Experimental early crystallization of K-feldspar in granitic systems : implications on the origin of magmatic fabrics in granitic rocks

One of the most outstanding characteristics of some granodioritic to granitic rocks is the presence of K-feldspar megacrysts. For instance, granodiorites and monzogranites of the Spanish Central System batholith present variable amounts of large (up to 10cm in length) euhedral K-feldspar crystals. The porphyritic textures, the euhedral shape, the alignment of plagioclase and biotite inclusions and the magmatic fabrics point to a magmatic origin for these megacrysts. This work presents a phase equilibria study in a high-K2O granodioritic system. A series of experiments were conducted with a granodioritic composition (GEMbiot) to study the crystallization sequence at the emplacement conditions in the Gredos massif, i.e. 4 H2O wt.% and 0.4GPa. Experimental results show that orthopiroxene is the liquidus phase at 1010ºC, which reacts with the H2O-rich melt to stabilize biotite between 980 and 940ºC. Plagioclase crystallizes at around 910ºC, and K-feldspar crystallizes in the matrix between 750 and 700ºC when the crystal fraction is around 0.5. However, at 850ºC, a pelite-doped experiment shows euhedral K-feldspar (≈5vol%) in both the reactive xenolith domain together with cordierite and the granodioritic domain, where the K2O wt.% rose from 4.5 in the normal experiment to 5.9 in the doped experiment. These results suggest that the bulk-assimilation process promotes the bulk and heterogeneous K2O enrichment in a huge granodioritic magma volume, which triggers an early crystallization of K-feldspar megacrysts. Because of this early crystallization of the megacrysts, the magmatic foliations defined by K-feldspar megacrysts are formed during and after the emplacement processes and are highly influenced by tectonic kinematics

Structure of the medium formed in heavy ion collisions

We investigate the structure of the medium formed in heavy ion collisions using three different models: the Color String Percolation Model (CSPM), the Core-Shell-Color String Percolation Model (CSCSPM), and the Color Glass Condensate (CGC) framework. We analyze the radial distribution function of the transverse representation of color flux tubes in each model to determine the medium's structure. Our results indicate that the CSPM behaves as an ideal gas, while the CSCSPM exhibits a structural phase transition from a gas-like to a liquid-like structure. Additionally, our analysis of the CGC framework suggests that it produces systems that behave like interacting gases for AuAu central collisions at RHIC energies and liquid-like structures for PbPb central collisions at LHC energies.Comment: 15 pages, 8 figure

Eruption dynamics of the 22–23 April 2015 calbuco volcano (Southern Chile): Analyses of tephra fall deposits

After 54 years since its last major eruption in 1961, Calbuco Volcano (Ensenada, Southern Chile) reawakened with few hours of warning on 22 April 2015 at 18:05 local time. The main explosive eruption consisted of two eruption pulses (lasting ~1.5 and 6 h each one) on 22 and 23 April, producing stratospheric (>15 km height) eruption columns. The erupted materials correspond to porphyritic basaltic andesite (~55 wt.% of SiO2). The tephra fall affected mainly the area northeast of the volcano and the finest ash was deposited over Southern Chile and Patagonia Argentina. We studied the tephra fall deposits of both pulses in terms of stratigraphy, distribution, volume, emplacement dynamics and eruption source parameters. Here, we show field observations that have been made 5-470 km downwind and distinguish five layers (Layers A, B, B1, C and D) representing different stages of the eruption evolution: eruption onset (Layer A; pulse 1), followed by the first paroxysmal event (Layer B; pulse 1), in some places interbedded by layer B1, tentatively representing the sedimentation of a secondary plume during the end of pulse 1. We recognized a second paroxysm (Layer C; pulse 2) followed by the waning of the eruption (Layer D; pulse 2). The total calculated bulk tephra fall deposit volume is 0.27 ± 0.007 km3 (0.11-0.13 km3 dense rock equivalent), 38% of which was erupted during the first phase and 62% during the second pulse. This eruption was a magnitude 4.45 event (VEI 4 eruption) of subPlinian type.Fil: Romero, J. E.. Universidad de Atacama; ChileFil: Morgavi, D.. Università di Perugia; ItaliaFil: Arzilli, F.. University of Manchester; Reino UnidoFil: Daga, Romina Betiana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Caselli, Alberto Tomás. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Negro; ArgentinaFil: Reckziegel, Florencia Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: Viramonte, Jose German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: Díaz Alvarado, J.. Universidad de Atacama; ChileFil: Polacci, M.. University of Manchester; Reino UnidoFil: Burton, M.. University of Manchester; Reino UnidoFil: Perugini, D.. Università di Perugia; Itali

Las alternativas ciudadanas emergentes en Jalisco

El documento hace una descricpión, clasificación temática y análisis de las alternativas o iniciativas ciudadanas localizadas en el estado de Jalisco, México. Los proyectos impulsados por iniciativas ciudadanas tienen como propósito la sustentabilidad, el desarrollo económico y social, la artiuclación del tejido social, la eficiencia y redefinición de las instituciones públicas, la reforma del pensamiento y la educación, y los proyectos alternativos integrales. El análisis que se hace sobre esos proyectos se centra en el perfíl de sus participantes, las relaciones o articulación que se dan entre esas iniciativas y la manera como se relacionan con las instituciones públicas.ITESO, A.C

Producción de hortalizas en invernadero

Resumen de conferenciaEl objetivo de esta investigación fue colaborar en la optimización de la producción de hortalizas en invernadero. Para ello, se establecieron diversos ensayos en el invernadero de la Estación Experimental Fabio Baudrit, Costa Rica. Se evaluaron diferentes genotipos, tipos de poda, densidades de siembra, y uso de bioactivadores. En pepino, se evaluó el rendimiento comercial (entre 137,70 y 211,90 t/ha), la longitud del fruto (entre 17,82 y 35,77 cm), y el peso del fruto (entre 215,75 y 478,33 g). En melón, se evaluó el rendimiento total (entre 0 y 70,85 t/ha; y entre 0 y 4,75 frutos/planta), el peso del fruto (entre 268,7 y 1279,4 g); y el porcentaje de sólidos solubles (entre 9,9 y 17,1 °Brix). En melón cantaloupe, el mayor rendimiento se obtuvo a la mayor densidad (3,9 plantas/m2) y en plantas sin poda, pero en melón honey dew no hubo diferencias entre los diferentes tratamientos de poda y densidad. La aplicación de bioactivadores aplicados al sustrato y el raleo de frutos no aumentaron el rendimiento o calidad del melón. En tomate, se evaluó el rendimiento total (entre 6,06 y 83,73 t/ha), el peso del fruto (entre 4,0 y 235,3 g), y el porcentaje de sólidos solubles (entre 3,6 y 11,6 °Brix). En pimiento, se evaluó el rendimiento comercial (entre 44,29 y 78,35 t/ha, y entre 10,01 y 29,25 frutos/planta), y el peso del fruto de primera calidad (entre 106,65 y 243,45 g). En berenjena, se evaluó el rendimiento comercial (entre 35,80 y 49,64 t/ha, y entre 12,25 y 15,89 frutos/planta). Se obtuvo mayor rendimiento comercial con la mayor densidad (1,3 plantas/m2).Universidad de Costa Rica/[]/UCR/Costa RicaFundación para el Fomento y Promoción de la Investigación y Transferencia de Tecnología Agropecuaria de Costa Rica/[]/FITTACORI/Costa RicaConsejo Nacional de Rectores/[]/CONARE/Costa RicaConsejo Superior Universitario Centroamericano/[]/CSUCA/GuatemalaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Estación Experimental Agrícola Fabio Baudrit Moreno (EEAFBM

The Palaeocene Cerro Munro tonalite intrusion (Chubut Province, Argentina): A plutonic remnant of explosive volcanism?

The Cerro Munro sub-volcanic intrusion is emplaced in the back-arc (400 km from the trench) as small sub-circular tonalite-granodiorite plutons with abundant radial porphyritic dikes. U-Pb zircon SHRIMP data give an age of crystallization of 57 Ma ± 1.4 Ma. It is located to the east of the North Patagonian Batholith (NPB) that shows a protracted and episodic magmatic history from Cretaceous to Miocene time. The NPB Palaeogene episode is characterized by the lack of magmatic activity at the arc axis, as small plutonic emplacements move to the fore-arc and back-arc. This Palaeogene tectono-magmatic episode is ruled by the detachment of the Aluk plate during the Aluk-Farallon-SAM triple junction, active at that time along northern Patagonia active margin, changing the Cretaceous ?NPB orogenic? setting to a Palaeogene ?Munro transitional? tectono-magmatic setting. Near the contacts, the tonalite contains abundant enclaves of igneous appearance and variable size from several cm to dm, described as autoliths. The study of autoliths and host tonalite reveals interesting results on the processes of fractionation in a thermally zoned magma chamber. Autoliths, and in a large extent the host tonalite, represent disguised cumulates from which a hydrous silicic liquid was extracted. Barometry calculations from mineral chemistry in both autoliths and tonalites record a shallow pressure of emplacement of 0.5 kbar. Rhyolite-dacite flows and ignimbrites, surrounding the northern contact of the Cerro Munro tonalite, may represent the exsolved liquid from the plutonic cumulates. The study by cathodoluminiscence and electron backscattered diffraction techniques from a rhyolite-hosted quartz supports this protracted history of the Cerro Munro magma chamber.Facultad de Ciencias Naturales y MuseoCentro de Investigaciones GeológicasConsejo Nacional de Investigaciones Científicas y Técnica

The Palaeocene Cerro Munro tonalite intrusion (Chubut Province, Argentina): A plutonic remnant of explosive volcanism?

The Cerro Munro sub-volcanic intrusion is emplaced in the back-arc (400 km from the trench) as small sub-circular tonalite-granodiorite plutons with abundant radial porphyritic dikes. U-Pb zircon SHRIMP data give an age of crystallization of 57 Ma ± 1.4 Ma. It is located to the east of the North Patagonian Batholith (NPB) that shows a protracted and episodic magmatic history from Cretaceous to Miocene time. The NPB Palaeogene episode is characterized by the lack of magmatic activity at the arc axis, as small plutonic emplacements move to the fore-arc and back-arc. This Palaeogene tectono-magmatic episode is ruled by the detachment of the Aluk plate during the Aluk-Farallon-SAM triple junction, active at that time along northern Patagonia active margin, changing the Cretaceous ?NPB orogenic? setting to a Palaeogene ?Munro transitional? tectono-magmatic setting. Near the contacts, the tonalite contains abundant enclaves of igneous appearance and variable size from several cm to dm, described as autoliths. The study of autoliths and host tonalite reveals interesting results on the processes of fractionation in a thermally zoned magma chamber. Autoliths, and in a large extent the host tonalite, represent disguised cumulates from which a hydrous silicic liquid was extracted. Barometry calculations from mineral chemistry in both autoliths and tonalites record a shallow pressure of emplacement of 0.5 kbar. Rhyolite-dacite flows and ignimbrites, surrounding the northern contact of the Cerro Munro tonalite, may represent the exsolved liquid from the plutonic cumulates. The study by cathodoluminiscence and electron backscattered diffraction techniques from a rhyolite-hosted quartz supports this protracted history of the Cerro Munro magma chamber.Facultad de Ciencias Naturales y MuseoCentro de Investigaciones GeológicasConsejo Nacional de Investigaciones Científicas y Técnica

Estado del conocimiento del conflicto por grandes felinos y comunidades rurales en Colombia: avances y vacíos de información

Despite these actions and the large number of cases reported in the country, there is minimal knowledge about this problem in Colombia and in many cases the attacks are not documented in large part by the inefficient procedures of the entities competent. Additionally, the few published studies are consolidated within gray literature, are difficult to access or have no impact on planning or threat management. In this way, knowing the current panorama and the information gaps becomes a key piece to initiate actions that promote the preventive and corrective management of the conflict.A pesar de estas acciones y el gran número de casos reportados en el país, el conocimiento que se tiene sobre esta problemática en Colombia es mínimo y en muchos de los casos los ataques no se encuentran documentados en gran parte por los trámites ineficientes de las entidades competentes. Adicionalmente, los pocos estudios publicados están consolidados dentro de literatura gris, o son de difícil acceso o no tienen impacto sobre planificación o manejo de la amenaza. De esta manera, conocer el panorama actual y los vacíos de información se vuelve una pieza clave para iniciar acciones que promuevan el manejo preventivo y correctivo del conflicto

Factores maternos asociados a prematuridad en gestantes de un hospital público de Trujillo, Perú

Background: The risk of prematurity includes a wide variety of complications at birth, such as infectious diseases, intraventricular hemorrhage, neurosensory deficiencies, respiratory failure and involvement of other systems, as well as growth and developmental problems. Therefore, the achievement of the Millennium Development Goal of reducing child mortality depends largely on the reduction of mortality related to premature birth, making it one of the most important challenges for modern public health. Objetive: To identify maternal factors associated with prematurity. Material and Methods: A retrospective case-control study was conducted on 2000 live newborns in a public hospital in Trujillo, between 2015-2019. The groups were divided according to the criteria of gestational age. The paired maternal clinical variables were analyzed according to prematurity or term, and a bivariate and multivariate analysis was made by logistic regression adjusted for confusers. Results: It was demonstrated that the number of prenatal controls less than four during gestation, is associated to prematurity (OR 2.65; IC95%: 2.21-3.18). On the other hand, the absence of a urinary tract infection (OR 0.73; IC95%: 0.56-0.95), is associated with lower risk of prematurity. Conclusions: The number of prenatal controls is an important associated factor for preterm delivery, while the absence of a UTI may be associated with a lower rate of preterm delivery in at-risk pregnancies.Introducción: El riesgo de prematuridad abarca una amplia variedad de complicaciones al nacer, como enfermedades infecciosas, hemorragia intraventricular, deficiencias neurosensoriales, insuficiencia respiratoria y afectación de otros sistemas, así como problemas de crecimiento y desarrollo. Por tanto, la consecución del Objetivo de Desarrollo del Milenio de reducir la mortalidad infantil, depende en gran medida de la reducción de la mortalidad relacionada con el nacimiento prematuro, lo que lo convierte en uno de los desafíos más importantes para la salud pública moderna. Objetivo: Identificar los factores maternos asociados a prematuridad. Material y Métodos: Se realizó un estudio de tipo caso-control retrospectivo en 2000 recién nacidos vivos de un hospital público de Trujillo, entre el 2015-2019. Se dividieron los grupos según el criterio de edad gestacional. Se analizaron las variables clínicas maternas pareadas según prematuridad o a término, y se realizó un análisis bivariado y multivariado por regresión logística ajustada por confusores. Resultados: Se demostró que el número de controles prenatales menor a cuatro durante la gestación, está asociado a prematuridad (OR 2,65; IC95%: 2,21-3,18). Por otro lado, la ausencia de una infección del tracto urinario (OR 0,73; IC95%: 0,56-0,95), está asociado a menor riesgo de prematuridad. Conclusiones: El número de controles prenatales es un factor asociado importante para parto prematuro, mientras que la ausencia de una ITU puede estar asociada a menor tasa de partos prematuros en gestantes de riesgo

Ciudades biodiversas: mamíferos medianos de la Reserva Forestal Protectora Bosque Oriental de Bogotá D. C., Colombia

In this contribution, we present an updated list of medium-sized mammals present in the Bosque Oriental Protective Forest Reserve of Bogotá. The study area includes the Bogotá Bosque Oriental Protective Forest Reserve that is located east of the city of Bogotá D.C., and commonly known as Eastern Hills.En esta contribución, presentamos un listado actualizado de los mamíferos medianos presentes en la Reserva Forestal Protectora Bosque Oriental de Bogotá. El área de estudio comprende la Reserva Forestal Protectora Bosque Oriental de Bogotá que se localiza al oriente de la ciudad de Bogotá D.C., y comúnmente conocida como Cerros Orientales