Person: Díaz Molina, Margarita
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First Name
Margarita
Last Name
Díaz Molina
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Geológicas
Department
Area
Estratigrafía
Identifiers
4 results
Search Results
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Item Dinosaur nests at the sea shore(Nature -London, 2002) Sanz , J.L.; Moratalla, J.J.; Díaz Molina, Margarita; López Martínez, María Nieves; Kälin, Otto; Vianey-Liaud, M.Item Stream mouth deposits in the palaeontological site of Somosaguas, Middle Miocene, Madrid Basin(Revista española de paleontología, 2012) Díez Canseco, Davinia; López Martínez, María Nieves; Díaz Molina, Margarita; Benito Moreno, María IsabelThe Middle Miocene sediments exposed in Somosaguas contain an excellent record of mammal fossil remains preserved in debris and mudfl ow deposits. In the sedimentary sequence of Somosaguas three facies associations are distinguished, representing alluvial fan and shallow lake margin environments. Alluvial fans are composed of mud and debris fl ow deposits. The whole of the lacustrine deposits are interbedded between debris and mud fl ow deposits. The shallow lake deposits are devoid of fossil remains, and they consist of well-sorted micaceous sandstone bodies with water flow structures, interbedded with thin mudstone beds. These sandstone bodies are interpreted as stream mouth lobes. Three integrated stratigraphic sections show that the lacustrine bedset overlain an erosion surface, probably scoured by flood waters. Palaeocurrent measurements indicate that the sediment filling the shallow lake came from the west and the north.Item Depositional setting and early diagenesis of the dinosaur eggshell-bearing Aren Fm at Bastus, Late Campanian, south-central Pyrenees(Sedimentary geology, 2007) Díaz Molina, Margarita; Kälin, Otto; Benito Moreno, María Isabel; López Martínez, María Nieves; Vicens, EnricThe Late Cretaceous Aren Fm exposed north of Bastus in the Tremp Basin (south-central Pyrenees) preserves an excellent record of dinosaur eggs laid in a marine littoral setting. Different from other cases reported in literature, at the Bastus site the preferential nesting ground was original beach sand. The coastal deposits of Aren Fm can be grouped into four facies assemblages, representing respectively shoreface, beachface, beach ridge plain and backbarrier lagoon environments. Shoreface deposits include fine- to coarsegrained hybrid arenites and subordinate quartz-dominated conglomerates with ripple structures of wave and wave-current origin. Beachface deposits are mainly storm beach conglomerates, but parallel-laminated foreshore arenites locally occur. Backbarrier lagoon deposits comprise of washover sandy conglomerates that grade laterally into sandy lime mudstones, biomicrites and marls. Beach ridge sediment, wherein the bulk of dinosaur eggs and eggshell debris occurs, predominantly is a reddish hybrid arenite that has undergone a complex early diagenetic evolution, including marine and meteoric cementation followed by soil development. The reddish arenites overlie wave-dominated shoreface deposits and in places pass laterally into lagoonal deposits. They originally formed shore ridges, that became stabilized during progradational episodes by pedogenesis (beach ridge, sensu[Otvos, E.G., 2000. Beach ridges—definitions and significance. Geomorphology 32, 83–108.]), which also affected the dinosaur eggs. The eggshell-bearing beach ridge arenites are typically preserved at the top of parasequences forming the systems tracts of a third-order sequence. Thick packages of this facies resulted from aggradation of barrier/beach ridge deposits, whose preservation below surfaces of transgressive erosion was favoured by incipient lithification.Item Up-to-date Spanish continental Neogene synthesis and paleoclimatic interpretation(Revista de la Sociedad Geologica de España, 1993) Calvo Sorando, José Pedro; Daams, Remmert; Morales, J.; López Martínez, María Nieves; Agustí, J.; Anadón, P.; Armenteros, I.; Cabrera, L.; Civis Llovera, Jorge; Corrochano, A.; Díaz Molina, Margarita; Elizaga, E.; Hoyos, M.; Martín-Suárez, E.; Martínez, J.; Moissenet, E.; Muñoz, A.; Pérez-García, A.; Pérez González, Alfredo José; Portero, J.M.; Robles, F.; Santisteban, C.; Torres, T.; Meulen, A.J. van der; Vera, J.A.; Mein, P.A synthesis of the Spanish continental Neogene is presented by designing an integrated correlative chart of the Neo" gen-e "succes"Siuns-ofthe "lberian-PeninsuIa-. -Ninemain-sedimentary-breaks-have-been -distinguished-in-most-of-the "basins. They are considered a valuable criteria for correlation as they occur in similar time intervals from basin to basin. The determined sedimentary breaks occur in the Agenian, Ramblian, Middle Aragonian, Late Aragonian, Late Vallesian, Middle Turolian, Late Turolian, Late Ruscinian-Early Villafranchian, and Villafranchian ages. The larger interior basins (Ebro, Tajo, Duero) show a fairly complete Neogene sedimentary record in which the aboye mentioned sedimentary breaks are usually well recognized. A good correlation may be established from basin to basin. Likewise, there is a fairly good correlation among the Upper Miocene-Pliocene sedimentary record of basins spreading out in Levante and southeastern Spain. However, the correlation is not as c1ear in those basins located within the Iberian and Catalan Coastal Ranges, which usually do not show a similar sedimentary pattern. The comparison between Neogene stratigraphic logs in most of the Spanish continental basins and the pattern of global events from currentIy accepted Cenozoic Cyc1e Charts allows recognition of chronological coincidences, especially with regard to the age of seven major sedimentary ruptures (those developed at about 24.5 Ma, 22 Ma, 16 Ma, 13.5 Ma, 9.5 Ma, 5.5 Ma, 3.3 Ma). Evolutionary sedimentary trends in both offshore Mediterranean areas and inland peripheral zones of the Iberian Peninsula show also striking coincidences regarding the chronology of major sedimentary breaks observed in continental successions. Paleoc1imatic curves for the Spanish continental Neogene display four relative temperature peaks indicative of warm c1imatic conditions (Late Agenian, Early-Middle Aragonian, Vallesian-Turolian, and Late Villafranchian) as well as five relatively dry periods (Early Ramblian, Middle-Late Aragonian, Middle Turolian, Late Ruscinian, and Middle Villafranchian ages).