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GEO3BCN at EGU 2024

The 2024 edition of the European Geosciences Union (EGU) General Assembly is just around the corner, scheduled to take place both on-site in Vienna and virtually from 14 to 21 April. Among presenters at this year's EGU General Assembly are researche... Read more

25-03-2024 News

El CSIC presenta la Conexión Geociencias para un planeta sostenible

El Consejo Superior de Investigaciones Científicas (CSIC) acogió el pasado 14 de marzo el kick off de la nueva conexión Geociencias para un planeta sostenible. Esta nueva propuesta, coordinada por Blas Valero Garcés, del Instituto Pirenaico de Ecolog... Read more

18-03-2024 News

The paleomagnetism laboratory is involved in obtaining the first complete archaeomagnetic data from Central Asia

A study presents the first complete archaeomagnetic data of the magnetic field vector for Central Asia, a vast region that has been largely unexplored from an archaeomagnetic perspective for a long time. Bet Beamud, head of the Paleomagnetism laborat... Read more

11-03-2024 News

Ramon Carbonell, nuevo vicepresidente de la Comisión del CSIC para la Coordinación y Racionalización de las ICTS

El investigador de Geociencias Barcelona (GEO3BCN-CSIC), Ramon Carbonell, ha sido nombrado nuevo vicepresidente de la Comisión para la coordinación y Racionalización de Infraestructuras Científicas y Técnicas Singulares (ICTS) y participación en Infr... Read more

06-03-2024 News

A news study reveals that the ice flow in Greenland is younger than thought

A new international study indicates that the Northwest Greenland Ice Stream may be much younger than previously believed. The article, published in the journal Nature Communications and led by the Alfred Wegener Institute (AWI), helps to better under... Read more

22-02-2024 News

Drone view of the Amônia River and the Amazon forest. (Yurua, Ucayali, Peru). Autor: Andre Dib

Fins al 47% dels boscos amazònics podrien patir alteracions irreversibles i desaparèixer el 2050

Una nova publicació de Nature analitza els llindars potencials que podrien empènyer la selva amazònica a un punt de no retorn. L’estudi, amb participació del Consell Superior d’Investigacions Científiques (CSIC), estima que per al 2050 entre el 10% i... Read more

14-02-2024 News

Geociències Barcelona debuta a Ciència al Barri

L'alumnat del centre educatiu Front Marítim va visitar al gener els laboratoris de microscòpia i de paleomagnetisme de Geociències Barcelona (GEO3BCN-CSIC). L'activitat, realitzada en el marc de la iniciativa Ciència al Barri, va ser dirigida pels re... Read more

30-01-2024 News

El programa CSIC Cocrea impulsa proyectos de colaboración público-privada frente a los grandes retos actuales

El programa CSIC COCREA cofinancia cinco proyectos para acelerar la transición energética a partir de la producción, conversión, almacenamiento y gestión de energías limpias y sostenible. Para promover esta transición energética, los proyectos selecc... Read more

18-01-2024 News

Stephanie Barde-Cabusson gana el Concurso de Fotografía 2023

Dos imágenes de Stephanie Barde-Cabusson obtienen el primer y tercer puesto del Concurso de Fotografía 2023 organizado por Geociencias Barcelona (GEO3BCN-CSIC). Los resultados fueron presentados en la tradicional jornada de invierno del instituto, ce... Read more

21-12-2023 News

Dario Pedrazzi, guanyador de la Beca Oriol de Bolòs de Ciències Naturals 2023

L’investigador de Geociències Barcelona (GEO3BCN-CSIC), Dario Pedrazzi, és el guanyador de la Beca Oriol de Bolòs de Ciències Naturals 2023 per un estudi que porta per títol ‘Edat absoluta i caracterització vulcanològica de dos dels possibles volcans... Read more

14-12-2023 News

Mechanical properties of minerals in lunar and HED meteorites from nanoindentation testing: Implications for space mining

Peña-Asensio, E., Trigo-Rodríguez, J.M., Sort, J., Ibáñez-Insa, J. and Rimola, A. (2024), Mechanical properties of minerals in lunar and HED meteorites from nanoindentation testing: Implications for space mining. Meteorit Planet Sci. https://doi.org/10.1111/maps.14148

Latest GEO3BCN Publications

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First Full-Vector Archeomagnetic Data From Central Asia (3 BCE to 15 CE Centuries): Evidence for a Large Non-Dipole Field Contribution Around the First Century BCE

Bonilla-Alba, R., Gómez-Paccard, M., Pavón-Carrasco, F. J., Campuzano, S. A., Beamud, E., Martínez-Ferreras, V., Gurt-Esparraguera, J. M., Ariño-Gil, E., Martín-Hernández, F., & Osete, M. L. (2024). First Full-Vector Archeomagnetic Data From Central Asia (3 BCE to 15 CE Centuries): Evidence for a Large Non-Dipole Field Contribution Around the First Century BCE. Journal of Geophysical Research: Solid Earth, 129(2), e2023JB027910. https://doi.org/https://doi.org/10.1029/2023JB027910

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Thermal structure of the southern Caribbean and northwestern South America: implications for seismogenesis

Gómez-García, Á. M., González, Á., Cacace, M., Scheck-Wenderoth, M., & Monsalve, G. (2024). Thermal structure of the southern Caribbean and northwestern South America: implications for seismogenesis. Solid Earth, 15(2), 281–303. https://doi.org/10.5194/se-15-281-2024

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Critical transitions in the Amazon forest system

Flores, B. M., Montoya, E., Sakschewski, B., Nascimento, N., Staal, A., Betts, R. A., Levis, C., Lapola, D. M., Esquível-Muelbert, A., Jakovac, C., Nobre, C. A., Oliveira, R. S., Borma, L. S., Nian, D., Boers, N., Hecht, S. B., ter Steege, H., Arieira, J., Lucas, I. L., … Hirota, M. (2024). Critical transitions in the Amazon forest system. Nature, 626(7999), 555–564. https://doi.org/10.1038/s41586-023-06970-0

Latest GEO3BCN Publications

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Shear margins in upper half of Northeast Greenland Ice Stream were established two millennia ago

Jansen, D., Franke, S., Bauer, C. C., Binder, T., Dahl-Jensen, D., Eichler, J., Eisen, O., Hu, Y., Kerch, J., Llorens, M.-G., Miller, H., Neckel, N., Paden, J., de Riese, T., Sachau, T., Stoll, N., Weikusat, I., Wilhelms, F., Zhang, Y., & Bons, P. D. (2024). Shear margins in upper half of Northeast Greenland Ice Stream were established two millennia ago. Nature Communications, 15(1), 1193. https://doi.org/10.1038/s41467-024-45021-8

Latest GEO3BCN Publications

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Assessing changes in global fire regimes

Sayedi, S. S., Abbott, B. W., Vannière, B., Leys, B., Colombaroli, D., Romera, G. G., Słowiński, M., Aleman, J. C., Blarquez, O., Feurdean, A., Brown, K., Aakala, T., Alenius, T., Allen, K., Andric, M., Bergeron, Y., Biagioni, S., Bradshaw, R., Bremond, L., …, Montoya, E., Daniau, A.-L. (2024). Assessing changes in global fire regimes. Fire Ecology, 20(1), 18. https://doi.org/10.1186/s42408-023-00237-9

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Why does western Makran have a low seismicity rate?

Abbasi, M., Ghods, A., Najafi, M., Abbasy, S., Amiri, M., Shabanian, E., Kheradmandi, M., & Asgari, J. (2023). Why does western Makran have a low seismicity rate? Tectonophysics, 869, 230134. https://doi.org/10.1016/J.TECTO.2023.230134

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Polymorphism and Phase Stability of Hydrated Magnesium Carbonate Nesquehonite MgCO3·3H2O: Negative Axial Compressibility and Thermal Expansion in a Cementitious Material

Santamaría-Pérez, D., Chuliá-Jordán, R., Gonzalez-Platas, J., Otero-de-la-Roza, A., Ruiz-Fuertes, J., Pellicer-Porres, J., Oliva, R., & Popescu, C. (2024). Polymorphism and Phase Stability of Hydrated Magnesium Carbonate Nesquehonite MgCO3·3H2O: Negative Axial Compressibility and Thermal Expansion in a Cementitious Material. Crystal Growth & Design. https://doi.org/10.1021/acs.cgd.3c01171

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Impact of glacier changes and permafrost distribution on debris flows in Badswat and Shishkat catchments, Northern Pakistan

Hassan, W., Su, F., Liu, W., Hassan, J., Hassan, M., Bazai, N. A., Wang, H., Yang, Z., Ali, M., & Castellanos, D. G. (2023). Impact of glacier changes and permafrost distribution on debris flows in Badswat and Shishkat catchments, Northern Pakistan. Journal of Mountain Science, 20(12), 3687–3702. https://doi.org/10.1007/s11629-023-7894-5

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Structural style and timing of nw-se trending zagros folds in sw iran: interaction with north-south trending arabian folds and implications for petroleum geology

Vergés, J., Casini, G., Ruh, J., Cosgrove, J., Sherkati, S., Najafi, M., Casciello, E., Saura, E., Fard, I. A., Piryaei, A., de Lamotte, D. F., Letouzey, J., Goodarzi, H., Soleimany, B., & Jahani, S. (2024). STRUCTURAL STYLE AND TIMING OF NW-SE TRENDING ZAGROS FOLDS IN SW IRAN: INTERACTION WITH NORTH-SOUTH TRENDING ARABIAN FOLDS AND IMPLICATIONS FOR PETROLEUM GEOLOGY. Journal of Petroleum Geology, 47(1), 3–74. https://doi.org/https://doi.org/10.1111/jpg.12850

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The emplacement of small-volume ( less than 0,1km3) pyroclastic flow is strongly controlled by topography, according to a new study by researchers of the Institute of Earth Sciences Jaume Almera of the Spanish National Research Council (ICTJA-CSIC) and the University of Barcelona. The paper has been published in the journal Sedimentology.

The work focused on the study and characterization of the Arico ignimbrite, located in the southern slopes of the Las Cañadas volcanic complex (Tenerife, Canary Islands). These rock formations were originated by the deposition of a 670,000-year-old pyroclastic flow.

Guajara was the emission zone of this cloud, which was made up of a mix of hot gases, volcanic ashes and rock fragments. The cloud showed fast downslope movement, and was finally deposited in the valleys of the southern zone of the island, forming the studied ignimbrites.

"It is well known that pyroclastics flows are density currents controlled by the gravity and thus they tend to flow through valleys or depressed topographical zones", explains Joan Martí, researcher at ICTJA-CSIC and first author of the study. "Now, we have been able to demonstrate that, besides the slope, the emplacement of small-volume pyroclastic flows is controlled by the shape of the channel through which they flow. The bedrock morphology, obstacles, sudden slope variations or changes in the channel width are some of the topographical drivers that influence the emplacement and deposition of these types of pyroclastic flows".

20190715 FotoNoti01

To do this, the team conducted fieldwork in the Barranco de los Ovejeros where they found and described a total of 57 outcrops. In this valley, the ignimbrite deposits are well exposed. Researchers studied the lithology, stratigraphy and the sedimentological features of the ignimbrite outcrops. They also measured the slope of the previous ground, depth and width of the channels that guided the transport and the final emplacement of the flow. Researchers also took 41 samples to conduct a paleomagnetic study to estimate the emplacement temperature of the Arico ignimbrite.

According to Joan Martí, despite its age, the Arico ignimbrites is a "well-preserved and exposed deposit that permitted us to reconstruct the paleo-topography with precision. Therefore, we were able to observe how the lithological, stratigraphical and sedimentary features of the ignimbrite deposits vary on the basis of the changes of the valley's shape where they were finally emplaced".

With all the field data, researchers were able to develop a theoretical model that explains the critical mechanisms from which topography guided the emplacement of the flow.

"Besides the usual parameters that define the flow regime of this type of volcanic material current, our model includes the contour conditions imposed by a particular topography which allows establishing how the flow conditions vary along with its emplacement", notes Joan Martí.

According to the authors, this new model is "of general applicability and will help to explain other deposits of similar characteristics".

The researchers describe in their study the different features of Arico ignimbrites along 7 observation points. The paper notes that in the areas closest to the emission centre, the pyroclastic flow was efficiently channelled by the existing valleys that acted as efficient conduits. In these areas, the ignimbrite corresponds to a homogeneous moderately welded deposit.

20190715 FotoNoti03

The study also reports that in the intermediate zones, significant changes occurred in the steepness of the slope, and here, although still channelled, the flow was influenced by hydraulic jumps, which controlled the way it was emplaced. In this area, two different sedimentary units can be clearly seen in the ignimbrite: the lower unit is orange, and the upper unit is grey.

Finally, in the distal areas near the present-day coastline, where the slope is very gentle or null and without a channelling relief that provoked a radial dispersion and fast degassing of the flow, only the upper unit can be found.

The researchers say that this work allows to a better understanding of the emplacement mechanisms of ignimbrites and to improve the volcanic hazard assessment. "This study opens the door to forecast the flow regime of the small-volume pyroclastic flows as long as we know the previous topography".

Dario Pedrazzi and Domenico Doronzo, both researchers at ICTJA-CSIC, and Ferran Colombo, from the Faculty of Earth Sciences of the University of Barcelona, are the other authors of this new study.

Original article

Joan Martí et al. Topographical controls on small-volume pyroclastic flows, Sedimentology (2019). DOI: 10.1111/sed.12600

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