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 89

Earthquake-induced soft-sediment deformation structures in Upper Jurassic open-marine microbialites (Neuquén Basin, Argentina)
(Sedimentary Geology, 2011) Martín Chivelet, Javier; Palma, Ricardo Manuel; López Gómez, José; Kietzmann, Diego A.
Penecontemporaneous decimetre-scale soft-sediment deformation structures are reported from the basal part of the Upper Jurassic–Lower Cretaceous Vaca Muerta Formation, in the Malargüe–Las Leñas area of the back-arc Neuquén Basin (Mendoza Province, Central Andes). The deformed interval (Amarillas bed) is only 0.3 to 0.9 m thick but occurs in a wide area, larger than 1500 km2. Its age, determined by ammonite biostratigraphy, is Early Tithonian. The soft-sediment deformation structures were generated in finely laminated, partially consolidated, organicrich, carbonate microbialites that were deposited in open-marine, poorly oxygenated settings, apparently devoid of any significant slope. Those structures include boudins of different sizes and complexity, a variety of folds, normal (listric) dm-scale faults, sub-horizontal detachment surfaces and other features, which are part of several larger-scale, complex slump structures. Deformation was dominantly plastic but near to the ductile–brittle field transition. On the basis of the observed soft-deformation structures, their geographic distribution, their lateral homogeneity, and the geodynamic framework of the basin in which it was generated, the Amarillas bed can be tentatively attributed to a large, intermediate-depth earthquake that occurred within the plate that subducted beneath the Andean continental margin and the Neuquén back-arc basin.
Sedimentology and sequence stratigraphy of a Tithonian–Valanginian carbonate ramp (Vaca Muerta Formation): A misunderstood exceptional source rock in the Southern Mendoza area of the Neuquén Basin, Argentina
(Sedimentary geology, 2014) Kietzmann, Diego A.; Palma, Ricardo Manuel; Riccardi, A.C.; Martín Chivelet, Javier; López Gómez, José
The Vaca Muerta Formation (early Tithonian–early Valanginian) is a rhythmic succession of marls and limestones, cropping out in the Neuquén Basin, west-central Argentina. This lithostratigraphic unit was traditionally interpreted as basinal to slope deposits. Detailed facies analysis allows to differentiate seven facies associations, representing basinal to middle ramp facies of a homoclinal ramp system prograding westward from the eastern margin, and slope facies attributed to a distally steepened rampsystemthat progrades eastward fromthe Andean volcanic arc in the west. Two sequence hierarchies are recognized: five third order depositional sequences, and fifteen fourth order high-frequency sequences. Fluctuations in organic matter content within the Vaca Muerta Formation suggest relationship with depositional sequences, finding the highest values associated with transgressive systemtracts. This work represents an important advance in the understanding of the sedimentary and stratigraphic evolution of this exceptional unconventional reservoir. Our sequence stratigraphic approach contributes to the understanding of the relationship between organic matter, facies, and sea-level changes.
Discontinuidades estratigráficas regionales en las sucesiones hemipelágicas finicretácics del Prebético (sector Jumilla-Callosa-Aspe)
(Journal of iberian geology, 2003) Chacón, B.; Martín Chivelet, Javier
Human forager response to abrupt climate change at 8.2 ka on the Atlantic coast of Europe
(Scientific reports, 2022) García Escarzaga, Asier; Gutiérrez Zugasti, Igor; Marín Arroyo, Ana B.; Fernandes, Ricardo; Núñez de la Fuente, Sara; Cuenca Solana, David; Iriarte, Eneko; Simões, Carlos; Martín Chivelet, Javier; González Morales, Manuel R.; Roberts, Patrick
The cooling and drying associated with the so-called ‘8.2 ka event’ have long been hypothesized as having sweeping implications for human societies in the Early Holocene, including some of the last Mesolithic hunter-gatherers in Atlantic Europe. Nevertheless, detailed ‘on-site’ records with which the impacts of broader climate changes on human-relevant environments can be explored have been lacking. Here, we reconstruct sea surface temperatures (SST) from δ18O values measured on subfossil topshells Phorcus lineatus exploited by the Mesolithic human groups that lived at El Mazo cave (N Spain) between 9 and 7.4 ka. Bayesian modelling of 65 radiocarbon dates, in combination with this δ18O data, provide a high-resolution seasonal record of SST, revealing that colder SST during the 8.2 ka event led to changes in the availability of different shellfish species. Intensification in the exploitation of molluscs by humans indicates demographic growth in these Atlantic coastal settings which acted as refugia during this cold event.
Strong links between Saharan dust fluxes, monsoon strength, and North Atlantic climate during the last 5000 years
(Science Advances, 2021) Cruz, J. A.; McDermott, Frank; Turrero Jiménez, María Jesús; Edwards, R. Lawrence; Martín Chivelet, Javier
Despite the multiple impacts of mineral aerosols on global and regional climate and the primary climatic control on atmospheric dust fluxes, dust-climate feedbacks remain poorly constrained, particularly at submillennial time scales, hampering regional and global climate models. We reconstruct Saharan dust fluxes over Western Europe for the last 5000 years, by means of speleothem strontium isotope ratios (87Sr/86Sr) and karst modeling. The record reveals a long-term increase in Saharan dust flux, consistent with progressive North Africa aridification and strengthening of Northern Hemisphere latitudinal climatic gradients. On shorter, centennial to millennial scales, it shows broad variations in dust fluxes, in tune with North Atlantic ocean-atmosphere patterns and with monsoonal variability. Dust fluxes rapidly increase before (and peaks at) Late Holocene multidecadal- to century-scale cold climate events, including those around 4200, 2800, and 1500 years before present, suggesting the operation of previously unknown strong dust-climate negative feedbacks preceding these episodes.
Fabric and Fluid Inclusions Characterization of a Stalagmite from Eastern Spain: A Precondition for Noble Gas Analysis by Step-Crushing Methodology
(Minerals, 2024) López Elorza, Maialen; Weißbach, Therese; Muñoz García, María Belén; Kluge, Tobias; Aeschbach, Werner; Martín Chivelet, Javier
Fluid inclusions in stalagmites are becoming increasingly important for paleoclimate research. Within this framework, noble gas thermometry, based on noble gases dissolved in water from fluid inclusions, provides quantitative estimations of cave air paleotemperature. Two major issues of Noble Gas Temperature (NGT) determination on speleothems are (1) the potential lack of enough water for the analysis and (2) the presence of trapped gas not dissolved in water that can be released during the analysis from biphasic or all-gas fluid inclusions, as its contribution to the bulk noble gas signal can hinder NGT results. Although the step-crushing method helps to reduce the second issue, it also decreases the amount of water available for the calculations. In order to obtain reliable NGT results with low uncertainties, a major challenge is still to reach a balance between sufficient water for analysis and a small amount of “atmospheric” gas. The difficulty is that the extraction process cannot be standardized since it strongly depends on the type of sample. The objective of this work is to investigate how the characteristics of the speleothem can determine the adequacy of the extraction process. For this purpose, we consider a stalagmite from a Mediterranean cave that consists of columnar elongated calcite and contains a significant quantity of fluid inclusions, which suggests good potential for NGT analysis. Results, however, were poorly satisfactory. Trying to understand the source of the problems, an integrated study of petrography and petrophysical features was performed. The samples were found to be different depending on the stage of coalescence of crystals and thus separated into “open” and “closed” fabrics. Classic petrographic analysis and non-destructive (nuclear magnetic resonance) techniques were used to characterize the type and amount of fluid inclusions present in both types of fabrics. The study indicates that the closed fabric (total coalescence of calcite crystals) has most water trapped in water-filled, small intracrystalline fluid inclusions that usually contain very little gas. This fabric is very suitable for NGT determination, but since the amount of water is quite small, the sample should be crushed in only one step with a large number of beats to break all the inclusions. In contrast, samples with open fabric (partial coalescence of calcite crystals) contain a higher amount of water and, also, gas-filled large intercrystalline fluid inclusions. For this fabric, step-crushing of the sample is necessary. However, the low amount of water left for the second and third crushings could lead to flawed NGT results. Thus, we suggest modifying the method to get rid of part of the gas in the first crushing while leaving enough water for the following steps. This work shows the importance of characterizing speleothems and fluid inclusions, including their petrography and petrophysical characteristics, before starting NGT analysis, allowing the selection of the most favorable samples and the customization of the step-crushing procedure.
Vertebrate ichnofauna from Sierra de las Cabras tracksite (Late Miocene, Jumilla, SE Spain). Mammalian ichnofauna
(Journal of iberian geology, 2022) Herrero, Cayetano; Herrero, Emilio; Martín Chivelet, Javier; Pérez Lorente, Felix
Upper Miocene sedimentary deposits of Sierra de las Cabras in the Prebetic Ranges (Jumilla, Región de Murcia, Spain) yield a exceptional fossil site of diverse vertebrate ichnofauna, including mammals and birds. This paper presents a detailed study of those ichnites of that site which correspond to mammals. The footprints are located in stratigraphic surfaces found in a thin marly limestone succession that can be assigned to the latest Tortonian to earliest Messinian. The mammalian record consists of 324 footprints (included in trackways, pairs, groups and isolated ichnites) of diverse vertebrates, including: Hippipeda, Rhynoceripeda, Canipeda, Felipeda, Ursipeda, Rodentipeda, as well possible Suipeda. The ichnites were imprinted on wet and cohesive marly carbonate mud, deposited in a semi-arid wetland with relevant freshwater influx. The fossil site, cleaned and protected some years ago but herein studied by the first time, add together the nearby Hoya de la Sima site (Hippipeda, Pecoripeda, Bestiopeda and Paracamelichnium, and probably proboscidean ichnites) to conform an exceptional record of Late Miocene ichnofauna in southern Iberia.
Peritidal cyclic sedimentation from La Manga Formation (Oxfordian), Neuquén Basin, Mendoza, Argentina
(Journal of South American earth sciences, 2013) Palma Durán, Ricardo; Kietzmann, Diego A.; Bressan, Graciela Susana; Martín Chivelet, Javier; López Gómez, José; Farias, María E.; Iglesias Llanos, María P.
The La Manga Formation consists of marine carbonates and represents most of the sedimentary record of the Callovian-Oxfordian in the Neuquén Basin. Three localities in the southern Mendoza province were studied and their cyclicity was determined by means of facies analysis and their vertical arrangement. Facies of inner ramp, that were deposited in extremely shallow-water environments with intermittent subaerial exposures have been broken down into shallow subtidal, and intertidalesupratidal environments. Shallow subtidal facies are arranged into decimetre scale upward-hallowing cycles composed of marls, laminated or massive mudstones or bioclastic wackestones and intraclastic wackestone-packstones. Intertidal-supratidal centimetre-scale cycles consist of an upward-shallowing succession of restricted facies, overlaid by horizontal or crinkle microbial laminites, flat pebble conglomerates or breccias beds. The defined cycles show a shallowing upward trend in which the evidence of relative sea-level lowering is accepted. The interpretation of Fischer plots allowed the recognition of changes in accommodation space.
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, M.
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.
Late Quaternary climatic and environmental conditions of northern Spain: An isotopic approach based on the mammalian record from La Paloma cave
(Palaeogeography, Palaeoclimatology, Palaeoecology, 2015) Domingo Martínez, Laura; Pérez Dios, Patricia; Hernández Fernández, Manuel; Martín Chivelet, Javier; Ortiz, José Eugenio; Torres Pérez-Hidalgo, Trinidad José de
La Paloma cave (Asturias, northern Spain) stands out as one of the most notable prehistoric sites of the northern Iberian sector due to the richness of its archaeo-paleontological material, spanning a complete Magdalenian–Azilian sequence (~ 20,300–12,900 cal years BP). The abundance, diversity and good preservation of mammalian remains make of La Paloma site an excellent location to characterize paleoclimatic, paleoecological and paleoenvironmental conditions from a biogeochemical standpoint. Stable isotope analyses performed on tooth enamel (δ13Cen, δ18OCO3, δ18OPO4) and bone collagen (δ13Ccoll, δ15N) of a suite of herbivore, carnivore and omnivore species did not yield significant variations across the stratigraphic sequence, likely pointing to prevalent and stable local conditions, with i) no major vegetation turnover, ii) maintenance of hydrological conditions, and iii) relatively constant soil activity, in spite of the synchrony of the La Paloma temporal context with global events, such as the end of the Last Glacial Maximum, the Heinrich Event 1 and the Bølling–Allerød oscillation. La Paloma δ13Cen and δ13Ccoll values are within the expected range for C3 mixed woodland–mesic C3 grassland conditions. Overall, bovids (large Bovidae, ibex and chamois) show higher δ13Cen, δ13Ccoll and δ15N values than cervids (red deer and roe deer), indicating a preference for more open environments in the former. Horse δ13C values are undistinguishable from those of red deer and point to a mixed-feeding behavior. Horse low δ15N values may be indicative of a diet with a low protein content. Bayesian mixing model results yielded differences in carnivore resource use, with wolf preying on all ungulates and red fox preferentially incorporating roe deer. Stable paleoenviromental conditions during the latest Pleistocene at the La Paloma area may have favored the persistence of a stable mammalian community structure, supporting the idea of the existence of refuge areas in the northern Iberian sector throughout the late Quaternary glacial–interglacial dynamics.