Abstract
back to Publications Geyer, O.F. & Krautter, M. (1998): Die Unterkreide im Grenzgebiet von Aragonien, Neukastilien und Valencia (südwestliches Keltiberikum, Spanien). - Profil 15: 163-239, 25 figs.;Stuttgart.
Die Unterkreide im Grenzgebiet von Aragonien, Neukastilien und Valencia (südwestliches Keltiberikum, Spanien)
Abstract: Chapter 1. - This investigation deals with Early Cretaceous sediments of the Montes Universales and its environs which are in the central part of southwestern Celtiberian Chains (Iberian Chains). The geographic limits of the study area and the scientific situation at the beginning of our investigation are explained. 46 schematic sections are also included (Fig. 4a-d).
Chapter 2. - Due to palaeotectonic reasons, the sediments underlying the Lower Cretaceous in this area are of two different ages. During Early Jurassic, tectonic activities of the "Hesperic Lineament" or "Montes-Universales Fault" led to a block system with different facies on each side of this suture. East of the NW-SE-running lineament, jurassic sedimentation ends during Late Jurassic (Kimmeridgian, developed partly in Purbeck facies; Higueruelas- and Villar de Arzobispo Formation). On the western side of the lineament however, sedimentation ends during late Early Jurassic/early Middle Jurassic (lower part of Chelva Formation).
Chapter 3. - Definitions and different use of the terms "Purbeck" and "Wealden" are discussed. We recommend the use of these terms in a magnafacial sense within this geo-historic time slice and we point out the occurence of "Utrillas-type" sediments within a Wealden Magnafacies (see also Chapter 4.7).
Chapter 4. - The succession of the formations follows earlier investigations performed in the southwestern Celtiberian Range or in the "Serranía de Cuenca" respectively: Collado-/Huérguina Formation, Contreras Formation, Malacara Formation (= Malacara Member of the Caroch Formation in the region of Valencia), Burgal Formation (= Burgal Beds of the Caroch Formation), (Buseo Limestones are not developed in the Montes Universales), Utrillas Formation and Aras de Alpuente Formation (Late Hauterivian?/ Barremian to Late Albian). Collado- and Huérguina Formation are isochrone as they interfinger with each other. These studies proved the existence of thin intercalations of a lacustrine-palustrine Huérguina facies within the fluvial-alluvial Collado Formation. An Early Aptian ("1st cycle" sensu Vilas, Masse & Arias 1993) or early Late Aptian age ("2nd cycle") of the Malacara Formation within the study area is discussed because of the co-occurence of the rudist bivalve Pseudotoucasia together with the foraminifera Palaeorbitolina cormyi.
The palaeogeographic situations of the sedimentary basins (Huérguina Formation, Malacara Formation and Bicuerca Limestones) are reconstructed (Fig. 12, 13, 19). They follow more or less the same NW-SE direction marked by the Hesperic Lineament. The Burgal- and Malacara Formation also occur also much farther to the north than mentioned in former studies.
Chapter 5. - Bedding conditions and the relationship between different formations are highly diverse (Fig. 22). They reveal sedimentary conditions influenced by tectonical and, to a minor degree, sea level changes. The number of superpositions is much bigger than mentioned by N. Melendez (1993). Sedimentary cycles (see Fig. 23) and depositional sequences are published by N. Melendez (1993), Carenas, Garcia, Segura & Peres del Campo (1987) and Garcia et al. (1989) and are largely confirmed with our investigations. Directions of transgressions and the axis of sedimentary basins of diverse formations are more or less parallel to the Hesperic Lineament, although the sedimentary basins shift laterally to a certain degree. The axis of these basins are, as is the Hesperic Lineament, highly stable and show a tight relation to an aulacogenic development, and hence a relation to the "Celtiberian Aulocogene". (Fig. 24, 25).
Chapter 6. - Consists of 46 briefly described sections listed alphabetically (see also Chapter 1, Fig. 4a-d).