Person: Martín Chivelet, Javier
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First Name
Javier
Last Name
Martín Chivelet
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Geológicas
Department
Geodinámica, Estratigrafía y Paleontología
Area
Estratigrafía
Identifiers
7 results
Search Results
Now showing 1 - 7 of 7
Item Major palaeoenvironmental perturbation in an Early Aptian carbonate platform: Prelude of the Oceanic Anoxic Event 1a?(Sedimentary Geology, 2011) Najarro, María; Rosales, Idoia; Martín Chivelet, JavierThe Early Aptian Oceanic Anoxic Event (OAE 1a) was characterized by intensified greenhouse climate conditions, widespread accumulation of organic deposits in open-marine settings, major perturbations in the C cycle and a generalized increase in terrestrial runoff. Sedimentological, diagenetic and chemostratigraphic analyses of Lower Aptian platform carbonates from the North Cantabrian basin (N Spain) illustrate the regional impact and effects of those global conditions on shallow marine environments. The studied interval outlines four stages of platform evolution. Stage 1 (earliest Bedoulian) is defined by an initial rapid marine transgression that led to deposition of shallow water oligotrophic photozoan skeletal assemblages, and by a later interval of subaerial exposure. Stage 2 (early Bedoulian) starts with a rapid transgression followed by deposition of grainstones that yield heterozoan assemblages, more typical of mesotrophic conditions, along with ferruginized oolites. Stage 3 (early Bedoulian) is defined by the drowning of the carbonate platform and subsequent deposition of open-marine marls, which are thought to represent the local expression of the OAE 1a. Finally, stage 4 shows the return of shallow water photozoan carbonate sedimentation. The carbonate O and C stable isotope records have revealed prominent negative excursions during deposition of the marly interval of the stage 3, which may be associated with the important global changes that occurred at the onset of the OAE 1a. The change in skeletal assemblages that preceded the isotopic excursions and the platform drowning documents conditions of environmental stress caused by a combination of local and global factors. The global change, coupled with increased basin subsidence, triggered the drowning of the platform by progressive reduction of the growth potential of the carbonate factory.Item Ciclos carbonatados submareales-perimareales de alta frecuencia del Aptiense inferior (Fm. San Esteban, cuenca Vasco-Cantábrica): registro de cambio climático(Geotemas, 2016) Rosales, Idoia; Najarro, María; López-Cilla, I.; Martín Chivelet, JavierEl análisis detallado de facies de las calizas de la Formación San Esteban del Aptiense inferior de Cantabria ha permitido caracterizar 15 tipos de litofacies depositadas en ambientes submareales a supramareales. Las facies se organizan en ciclos somerizantes que culminan con superficies de exposición subaérea, evidenciado variaciones relativas del nivel del mar de alta frecuencia/baja amplitud. Se distinguen dos tipos de ciclos en función de las facies y naturaleza de las superficies que los culminan. Los ciclos Tipo-1 están dominados por facies submareales. La secuencia ideal comienza con rudstone bioclástico-intraclástico, seguido de wackestone de Chondrodonta, floatstone de rudistas, boundstone de rudistas y mudstone de milólidos. El techo es una superficie neta con bioturbación y marcas de raíces estilo pseudomicrokarst. Los ciclos Tipo-2 comienzan con floatstone oncolítico-litoclástico, seguido de floatstone de rudistas, packstone-grainstone de foraminíferos, boundstone de rudistas y finalmente rudstone oncolítico, mudstone fenestral y/o estromatolitos laminares a hemiesféricos. Culmina con rasgos subaéreos de desecación y conglomerados calcáreos de cantos negros con microestructura alveolar y rizolitos calcificados. Los ciclos Tipo-1 caracterizaron condiciones ambientales húmedas, mientras que los de Tipo-2 caracterizaron condiciones semi-áridas. La evolución vertical de los ciclos refleja una transición climática de tipo greenhouse a otra coolhouse tras el OAE-1a.Item Sulcusina iberica n. ichnogen., n. ichnosp., a new crustacean microcoprolite from the Upper Cretaceous of Spain(Cretaceous Research, 2017) Schlagintweit, Felix; Muñoz Moreno, Alejandro; Martín Chivelet, Javier; Rosales, IdoiaThe new crustacean microcoprolite Sulcusina iberica n. ichnogen., n. ichnosp., is described from the Upper Cretaceous Alarcon Formation (?uppermost Cenomanian to ?lower Coniacian) of the Southern Iberian range. The new ichnogenus is characterized by rod-shaped bodies with parallel-running longitudinal canals (without interconnecting lines) of rounded transverse sections within the symmetry plane. Characteristic is the presence of a central longitudinal furrow (or canal) that extends to the middle of the microcoprolite, without any connection to the laterally grouped canals of usually lower diameter. The latter display a circular outline in transverse sections. Sulcusina n. ichnogen. can be compared to some extant with both Helicerina Bronnimann € & Masse and Lercarina Senowbari-Daryan. The new microcoprolite occurs in monotypic grainstones together with some thin-walled miliolids and ostracods ascribed to a peritidal facies.Item Palaeoenvironmental Changes and C-Isotope Stratigraphy in the Alarcón Formation Stratotype (Upper Cenomanian–Lower Coniacian), Iberian Ranges, Spain(STRATI 2013 : First International Congress on Stratigraphy At the Cutting Edge of Stratigraphy, 2014) Muñoz-Moreno, A.; Domínguez-Morales, M.; L.M. Robredo, Luz M.; Rosales, Idoia; Martín Chivelet, Javier; Rocha, Rogério B.; Pais, João; Kullberg, José Carlos; Finney, StanleyThis study analyses the sedimentary facies, palaeosols, and δ13C stratigraphy of the Alarcón Formation in its stratotype in the Iberian Ranges (Spain). The aim is to characterize the palaeoenvironmental changes that occurred in the shallow-marine carbonate environments of central Iberia during the late Cenomanian to early Coniacian. These changes, recorded in seven transgressive–regressive cycles, are interpreted in the framework of regional sea-level variations, local subsidence, and climate. The possible influence of supraregional changes, such as those related to Oceanic Anoxic Event 2 (OAE2), on the sedimentary succession of the Alarcón Formation is also analysed and discussed.Item Caracterización y evolución de los fluidos diagenéticos que afectaron a los carbonatos del Aptiense superior del noroeste de la cuenca Vasco-Cantábrica (Fm. Reocín)(Geotemas, 2016) López-Cilla, I.; Rosales, Idoia; Gasparrini, Marta; Martín Chivelet, JavierEl estudio combinado de microtermometría de inclusiones fluidas, geoquímica isotópica y petrología de las múltiples fases de dolomitización y cementación de calcita y dolomita que afectan a la Formación Reocín (Aptiense superior, noroeste de la cuenca Vasco-Cantábrica), ha permitido reconstruir la evolución de los fluidos durante la diagénesis de enterramiento y posterior exhumación orogénica de la cuenca. Durante la diagénesis temprana tuvo lugar la primera fase de dolomita (D1) y de cementos de calcita (C1, C2), a partir de fluidos meteóricos evolucionados o mezcla de fluidos. El segundo evento importante de flujo de fluidos durante el enterramiento dio lugar a la formación de dolomía de reemplazamiento (D2) y de recristalización (D3) y a cementos saddle de dolomita (D4, D5), que muestran un amplio rango de salinidades y temperaturas de nucleación relativamente bajas, lo que sugiere la interacción de fluidos que varían entre aguas marinas evolucionadas hasta salmueras altamente evaporadas. Este evento estuvo relacionado con la precipitación de sulfuros (mineralizaciones de Zn-Pb). El tercer evento de fluidos causó la precipitación de calcita (C3) que muestra muy bajas salinidades y las temperaturas de entrampamiento más altas, lo que sugiere precipitación a partir de la circulación de un fluido meteórico calentado en profundidad. La última fase diagenética está relacionada con un fluido frío, no-salino y oxidante, que causó la precipitación de calcita (C4), recristalización de la dolomita a calcita (dedolomita) y oxi-hidróxidos de Fe.Item Proliferación de Microcodium durante el tránsito Cenomaniense-Turoniense en el Sur de Iberia: ¿consecuencia del OAE2 en zonas emergidas?(Geogaceta, 2015) Muñoz-Moreno, Alejandro; Martín Chivelet, Javier; Rosales, IdoiaEn el sur de Iberia (Cordillera Ibérica meridional y Prebético) el tránsito Cenomaniense-Turoniense está definido por una sucesión de carbonatos marinos muy someros que presentan abundantes evidencias de exposición subaérea y paleosuelos (Fm.Alarcón). En esta sucesión se registra la primera aparición conocida en Iberia de Microcodium. Esta aparición es abrupta y podría estar relacionada con los cambios ambientales asociados a la perturbación global del ciclo del carbono que indujo el evento de anoxia oceánica OAE2.Item Organic geochemistry, stable isotopes, and facies analysis of the Early Aptian OAE—New records from Spain (Western Tethys)(Palaeogeography, palaeoclimatology, palaeoecology, 2012) Quijano López, María Luisa; Castro Jiménez, Jose Manuel; Pancost, Richard D.; Gea Guillén, Ginés Alfonso; Najarro, María; Aguado Merlo, Roque; Rosales, Idoia; Martín Chivelet, JavierThe Early Aptian Oceanic Anoxic Event (OAE1a) is a time interval characterized by increased organic carbon accumulation in marine sediments, notable sedimentary and biotic changes, and abrupt carbon-isotope excursions indicative of significant major palaeoenvironmental changes linked to a perturbation in the global carbon cycle. Here we present the study of four sections recording the OAE1a (Early Aptian) in Spain, which are located in two broad basins respectively located in the South and the North of Iberia: the Southern Iberian Palaeomargin (Carbonero, La Frontera and Cau sections) and the Basque–Cantabrian Basin (Puentenansa section), which represent depositional settings ranging from shallow marine (distal ramp -Cau- and drowned platform -Puentenansa-) to pelagic environments (Carbonero, La Frontera). Biomarker compositions, C-isotope profiles, biostratigraphic data and facies analysis from the four sections are correlated and integrated. The C-isotope curves all present a clear negative excursion followed by a positive shift. The integration of the C-isotope curves with the biostratigraphic data has been used to correlate the studied sections and to tentatively identify the eight segments formerly proposed from the Alpine domain, and subsequently identified in sections worldwide. Four main groups of compounds are present in all sections: n-alkanes, isoprenoids, hopanes and steranes. n-Alkanes and acyclic isoprenoids (pristane and phytane) are dominant in most samples. The hopanes are represented by a range of C27 to C35 components,with the specific isomers varying amongst the sections due to differences in thermal maturity. Steranes occur as a range of C27, C28 and C29 isomers, whereas diasteranes only occur in the most thermally mature section (Carbonero). Other compounds of interest include gammacerane and dinosterane. Differences in thermal maturity appear to be the first order control on different biomarker assemblages amongst the studied sections. The Carbonero section is thermally mature, whereas the nearby La Frontera and Cau sections are immature. Puentenansa has intermediate values. Organic matter is derived from a range of terrestrial, marine and bacterial sources. The dominance of the C29 sterane isomers in all sections suggests a strong contribution from higher plants. The presence of gammacerane indicates water column stratification, and high C29/C30 hopane ratios suggest anoxia at the water/sediment interface, respectively. Sedimentologic analysis also suggests anoxic conditions during sedimentation, but evidence for strong and persistent water column anoxia is equivocal. The correlation of the sections reveals that sedimentation of organic-rich facies started earlier in pelagic and later in the shallow marine settings, which can be related to an expansion of the favorable conditions for organic matter accumulation and preservation from deep marine waters to shallower platform environments during the development of OAE1a.