Person:
Martín Chivelet, Javier

First Name

Javier

Last Name

Martín Chivelet

URI

https://hdl.handle.net/20.500.14352/75277

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Geológicas

Department

Geodinámica, Estratigrafía y Paleontología

Area

Estratigrafía

Identifiers

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Now showing 1 - 10 of 19

Comparison of speleothem fabrics and microstratigraphic stacking patterns in calcite stalagmites as indicators of paleoenvironmental change
(Quaternary International, 2016) Muñoz García, María Belén; Cruz, J.; Martín Chivelet, Javier; Ortega, Ana Isabel; Turrero, M.J.; López Elorza, Maialen
In the necessary task of obtaining high-resolution paleoclimate series from speleothems, the characterization of their internal microstratigraphy is a useful tool for: a) improving geochronology, and b) reaching a more complete knowledge of the speleothem formation and evolution through time and thus obtaining additional paleoenvironmental information. However, the development of standardized methodologies for microstratigraphic characterization is a pending task. In this paper, two different approaches allow construction of microstratigraphic logs for three stalagmites retrieved from two different caves. The logs correspond to vertical variations in speleothem fabrics and in microstratigraphic stacking patterns. The “fabrics logs” essentially provide information about the drip rate (sometimes used as a precipitation proxy) and the regularity or irregularity of each drip in the short-term. The “microstratigraphic stacking patterns logs” can be interpreted to obtain information about the changes in drip rates in the mid- and long-term. The results show a broad correlation between both kinds of logs that supports their validity as paleoenvironmental proxies. Fabrics formed under relatively constant and regular drips (columnar compact, open and elongated) usually constitute aggradational or progradational microstratigraphic stacking patterns. On the other hand, retractional stacking patterns are usually related with fabrics precipitated under more irregular drips (dendritic and columnar microcrystalline).However, this relation is not rigid and the information obtained from the logs is not equivalent, but complementary. The combination of both logs allows reconstruction of the hydrological history for each drip site. As all the obtained information derives directly from the drip conditions, drip effects result to be very important and can, in some cases, overwhelm the paleoclimate information recorded in each stalagmite.
Mg/Ca ratios measured by Laser Induced Breakdown Spectroscopy (LIBS): a new approach to decipher environmental conditions
(Journal of Analytical Atomic Spectrometry, 2015) García Escarzaga, Asier; Moncayo Martín, Samuel; Gutiérrez Zugasti, Igor; González Morales, Manuel R.; Martín Chivelet, Javier; Cáceres, Jorge Omar
The potential application of Mg/Ca ratios in top shells of the mollusc species Phorcus lineatus (Da Costa, 1778) obtained by Laser Induced Breakdown Spectroscopy (LIBS) have been evaluated as an environmental proxy to reconstruct paleotemperatures and season of capture of molluscs for the first time. All samples were collected from Cantabrian Sea (Spain). The results were compared with instrumental sea surface temperatures (SST) and with a known reliable proxy as oxygen isotope ratio (δ18Oshell) which is mainly dependent on SST, obtained from the same shells. The measurements were taken in two different biominerals of the shell (aragonite and calcite) resulting in a correlation between Mg/Ca ratios and SST of R2= 0.43 and 0.44, respectively. Mg/Ca ratios were also studied through a long sequence on three shells collected in autumn 2012. Results show variations in Mg/Ca ratios related to seasonal changes in SST through the year and a good correlation between Mg/Ca ratios and δ18Oshell in two shells (R2= 0.70 and 0.65, respectively).
Comparación del clima interglacial eemiense y holoceno en el norte de España a partir de los indicadores paleoclimáticos de estalagmitas de la Cueva del Cobre (Palencia)
(Geotemas, 2008) Muñoz García, María Belén; Martín Chivelet, Javier; Rossi Nieto, Carlos; Ford, D.C.; Schwarez, H.P.
El Eemiense se suele considerar un buen análogo del Holoceno a pesar de la diferente configuración orbital de cada época. La comparación de varios indicadores paleoclimáticos obtenidos en estalagmitas eemienses y holocenas de la Cueva del Cobre (Montaña Palentina) aporta datos que permiten verificar esta supuesta similitud. Los indicadores paleoclimáticos comparados son la tasa de crecimiento de las estalagmitas, las texturas de la calcita y los isótopos estables de oxígeno. En comparación con los holocenos, los espeleotemas eemienses son más grandes porque han crecido sin interrupción durante más tiempo, presentan una variedad menor de texturas de calcita y apenas registran láminas anuales. Además, ni las texturas de calcita ni la composición isotópica de oxígeno muestran signos de alteración diagenética. En función de estos indicadores se ha podido deducir que el clima de la zona de estudio fue durante el Eemiense ligeramente más cálido que durante el Holoceno y considerablemente más seco, contradiciendo las estimaciones más aceptadas del clima global para el Último Periodo Interglacial. El clima eemiense en la zona de estudio fue además más estable y tuvo una estacionalidad menos marcada que en los últimos 6000 años. El análisis de los cambios sincrónicos de estos indicadores ha permitido estimar una duración del Último Periodo Interglacial de ~21ka en esta zona.
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, Javier
El 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.
Determination of sea surface temperatures using oxygen isotope ratios from Phorcus lineatus (Da Costa, 1778) in northern Spain : Implications for paleoclimate and archaeological studies
(The Holocene, 2015) Gutiérrez-Zugasti, Igor; García-Escárzaga, Asier; Martín Chivelet, Javier; González-Morales, Manuel R.
Changes in oxygen isotope ratios from shell carbonates are mainly dependent on sea surface temperature, which enables the estimation of temperatures during periods of shell growth and helps to determine the season of the year when the mollusk died. The marine topshell Phorcus lineatus (Da Costa, 1778) is commonly found in Holocene archaeological deposits of Atlantic Europe and is one of the most abundant subsistence resources utilized during the Mesolithic in northern Spain. Before applying isotopic techniques to ancient samples, calibration of the past isotopic data and its variability must be performed through the study of modern specimens to test their potential as paleoclimate proxy and their suitability for determining the collection season. Although previous studies performed in the region highlighted the existing relationship between sea surface temperatures and isotopic signatures, no systematic works have been done so far. In this paper, calibration of modern P. lineatus shells from northern Spain was carried out using δ18O analysis. The results showed (1) the existence of a robust inverse correlation between instrumental temperatures (T meas) and δ18Oshell (R 2 > 0.9), accompanied by the lack of significant dependence from δ18Owater variations (R 2 = 0.06); (2) the existence of conditions of (or close to) isotopic equilibrium during the formation of the aragonite in the P. lineatus shells; and (3) that using mean annual δ18Owater values, past temperatures could be calculated with a maximum uncertainty of ±3°C. Moreover, results suggested that P. lineatus generally grew without substantial slow/cessation throughout the year, reflecting the four annual seasons. Therefore, our study not only confirms the potential of oxygen isotope analysis on P. lineatus for paleoclimate reconstruction and archaeological studies highlighted in previous studies but also shows for the first time that the aragonite of those shells grew under conditions of isotopic equilibrium, opening new avenues for future research.
Long-term hydrological changes in northern Iberia (4.9–0.9 ky BP) from speleothem Mg/Ca ratios and cave monitoring (Ojo Guaren˜a Karst Complex, Spain)
(Environmental Earth Sciences, 2015) Cruz, J. A.; Turrero, M. J.; Cáceres, Jorge Omar; Marín Roldán, Alicia; Ortega, A. I.; Garralón, A.; Sánchez, L.; Gómez, P.; Muñoz García, María Belén; Edwards, R. L.; Martín Chivelet, Javier
An absolute-dated stalagmite from Kaite Cave (Ojo Guaren ̃ a Karst Complex, N Spain) provides a nearly continuous, high-resolution record of a proxy of regional precipitation patterns through the 4.9–0.9 ka BP interval. This record is based on the Mg/Ca ratio of the calcite and its variation through the stalagmite stratigraphy, which is interpreted to be primarily driven by changes in precipi- tation amount. The calibration of the proxy is supported by the present-day monitoring carried out in the cave for the last 10 years, which reveals a robust inverse relationship between the inter-annual/inter-decadal variability of rain- fall and the Mg concentration of dripwaters and precipi- tating speleothems. The record of paleoprecipitation, based on 2400 Mg/Ca measurements, shows strong variability at inter-annual to inter-decadal scales, and more subtle but significant changes at secular to millennial scales. This long-term paleohydrological evolution outlines five suc- cessive intervals with consistent trends, which are bounded by abrupt shifts in the regional precipitation. These shifts took place at 4.65, 4.2, 2.6, and 1.3 ka BP. Significantly, the intervals of maximum precipitation of the whole record (around 4.9–4.65, 2.6–2.45, and 1.3–1.1 ka BP) can be related with episodes of minimum solar activity and cor- related with cold climatic events elsewhere.
Modified fischer plots as graphical tools for evaluating thickness patterns in stratigraphic successions
(Journal of Geoscience Education, 2000) Martín Chivelet, Javier; Osleger, D.A.; Montañez, I.P.
Fischer plots are a simple, objective graphical tool for illustrating thickness trends in cyclic successions and are particularly amenable for use in stratigraphy courses. Their utility in stratigraphic analysis is making its way into textbooks, and the large body of literature discussing the strengths and limitations of Fischer plots provides fertile ground for discussions about cyclic successions and concepts such as time-versus-thickness in undergraduate and graduate classes. In an effort to enhance the utility of Fischer plots and to reduce some of their inherent limitations, we suggest two modifications to the fundamental technique. First, we suggest that the cumulative departure from mean cycle thickness should be plotted against the individual measured cycle thicknesses rather than the unit-mean cycle thickness. This time-independent modification has the advantage of being directly comparable to measured thicknesses of the stratigraphic columns from which they were derived and also may, in some cases, enhance the sharpness of the waveform. The second suggested correction to the traditional Fischer plot is to decompact individual lithofacies prior to plotting. A correction for compaction is especially useful in successions that consist of heterogeneous facies that exhibit clear differences in compaction through time. In certain cases, decompacted Fischer plots reveal higher magnitude changes in thickness patterns that may not otherwise be recognizable in traditional or modified Fischer plots. In the spirit of 'the only way to understand it is to do it,' we provide a simple LISP subroutine for automatically drawing each type of Fischer plot under any Autocad environment.
Middle-Upper Triassic carbonate platforms in Minorca (Balearic islands): Implications for Western Tethys correlations
(Sedimentary Geology, 2014) Escudero Mozo, María José; Martín Chivelet, Javier; Goy Goy, Antonio; López Gómez, José Luis
In order to progress in the knowledge of the Middle to Upper Triassic evolution of the western Tethys realm, an integrated approach which includes new sedimentological, sequence stratigraphic and biostratigraphic data, has been accomplished in the carbonate marine successions (Muschelkalk facies) of that age in Minorca (Balearic Islands, Spain). The new biostratigraphy, which includes six successive ammonoid biozones, allowed to assign these carbonate successions to the uppermost Anisian–lower Carnian interval. The integration of the new chronostratigraphic framework with the sedimentological analysis allowed to recognize five main successive stages of carbonate platform evolution: 1) Initial marine transgression and shallow ramp development (uppermost Anisian); 2) Carbonate ramp drowning (Anisian–Ladinian boundary); 3) Prevalence of open sea conditions (Ladinian–early Carnian); 4) Abrupt sea-level drop (intra-lower Carnian) and; 5) Shallow carbonate ramp and transition to sabkha systems (Keuper facies). Furthermore, the sequence stratigraphic analysis allowed to divide some of these stages into depositional sequences. Minorca was located in the westernmost Tethys area during the Triassic, in a key paleogeographic location close to the present-day Iberia, Sardinia and the Cottian and Southern Alps. The new data have allowed an interregional comparative analysis among these areas, with recognition of major suprarregional events and episodes in the framework of the western Tethys evolution.
Speleothem architectural analysis: integrated approach for stalagmite-based paleoclimate research
(Sedimentary Geology, 2017) Martín Chivelet, Javier; Muñoz García, María Belén; Cruz, Juncal A.; Ortega Martínez, Ana Isabel; Turrero Jiménez, María Jesús
Carbonate stalagmites have become increasingly attractive to Quaternary paleoclimate research, as they can be accurately dated by radiometric methods and concurrently yield high-resolution multi-proxy records of past climate conditions. Reliable series however require the precise characterization of stalagmite internal icrostratigraphy,4 a task too often poorly accomplished despite the recent advances in speleothem research. This weakness is due to the lack of a robust integrative methodological framework capable of integrating the wide range of petrographical and micro-stratigrafical methods currently used in speleothem characterization. For covering this need, this review introduces the Speleothem Architectural Analysis (SAA), a holistic approach inspired in well-established stratigraphic procedures such as the architectural element analysis and the sequence stratigraphy, commonly used by geoscientists for categorizing internal stratigraphic heterogeneities in sedimentary deposits. The new approach establishes a six-fold hierarchy of speleothem architectural elements and their bounding surfaces: individual crystallites (1st order), single growth layers (2nd order), speleothem fabrics (3rd order), stacking patterns sets (4th order), morphostratigraphic units (5th order), unconformity-bounded units and major unconformities (6th order). Each category of architectural element is formed in a different range of time, from intervals as short as a year/season to others of centuries or millennia. The SAA, which has the capability of incorporating any petrographic or stratigraphic classification, provides a useful, systematic, and versatile tool for unraveling the complexities of speleothem growth, and thus for genetically interpreting stalagmites in a multi-temporal scale. A detailed speleothem stratigraphy must be the basis for performing robust reconstruction of paleoclimate series. They should precede and accompany any work focused in absolute age dating or in reconstructing paleoclimate by means of any geochemical proxy
Métodos de análisis del contenido en carbonatos de series hemipelágicas: estudio comparado en la Formación Represa (Albiense superior, Prebético)
(Geotemas, 2016) Coruña López, Francisco; Santiago Buey, Cristina de; Martín Chivelet, Javier; López De Andrés, María Sol
En este trabajo se realiza un análisis comparativo de cuatro técnicas de determinación del porcentaje de carbonatos en rocas sedimentarias de composición mixta carbonático-siliciclástica: 1) difracción de rayos-X, 2) determinación de carbono orgánico total, 3) pérdida por calcinación, y 4) calcimetría. Para ello se aplican a la Formación Represa (Albiense superior) en la Serra dels Almaens, en el Prebético de Alicante. Esta serie está formada por 450 m de facies rítmicas hemipelágicas de calizas y margas. Los resultados a lo largo de la serie de estas cuatro técnicas son muy similares, si bien la pérdida por calcinación es la técnica más inexacta e imprecisa, por su dependencia de la mineralogía de la muestra. Por el contrario, la difracción de rayos X aparece como la técnica más adecuada en conjunto, ya que, a su alta precisión y exactitud se le suma la información mineralógica de la muestra. La calcimetría tiene la ventaja de su sencillez y rapidez, a costa de una información más incompleta. El análisis del carbono orgánico total admite muestras de menor tamaño y da resultados más exactos, pero también es la técnica más costosa y la exactitud de los resultados está condicionada a la ausencia de otros carbonatos distintos del carbonato cálcico.