114 research outputs found
Fusulines from the Central Asturian Coalfield (Pennsylvanian, Cantabrian Zone, Spain) and their significance for correlation.
FUSULINOIDEANS FROM THE PUENTELLÉS FORMATION (UPPER CARBONIFEROUS, NW SPAIN): DISCUSSION ON PHYLOGENY, PALEOECOLOGY AND PALEOBIOGEOGRAPHY
The Cantabrian Zone is the only area in Western Europe that contains marine successions of Kasimovian and Gzhelian (late Late Carboniferous, late Pennsylvanian) age. These successions yield fusulinoideans that are presently the subject of an in depth-study by members of a IUGS SCCS working group intending to find stratigraphic markers for the subdivision of the Carboniferous System. The youngest fusulinoidean faunas of the Cantabrian Zone are recorded in the PuentellĂ©s Formation, a succession of calcareous strata consisting of two members. The lower member is made up of reworked and re-sedimented carbonates, which form shallow turbidite deposits showing frequent lateral changes of facies, whereas the upper member corresponds to autochthonous limestones, mainly consisting of dark mudstones, skeletal wackestones and thick-bedded boundstones. Generally speaking, the lower member is late Kasimovian in age while the upper one is early Gzhelian. However, there are also a few successions of late Kasimovian age that show sedimentary facies similar to those of the upper member. The fusulinoidean assemblages from the lower member are dominated by elongated species of the genus Ferganites, which sometimes occur with Schubertella and Staffella species. Rauserites, Tumefactus, Jigulites, Quasifusulina, as well as certain Ferganites species showing obese shell, mainly appear in strata belonging to the upper member.Detailed analyses of the fusulinoideans from the Cantabrian Zone have allowed several questions related to their paleoecology, biostratigraphy, and paleobiogeography to be ascertained. First, it has been shown that the Ferganites accumulated in the strata of the lower member could have lived in near-shore and high-energy environments. The presence of some relevant forms (e. g. Rauserites cf. rossicus, and Jigulites sp.) allow a correlation between the Cantabrian successions and the standard stratigraphic units of the Russian Platform. Moreover, the composition of the fusulinoidean assemblages clearly shows the biogeographic affinities of the Cantabrian Zone with the Carnic Alps and the Central Asian regions. On the contrary, these assemblages differ greatly from those in other western Eurasian areas, such as the Russian Platform and the Donets Basin, suggesting that these areas were not well-connected with the Paleo-Tethys. Some observations give rise to relevant questions on more general aspects dealing with the latest Carboniferous fusulinoideans while yielding, at the same time, preliminary data for solving them. This is the case of the phrenotheca, an inner partition existing in some fusulinoidean shells whose functional role is still uncertain. The abundance in the Cantabrian Zone strata of Tumefactus specimens showing phrenotheca provides information for reconstructing its geometry as well as enabling speculation on its likely function. Another problematic aspect concerns the origin and distribution of the genus Triticites. It is noteworthy that this genus seems to be absent from both the Cantabrian Zone and most Eurasian areas, bringing up the question of whether the American and the Eurasian Triticites really had a common ancestor. The possibilities involved are discussed here. 
Fusulines from the Central Asturian Coalfi eld (Pennsylvanian, Cantabrian Zone, Spain) and their signifi cance for biostratigraphic correlation
3-D modelling of a fossil tufa outcrop. The example of La Peña del Manto (Soria, Spain)
[EN]Classical studies of tufas lack quantitative outcrop descriptions and facies models, and normally do not
integrate data from subsurface in the stratigraphic and evolutive analysis. This paper describes themethodology
followed to construct one of the first digital outcrop models of fossil tufas. This model incorporates
3-D lines and surfaces obtained from a terrestrial laser scanner, electric resistivity tomography
(ERT) profiles, and stratigraphic and sedimentologic data from 18 measured sections. This study has
identified seven sedimentary units (from SU-1 to SU-7) which are composed of tufa carbonates (SU-1;
3; 5; 6) and clastics (SU-2; 4; 7). Facies identified occur in different proportions: phytoherm limestones
of bryophytes represent 43% of tufa volume, bioclastic limestones 20%, phytoherm limestones of stems
12%, oncolitic limestones 8%, and clastics 15%. Three main architectural elements have been identified:
1) Steeply dipping strata dominated by phytoherm limestones of bryophytes; 2) gently dipping strata
dominated by phytoherm limestones of stems; and 3) horizontal strata dominated by bioclastic and
oncoid limestones. The alternation of tufa growth and clastic input stages is interpreted as the result of
climatic changes during Mid–Late Pleistocene.18.KA4A-463 A.C.01, Universidad de Salamanca CGL2014-54818-P of the Ministerio
de EconomĂa y Competitividad (MINECO)
Constraining the Timing and Amplitude of Early Serpukhovian Glacioeustasy With a Continuous Carbonate Record in Northern Spain
Quartz crystallite size and moganite content as indicators of the mineralogical maturity of the carboniferous chert: the case of cherts from Eastern Asturias (Spain)
Chert samples from different coastal and inland outcrops in the Eastern Asturias (Spain) were mineralogically investigated for the first time for archaeological purposes. X-ray diffraction, X-ray fluorescence, transmission electron microscopy, infrared and Raman spectroscopy and total organic carbon techniques were used. The low content of moganite, since its detection by X-ray diffraction is practically imperceptible, and the crystallite size (over 1000 Å) of the quartz in these cherts would be indicative of its maturity and could potentially be used for dating chert-tools recovered from archaeological sites. Also, this information can constitute essential data to differentiate the cherts and compare them with those used in archaeological tools. However, neither composition nor crystallite size would allow distinguishing between coastal and inland chert outcrops belonging to the same geological formations.This research was funded by the Spanish State Plan for R+D, grant number HAR2017–82557-
Jurassic rifting to post-rift subsidence analysis in the Central High Atlas and its relation to salt diapirism
The subsidence evolution of the Tethyan Moroccan Atlas Basin, presently inverted as the Central High Atlas, is characterized by an Early Jurassic rifting episode, synchronous with salt diapirism of the Triassic evaporite-bearing rocks. Two contrasting regions of the rift basin - with and without salt diapirism - are examined to assess the effect of salt tectonics in the evolution of subsidence patterns and stratigraphy. The Djebel Bou Dahar platform to basin system, located in the southern margin of the Atlas Basin, shows a Lower Jurassic record of normal faulting and lacks any evidence of salt diapirism. In contrast, the Tazoult ridge and adjacent Amezra¿ı basin, located in the centre of the Atlas Basin, reveals spectacular Early Jurassic diapirism. In addition, we analyse alternative Central High Atlas post-Middle Jurassic geohistories based on new thermal and burial models (GENEX 4.0.3 software), constrained by new vitrinite reflectance data from the Amezra¿ı basin. The comparison of the new subsidence curves from the studied areas with published subsidence curves from the Moroccan Atlas, the Saharan Atlas (Algeria) and Tunisian Atlas show that fast subsidence peaks were diachronous along the strike, being younger towards the east from Early-Middle Jurassic to Late Cretaceous. This analysis also evidences a close relationship between these high subsidence rate episodes and salt diapirism
L'experiència artĂstica de la fotografia com a eina terapèutica: estimulaciĂł emocional i normalitzaciĂł de la imatge de l’Alzheimer i la vellesa
La Residència i Centre de dia Oms-Residència Sant Miquel de la Conselleria de FamĂlia i Serveis Socials acull una poblaciĂł de gent gran que tĂ© un nivell mĂ xim de dependència i molts de casos, a mĂ©s, tambĂ© tenen diagnòstic de demència en els graus moderat i avançat. Aquesta problemĂ tica, que tĂ© repercussions sociosaniĂ ries importants, precisa un abordatge integral que incideixi en tots els aspectes que estan lligats al deteriorament cognitiu, al declivi fĂsic i a alteracions conductuals associades a la patologia. Tot i que Ă©s un procĂ©s crònic, irreversible i progressiu, fins i tot a les darreres fases de la malaltia es poden aplicar diferents estratègies d’intervenciĂł que tenen resultats positius. «El gesto como terapia. FotografĂas Antonio Molina» i «De los besos no me olvido. Los enfermeros azules visitan mi colegio» sĂłn dos projectes que potencien el valor del gest i els beneficis de l’emociĂł com a eina valuosa per comprendre la solidaritat intergeneracional i la normalitzaciĂł de la imatge de la demència, i acostar-nos-hi, en una aposta per les terĂ pies no farmacològiques. A travĂ©s de l’experiència artĂstica, mitjançant la fotografia, el vĂdeo i el dibuix, hom pretĂ©n que la imatge sigui un punt de partida per investigar i fer propostes socioeducatives al voltant de la vellesa i la dependència.La Residència i Centre de dia Oms-Residència Sant Miquel de la Conselleria de FamĂlia i Serveis Socials acoge a una poblaciĂłn mayor con el máximo nivel de dependencia y con frecuencia diagnosticada de demencia en sus grados moderados y avanzados. Esta problemática, que tiene importantes repercusiones sociosanitarias, precisa de un abordaje integral que incida en todos aquellos aspectos ligados al deterioro cognitivo, declive fĂsico y alteraciones conductuales asociadas a la patologĂa. A pesar de tratarse de un proceso crĂłnico, irreversible y progresivo, incluso en las Ăşltimas fases de la enfermedad se pueden llevar a cabo diferentes estrategias de intervenciĂłn con resultados positivos. «El gesto como terapia. FotografĂas Antonio Molina» y «De los besos no me olvido. Los enfermeros azules visitan mi colegio» son dos proyectos que potencian el valor del gesto, y los beneficios de la emociĂłn como herramienta valiosa para la comprensiĂłn y el acercamiento, en una apuesta por las terapias no farmacolĂłgicas, la solidaridad intergeneracional y la normalizaciĂłn de la imagen de la demencia. A travĂ©s de la experiencia artĂstica, mediante la fotografĂa, el video y el dibujo se persigue hacer de la imagen un punto de partida para la investigaciĂłn y para propuestas socioeducativas en torno a la vejez y la dependencia
FADS2 Function Loss at the Cancer Hotspot 11q13 Locus Diverts Lipid Signaling Precursor Synthesis to Unusual Eicosanoid Fatty Acids
Background: Genes coding for the fatty acid desaturases (FADS1, 2, 3) localized at the cancer genomic hotspot 11q13 locus are required for the biosynthesis of 20 carbon polyunsaturated fatty acids (PUFA) that are direct eicosanoid precursors. In several cancer cell lines, FADS2 encoded D6 and D8 desaturation is not functional. Methodology/Principal Findings: Analyzing MCF7 cell fatty acids with detailed structural mass spectrometry, we show that in the absence of FADS2 activity, the FADS1 product D5-desaturase operates to produce 5,11,14–20:3 and 5,11,14,17–20:4. These PUFA are missing the 8–9 double bond of the eicosanoid signaling precursors arachidonic acid (5,8,11,14–20:4) and eicosapentaenoic acid (5,8,11,14,17–20:5). Heterologous expression of FADS2 restores D6 and D8-desaturase activity and normal eicosanoid precursor synthesis. Conclusions/Significance: The loss of FADS2-encoded activities in cancer cells shuts down normal PUFA biosynthesis, deleting the endogenous supply of eicosanoid and downstream docosanoid precursors, and replacing them with unusual butylene-interrupted fatty acids. If recapitulated in vivo, the normal eicosanoid and docosanoid cell signaling milieu would be depleted and altered due to reduction and substitution of normal substrates with unusual substrates, with unpredictable consequences for cellular communication
A multi-method approach for speleogenetic research on alpine karst caves. Torca La Texa shaft, Picos de Europa (Spain)
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