Person: Santisteban Navarro, Juan Ignacio
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First Name
Juan Ignacio
Last Name
Santisteban Navarro
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Geológicas
Department
Geodinámica, Estratigrafía y Paleontología
Area
Estratigrafía
Identifiers
22 results
Search Results
Now showing 1 - 10 of 22
Item Combining allostratigraphic and lithostratigraphic perspectives to compile subregional records of fluvial responsiveness: The case of the sustainably entrenching Palancia River watershed (Mediterranean coast, NE Spain)(Geomorphology (Amsterdam), 2011) Houben, Peter; Hoinkis, Ralf; Santisteban Navarro, Juan Ignacio; Salat, Christina; Mediavilla López, Rosa MaríaWe use a combined allostratigraphic and morpholithostratigraphic approach to establish a relative stratigraphy of macroscale sediment-landform units in the Mediterranean Palancia River watershed (986-km2, NE Spain). Four alloformations signifying important changes in (sub)regional scale geomorphic valley-floor evolution were identified based on data from 1120 field sites and age determinations, and from analyzing high resolution geodata. The formation of the widespread and thick Pleistocene alloformation can be attributed to climatically-induced excessive sediment supply and flood activities during Pleistocene cold intervals — rather than representing time-lagging response to Plio/Pleistocene neotectonic uplift. Triggered by the turn to Holocene climatic conditions, three successively inset alloformations illustrate how stream grading and floodplain narrowing continuously have progressed over the Holocene. The overall degradational valley-floor evolution in the Holocene is interpreted as a response to the antecedent, overly valley-floor aggradation. Allostratigraphic and morphostratigraphic data suggest that the abandonment of the two earlier Holocene alloformations geomorphologically represents a pulsed turn toward intensified entrenchment rather than pulsed sedimentation. The most important benefit of amalgamating allostratigraphic and (morpho)lithostratigraphic concepts is that allostratigraphic ordering provides a formally conclusive approach to scale up (morpho)lithostratigraphic information from the reach scale to much larger scales of geographical extent. Consequently, applying allostratigraphic principles opens a perspective to moving forward toward analyzing the relationships between climate, neotectonics, sea level change, human impact, and fluvial response in coupled hinterland-coastal systems that require to evaluate sedimentary information at larger spatial scales.Item Holocene floods in a complex fluvial wetland in central Spain: Environmental variability, climate and time(Global and Planetary Change, 2019) Santisteban Navarro, Juan Ignacio; Mediavilla, Rosa; Galán de Frutos, L.; López Cilla, IgnacioThe study of flooding can be complex as it involves dynamic systems (rivers) characterized by high variability in time and space. To minimize the effects of these handicaps, we merge several records from different locations across the hydrographic basin of the Upper Guadiana River (central Spain) and use multiple proxies. The comparison of three nearby cores by means of the facies, stratigraphic correlation and geochemical indexes allows us to differentiate local environmental changes related to the natural behaviour of the system (autocyclic) from those driven by external forcings (allocyclic). The facies and facies sequence analyses allow long-term paleohydrological trends to be reconstructed and parameters that are used to identify flooding events to be determined. Si (proxy for siliciclastic supply) and Ca/S (proxy for water budget/level) show trends that can be related to facies sequences and long-term variations. Si/Al is used as a sorting proxy (transport efficiency). To analyse the relative changes in sediment discharge and transport efficiency, these proxies are compared with water budget level, represented by (Si/Al)/(Ca/S) (sorting vs. water level) and Si/(Ca/S) (siliciclastic discharge vs. water discharge). We were able to define local, major and minor regional flood events/periods and events by relating sequence boundaries to the occurrence of environmental conditions related to high energy events (relative/absolute sorting, water level, sediment discharge) across multiple cores. Comparison to other studies around the western Mediterranean basin allows us to identify common periods of flooding at 9000–8400 cal. BP, 7700–7100 cal. BP, 6400–6200 cal. BP, 4900–3700 cal. BP, 3500–3300 cal. BP, ca. 2600 cal. BP, ca. 2000 cal. BP, ca. 1500 cal. BP and 1000–300 cal. BP. For the long-term evolution, it seems that changes in insolation during the Holocene could have played a role in controlling the hydrology. However, determining the drivers of higher-frequency variation is more challenging due to uncertainties in the chronologies and local differences. Nevertheless, some degree of correlation among these flooding periods and higher frequency changes in irradiance, temperature and NAO is observed.Item Holocene offshore tsunami archive – Tsunami deposits on the Algarve shelf (Portugal)(Sedimentary Geology, 2023) Feist, Lisa; Costa, Pedro J.M.; Bellanova, Piero; Bosnic, Ivana; Santisteban Navarro, Juan Ignacio; Andrade, César; Brückner, Helmut; Duarte, João F.; Kuhlmann, Jannis; Schwarzbauer, Jan; Vött, Andreas; Reicherter, KlausThe well-known 1755 CE Lisbon tsunami caused widespread destruction along the Iberian and northern Moroccan coastlines. Being affected by the powerful 1755 CE Lisbon tsunami, the southwestern Algarve shelf provides environments for detecting offshore tsunami imprints. Our multidisciplinary investigations (hydroacoustics, sedimentology, geochemistry, radiocarbon dating) of the Holocene sediments have revealed tsunami deposits linked to this tsunami and a ca. 3600 cal yr BP event. The latter event is until now unidentified in Portugal. Both event deposits contrast with the background shelf sedimentation by their coarser grain size, element composition, internal structure, and erosive base, making them discernible in the sub-bottom data and cores. Especially the ca. 3600 cal yr BP deposit is exceptionally well-preserved at one of the coring sites. The clear differentiation into several sections enables further insights into offshore tsunami transport and depositional processes. This study demonstrates that the record and preservation of tsunami deposits were possible on the Algarve shelf in specific locations sheltered from possible alterations. Our findings extend the tsunami catalogs of Portugal with a previously unknown tsunami dated to ca. 3600 cal yr BP.Item Assessment of prospective geological hazards in Torrevieja-La Mata coast (western Mediterranean) based on Pleistocene and Holocene events(Natural hazards and earth system sciences, 2021) Torres, Trinidad; Ortiz, José E.; Mediavilla López, Rosa María; Sánchez-Palencia, Yolanda; Santisteban Navarro, Juan Ignacio; Vega Panizo, RogelioThe coastal zone in which the lagoons of La Mata and Torrevieja (Eastern Spain) developed can be described as a compilation of geo-hazards typical of the Mediterranean realm. This study has focused mainly on those linked to recent tectonics. Extensive use of the amino acid racemization dating method allowed us to establish the evolution of all the geomorphological units differentiated in the area, the most striking manifestation being at the La Mata Lagoon Bar, where MIS 5 deposits settled on MIS 7 sediments along a marked erosive unconformity, thereby attesting coastal uplift between these two stages. In addition, recent uplift processes were reflected on stepped abrasion platforms and, in some cases, enormous boulders were transported over these platforms by extreme surge waves. Furthermore, we obtained feasible evidence that, during the end of MIS 5, an earthquake with an offshore epicenter linked to Torrevieja Fault, Bajo Segura Fault or the set of faults linked to the former, was responsible for tsunami surge deposits represented in accumulations of randomly arranged and well-preserved Glycymeris and Acanthocardia shells. Recent catastrophic effects linked to the earthquakes were also detected. In this regard, comparison of the paleontological and taphonomic analyses allowed us to discern between wave and tsunami surge deposits. Therefore, evidence of these hazards undoubtedly points to important future (and present) erosive and/or catastrophic processes, which are enhanced by the presence of tourist resorts and salt-mining industry. Thus, these sites are also threatened by future increases in sea level in the context of warmer episodes, attested by raised marine fossil deposits. At the north of Cervera Cape, beaches will be eroded, without any possibility of sediment input from the starved Segura River delta. At the south of this cape, waves (and tsunamis) will erode the soft rocks that built up the cliff, creating deep basal notches.Item Caracterización mineralógica de los depósitos holocenos del Marjal de Almenara (Castellón-Valencia, España). Implicaciones paleoambientales(Geotemas, 2016) Moral González, Begoña del; Mediato Arribas, José Francisco; Ugarte, Ernesto; Mediavilla López, Rosa María; Santisteban Navarro, Juan IgnacioSe presenta la mineralogía de los depósitos holocenos del Marjal de Almenara, en las costas de Castellón-Valencia. Las variaciones en la composición de las asociaciones minerales y su relación con los ambientes de sedimentación permiten conocer en detalle los controles sedimentarios. Se ha realizado el estudio sobre 41 muestras procedentes de tres sondeos que están agrupadas en función de 6 facies sedimentarias. La relación entre la mineralogía y las facies muestra que el aporte de filosilicatos (illita, fundamentalmente) hacia el humedal proviene de las áreas continentales, donde predominan los depósitos aluviales (mantos de arroyada), mientras que el cuarzo procede de los depósitos marinos litorales (washover-fan). Las facies lacustres conforman un cinturón de facies que se distribuye desde más someras, arcillas y turbas, a más profundas, fangos carbonáticos y carofítas. La mineralogía de estas facies indica: que las arcillas sufren procesos post-deposicionales ligados a los periodos inundación y desecación; y que la facies de turbas, situada en la zona sublitoral detiene el aporte de terrígenos (cuarzo y filosilicatos) hacia el centro del humedal donde se ubican los fangos carbonáticos y niveles de concentración de caráceas formados principalmente por calcita.Item Pluridisciplinary analysis and multi-archive reconstruction of paleofloods: Societal demand, challenges and progress(Global and Planetary Change, 2019) Schulte, Lothar; Schillereff, Daniel; Santisteban Navarro, Juan IgnacioFloods are one of the gravest natural hazards for societies, worsened by population growth, unchecked development, and climate change. From a Global Change perspective, past extreme events merit particular interest because they can be linked to wider climate and environmental changes, introduce perturbations. During the last decade, knowledge of long-term flood frequency and magnitude has been improved by extracting data from different types of archive. But, despite advances in dating methods, proxies and statistical techniques and efforts to identify atmospheric drivers, some fundamental questions remain unresolved. The Special Issue entitled “Pluridisciplinary analysis and multi-archive reconstruction of paleofloods” in the journal Global and Planetary Change addresses these uncertainties and complexities by assembling a selection of studies, which were first presented at the Past Climate Changes (PAGES) Open Scientific Meeting held at Zaragoza in 2017. In this introductory paper, the guest editors outline the 17 research contributions and meta-data from the 17 paleoflood studies were systematically analyzed in terms of i) geographical distribution; ii) methodologies applied; iii) types of archives; iii) numbers of flood series compiled and iv) spatial and temporal resolution of paleoflood data. The data indicate that paleoflood studies focused on fluvial depositional environments show a higher rate of integration with other types of paleoflood archive (mean of 4.5 types of archive) than studies focused on documentary sources (mean of 3.5) and lake sediments (mean of 2.4). We suggest that this strategy of archive integration has been adapted to effectively compensate for the higher uncertainties of fluvial deposition in floodplains. Statistical processing of the meta-data shows quantitative associations between specific types of flood archive and offers a solid platform for designing the optimal approach for multi-archive paleoflood research. A qualitative review and visual comparison of the 17 paleoflood series shows some consistent trends and breaks but also notable differences within and between regions. While a trend of increased flooding since 4-5 ka BP is evident, the lack of synchronicity between breaks and the coeval increases and decreases in fluvial activity is manifest. The majority of studies in the Special Issue do denote the 19th century – including the youngest cool climate pulses during the Little Ice Age – as a particularly flood-rich period. It is more difficult to assess the 20th century because of social changes, population growth and extensive river modification. Despite the mentioned uncertainties, 10 of 14 papers do not record the 20th century as an exceptional flood period. Assessing the effects of human impact on paleoflood calendars and disentangling anthropogenic from natural drivers are major challenges in integrated paleoflood analysis. It is concluded that the interpretation of flood series is complex as landscapes and flood drivers are heterogeneous and systems show different sensitivities to flood control and drivers. Thus, the study of past floods, from historical and natural archives, is challenging but also offers unparalleled opportunities to document low-frequency, large-magnitude flood events, which occurred under a broad range of climate and/or environmental scenarios, and, probably, the only way to reconstruct robust paleoflood series.Item Millennial-scale cycles of aridity as a driver of human occupancy in central Spain?(Quaternary International, 2016) Santisteban Navarro, Juan Ignacio; Mediavilla, Rosa; Celis, Alberto; Castaño, Silvino; Losa, Almudena de laHuman settlements around the fluvial wetland of Las Tablas de Daimiel (central Spain) have been related to the water availability in this area for nearly 5500 years; however the relationship of the hydrology of the wetland to climate change remains uncertain. Whilst archaeological and pollen data provide contradictory arguments, statistical empirical mode decomposition of geochemical data from core S-1 reveals arid periods ca. 1.8 cal. ka BP, ca. 3.3 cal. ka BP and ca. 5.5 cal. ka BP between which periods both Bronze Age and Iberian-Roman settlements developed. These periods can be identified in other records of the Iberian Peninsula and around the western Mediterranean. Comparison of these records points to a complex spatial pattern that evolved in time and, despite a number of forcings (volcanism, solar activity, atmosphere-ocean interactions) being invoked to explain such periods, there is no clear mechanism to explain their spatial pattern and the changes that have taken place since 2.5 ka BP.Item Análisis geoquímico del registro Holoceno del Marjal de Almenara. Variaciones eustáticas(Avances de geomorfología litoral : actas de las VI Jornadas de Geomorfología Litoral, celebradas del 7 al 9 de septiembre de 2001 en Tarragona, 2011) Mediato, José F.; Mediavilla López, María Rosa; Santisteban Navarro, Juan Ignacio; Dabrio González, Cristino José; Montoya Montes, Isabel; Rodríguez Santalla, Inmaculada; Sánchez García, María JoséLa utilización conjunta del análisis secuencial y geoquímico aplicado a depósitos de lagunas costeras (marjales) es una herramienta potente para el análisis de las variaciones del nivel del mar durante los últimos milenios. La aplicación de dicha metodología en los depósitos del Marjal de Almenara (Castellón) permite identificar, las variaciones en la lámina de agua del humedal y de la intrusión salina que pueden relacionarse con variaciones relativas del nivel del mar. El estudio ha dado como resultado tres momentos de ascenso relativo del nivel del mar (ca. 5300 años BP, ca.3500 años BP y ca. 2000 años BP).Item Climate-Dependent Groundwater Discharge on Semi-Arid Inland Ephemeral Wetlands: Lessons from Holocene Sediments of Lagunas Reales in Central Spain(Water, 2020) Mediavilla López, Rosa María; Santisteban Navarro, Juan Ignacio; López Cilla, Ignacio; Galán de Frutos, Luis; Hera Portillo, África de laWetlands are environments whose water balance is highly sensitive to climate change and human action. This sensitivity has allowed us to explore the relationships between surface water and groundwater in the long term as their sediments record all these changes and go beyond the instrumental/observational period. The Lagunas Reales, in central Spain, is a semi-arid inland wetland endangered by both climate and human activity. The reconstruction of the hydroclimate and water levels from sedimentary facies, as well as the changes in the position of the surface water and groundwater via the record of their geochemical fingerprint in the sediments, has allowed us to establish a conceptual model for the response of the hydrological system (surface water and groundwater) to climate. Arid periods are characterized by low levels of the deeper saline groundwater and by a greater influence of the surface freshwater. A positive water balance during wet periods allows the discharge of the deeper saline groundwater into the wetland, causing an increase in salinity. These results contrast with the classical model where salinity increases were related to greater evaporation rates and this opens up a new way of understanding the evolution of the hydrology of wetlands and their resilience to natural and anthropogenic changes.Item Late Quaternary stratigraphy of the La Janda Basin (SW Spain) - first results and palaeoenvironmental significance(Geophysical Research Abstracts, 2017) Höbig, Nicole; Santisteban Navarro, Juan Ignacio; Mediavilla López, Rosa María; May, Simon Matthias; Klasen, Nicole; Brückner, Helmut; Van’t Hoff, Jasmijn; Reicherter, KlausThe La Janda basin in southern Spain is a near-shore geo-bio-archive comprising a variable Quaternary depositional history, with shallow marine, lacustrine, palustrine, and terrestrial strata. In the 1930s the lake was drained and is serving now as a huge agricultural area. The 33 m-core recovered in fall 2016 along with several shallower drill cores up to c. 15 m, reveals insights into a unique mixed terrestrial palaeo-environmental archive in Andalucia influenced by the Atlantic Ocean and hence the North Atlantic Oscillation (NAO) within the Gulf of Cádiz. The basin's evolution was influenced both by the postglacial marine transgression and by an active tectonic fault controlling most of the accommodation space by causing subsidence. Our long core was accompanied by further corings along an E-W striking transect in order to reveal also the relation of the influence of tectonic activity with sedimentary sequences. Multi-Sensor Core Logging has been completed. Results of sedimentological, geochemical and micropalaeontological analyses will be presented in the frame of the climate variations during the Late Pleistocene and the Holocene, along with a preliminary age-depth model based on radiocarbon (AMS-14C) and optical stimulated luminescence (OSL) dating techniques. Our investigations ultimately aim at providing valuable information on major Late Pleistocene to Holocene climatic and palaeo-environmental fluctuations in the southernmost part of the Iberian Peninsula.
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