1,565 research outputs found

    Hydrological influences on long-term gas flow trends at locations in the Vogtland/NW Bohemian seismic region (German-Czech border)

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    One of the typical methods for the identification of seismo-hydrological effects is to monitor changes in the free gas flow throughout springs or mofettes. For several years, the gas flow regime of mineral springs at Bad Brambach (Germany) and mofettes in the Nature Park Soos (Czech Republic) and its dependence on hydro-/meteorological parameters have been studied. The mineral spring ‘Wettinquelle’, Bad Brambach, is a well-known seismo- hydrologically sensitive location for swarmquakes at a special epicentral area of NW Bohemia. Since 2000, a slight upward trend in the gas flow of three Bad Brambach mineral springs has been observed, which became stronger after the ‘Eisenquelle’ spring capture reconstruction (winter 2003/2004). Similar behaviour could be detected at a mofette in Soos. The results correspond to a 3He/4He mantle ratio increase in gases at mofettes in the Cheb Basin (CZ) traced by other authors for more than 12 years, and could give hints for a higher degassing activity of the magma body below that area. Common and special properties in the degassing regimes of the Bad Brambach and Soos locations are discussed. It is demonstrated that the long-term gas flow trend was interrupted in 2003 because of very low groundwater levels. This effect was amplified by the artificial groundwater lowering during the ‘Eisenquelle’ spring capture reconstruction

    Physiological changes occurring in plant tissue as a result of stimuli administered to break the rest period

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    "Approved, W.L. Howard."Typescript.Phographs and charts pasted in.It is a matter of common knowledge that most of our woody plants do not grow continuously throughout the year. The fact is brought to our attention especially in spring, when we may observe the awakening of the vegetation which has been dormant for some time. After the buds open, leaves and twigs continue to grow rather rapidly. Sooner or later, however, vegetative activity diminishes and finally ceases when the terminal buds are formed. The plants are gradually preparing to go into their rest period. What causes this annual suspension of growth? Is it due simply to the lack of suitable external growth conditions? Since the rest period of most of the woody plants happens to fall during winter when temperature and other factors are unfavorable for growth, we are liable to be led to believe that the annual rest is caused simply by external influences. If there is such a simple relation as this between winter and the occurrence of the rest period, then we should not expect plants to suspend vegetative activity if growth conditions remained favorable through the year.Includes bibliographical reference

    VARIAZIONI NEL FLUSSO DI CO2 OSSERVATE NEL MARZO-APRILE 2009 IN ITALIA CENTRALE

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    In tutto il mondo nelle aree di collisione tettonica è stata osservata la presenza di sorgenti di acque calde o di gas di origine endogena (Italiano et al., 2001 e riferimenti citati). Il gas emesso più importante sotto il profilo quantitativo è l’anidride carbonica il cui ruolo è stato spesso sottolineato per giustificare la generazione di anomalìe di carattere geochimico osservate nelle acque sotterranee o nelle emissioni gassose. Nell’Italia centro-meridionale esistono numerose emissioni spontanee di anidride carbonica note come mofete o mefite. Nel corso della sequenza sismica del 1997 verificatasi in Umbria-Marche sono state monitorate le caratteristiche fisiche e composizionali di alcune emissioni di CO2 presenti nel territorio interessato dai principali eventi di carattere tettonico (Martinelli e Albarello, 1997). In particolare nel corso del 1997 sono state osservate variazioni di flusso di gas totale nelle emissioni di Monte Castello di Vibio, Umbertide e Massa Martana. Nelle stesse aree sono state osservate variazioni significative di carattere composizionale in grado di confermare la non stazionarietà dell’origine dei gas emessi (Italiano et al., 2004; Italiano et al., 2009 e bibliografia citata). Nel Comune di Massa Martana è localizzata l’emissione spontanea di anidride carbonica di San Faustino. L’emissione principale è captata da una opera di presa composta da una stanza sotterranea e da un insieme di tubi che convogliano il gas verso l’esterno. Alla fine del percorso di tubi è stata installata una strumentazione in grado di misurare la portata del gas. Il sensore è del tipo a “filo caldo”. Altri parametri di carattere ambientale sono monitorati nel sito e nella zona. Nel periodo 2005-2008 sono state osservate variazioni nei valori di portata del gas emesso in parte probabilmente ascrivibili alla attività tettonica della zona. Nel corso del 2009 sono stati affrontati e risolti problemi tecnici di alimentazione elettrica, ripristinata nel corso del mese di marzo. Alla fine del mese di Marzo 2009 e nel mese di aprile 2009 i valori di portata registrati sono stati pari a circa il doppio della normalità. I valori di portata sono poi ridiscesi entro la normalità entro un mese dalla data dell’evento principale della sequenza sismica del 2009 che ha interessato vaste aree dell’Abruzzo. La distanza tra il sito di osservazione e l’area epicentrale dell’evento principale della sequenza simica dell’aprile 2009 è di circa 80 km. Nella letteratura scientifica sono state riportateanomalìe di carattere geofisico e geochimico rilevate a distanze paragonabili a quelle descritte in concomitanza con eventi simici significativi. Fenomeni di possibile degassamento terrestre sono stati rilevati in quasi contemporaneità da altre unità di ricerca in grado di monitorare fenomenologie di area vasta con l’ausilio di tecniche satellitari (Aliano et al., 2009; Tramutoli et al., 2009). Il fenomeno osservato è iniziato alcuni giorni prima dell’evento sismico (Mw=6.3) del 6 aprile 2009 e può essere, in principio, interpretato come esito di processi di deformazione crostale osservati da altre unità di ricerca (e.g. Caporali, 2009). La composizione chimica di gas campionati nell’area epicentrale indica l’esistenza di fenomeni di fratturazione profonda e di liberazione di anidride carbonica di origine non superficiale (Bonfanti et al., 2009 e bibliografia citata, Italiano et al., 2009). La generazione e liberazione di gas di origine profonda è, in principio, in grado di confermare l’esistenza di possibili ulteriori anomalìe osservate nei fluidi della zona (e.g. Plastino et al., 2009). Il fenomeno osservato potrebbe essere interpretato come un fenomeno precursore dell’evento principale registrato e analizzato a posteriori. La possibile applicabilità del fenomeno osservato come strumento utile per migliorare le valutazioni di hazard è discussa e commentata

    The Einstein 3-form G_a and its equivalent 1-form L_a in Riemann-Cartan space

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    The definition of the Einstein 3-form G_a is motivated by means of the contracted 2nd Bianchi identity. This definition involves at first the complete curvature 2-form. The 1-form L_a is defined via G_a = L^b \wedge #(o_b \wedge o_a). Here # denotes the Hodge-star, o_a the coframe, and \wedge the exterior product. The L_a is equivalent to the Einstein 3-form and represents a certain contraction of the curvature 2-form. A variational formula of Salgado on quadratic invariants of the L_a 1-form is discussed, generalized, and put into proper perspective.Comment: LaTeX, 13 Pages. To appear in Gen. Rel. Gra

    Einstein-aether theory, violation of Lorentz invariance, and metric-affine gravity

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    We show that the Einstein-aether theory of Jacobson and Mattingly (J&M) can be understood in the framework of the metric-affine (gauge theory of) gravity (MAG). We achieve this by relating the aether vector field of J&M to certain post-Riemannian nonmetricity pieces contained in an independent linear connection of spacetime. Then, for the aether, a corresponding geometrical curvature-square Lagrangian with a massive piece can be formulated straightforwardly. We find an exact spherically symmetric solution of our model.Comment: Revtex4, 38 pages, 1 figur

    Anomalous fluid emission of a deep borehole in a seismically active area of Northern Apennines (Italy)

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    The Miano borehole, 1047 m deep, is located close to the river Parma in the Northern Apennines, Italy. A measuring station has been installed to observe the discharge of fluids continuously since November 2004. The upwelling fluid of this artesian well is a mixture of thermal water and CH4 as main components. In non-seismogenic areas, a relatively constant fluid emission would be expected, perhaps overlaid with long term variations from that kind of deep reservoir over time. However, the continuous record of the fluid emission, in particular the water discharge, the gas flow rate and the water temperature, show periods of stable values interrupted by anomalous periods of fluctuations in the recorded parameters. The anomalous variations of these parameters are of low amplitude in comparison to the total values but significant in their long-term trend. Meteorological effects due to rain and barometric pressure were not detected in recorded data probably due to reservoir depth and relatively high reservoir overpressure. Influences due to the ambient temperature after the discharge were evaluated by statistical analysis. Our results suggest that recorded changes in fluid emission parameters can be interpreted as a mixing process of different fluid components at depth by variations in pore pressure as a result of seismogenic stress variation. Local seismicity was analyzed in comparison to the fluid physico-chemical data. The analysis supports the idea that an influence on fluid transport conditions due to geodynamic processes exists. Water temperature data show frequent anomalies probably connected with possible precursory phenomena of local seismic events

    The precursor effects in the mineral spring 'Radonquelle', Bad Brambach prior to the January 14-19, 1997 earthquake swarm near Novy Kostel (NW Bohemia)

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    The main result of the 7 years’ continuous radon recording at the mineral spring “Radonquelle”, Bad Brambach was the identification of a “sensitive” epicentral area 12 km E of the measuring site (Heinicke et al., 1995a, b; Koch and Heinicke, 1996). The derived model conception is based upon a fluidal connection (water, mantle-originated gases) between the hypocenters and the observed spring, and a spreading of seismotectonically induced pressure pulse within the fluidal system. From January 6 to January 20, 1997 a radon anomaly with a maximum on January 12 was recorded at the “Radonquelle”. About 55 hours after that maximum an earthquake swarm with more than 100 single events occurred. The epicenter was located again within the above-mentioned sensitive region near Novy Kostel (Czech Republic). An increased gas flow in the spring capture was proved to be responsible for the generation of that anomaly, and confirmed the significance of the pressure pulse model

    How should the respiration rate be counted in cattle?

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    Respiration rate (RR) is a proficient indicator to measure the health status of cattle. The common method of measurement is to count the number of respiratory cycles each minute based on flank movements. However, there is no consistent method of execution. In previous studies, various methods have been described, including counting flank movements for 15 s, 30 s or 60 s as well as stopping the time for 5 or 10 breaths. We assume that the accuracy of the aforementioned methods differs. Therefore, we compared their precision with an RR sensor, which was used as the reference method in this study. Five scientists from the fields of agricultural science and veterinary medicine quantified the flank movement according to each of the five methods mentioned above. The results showed that with an average RR of 30 breaths per minute (bpm), all methods showed a high correlation to the values of the RR sensor. However, counting breaths for 60 s had the highest level of conformity with the RR sensor (Lin`s concordance correlation coefficient: 0.96) regardless of the level of RR. With rising RR, the inaccuracy increased significantly for the other four investigated methods, especially when counting 5 and 10 breaths. Therefore, we would recommend that counting for 60 s should be used as the standard method for future studies due to its high precision regardless of the level of RR

    Investigating correlations of local seismicty with anomalous geoelectrical, hydrogeological and geochemical signals jointly recorded in Basilicata Region (Southern Italy)

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    This paper presents the preliminary results analysing the correlation between local seismicity and geoelectrical, hydrogeological and geochemical signals concomitantly recorded in Basilicata Region, one of the most seismically active areas in Southern Italy. The signals were recorded by two stations: Tito and Tramutola. Tito station measures vertically the Self-Potential field (SP) by an array of five no-polarizable electrodes equally spaced with the common electrode at 20 m depth as well as water-level, water-temperature and electrical-conductivity. Tramutola station measures self-potential signals in soil surface, gas flow and water temperature in a thermal-water well, as well as atmospheric barometric pressure and ambient temperature. Correlations were found between the sharp variability of the signals recorded by both stations and the seismic sequence that occurred on September 3 to 4, 2004, allowing us to link these anomalies with the tectonic evolution of the investigated area

    Anomalous fluid emission of a deep borehole in a seismically active area of Northern Apennines (Italy)

    Get PDF
    The Miano borehole of 1047 m depth is located close to the river Parma in the Northern Apennines, Italy. A measuring station is installed to observe the discharge of fluids continuously since November 2004. The upwelling fluid of this artesian well is a mixture of thermal water and methane as main components. In non-seismogenic areas, we would expect a relative constant fluid emission perhaps overlaid with long term variations from that kind of deep reservoirs during the time. However, the continuously record of the fluid emission, in particular the water discharge, the gas flow rate and the water temperature, show periods of stable values interrupted by anomalous periods of fluctuations in the recorded parameters. The anomalous variations of these parameters are of low amplitude in comparison to the total values but significant in their long-term trend. Meteorological influences of rain and barometric pressure were not detected in recorded data probably due to reservoir depth and relatively high reservoir overpressure. Influences due to the ambient temperature after the discharge were evaluated by statistical analysis. We consider that recorded changes in fluid emission parameters can be interpreted as a mixing process of different fluid components in depth by variations in pore pressure as result of seismogenic stress variation. Local seismicity was analyzed in comparison to fluid’s physico-chemical data. The analysis supports the idea of an influence to fluid transport conditions due to geodynamic processes exist. Water temperature data show frequent anomalies probably connected with possible precursory phenomena of local seismic events
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