin ofthe Hellin area supplies 90 % of Spanish diamote production.