Littérature scientifique sur le sujet « Eruption, 1842 »

AbstractDuring the nearly 40 years covered by the study, major height differences of over ± 25 m have been revealed in the volcanic landscape of the 1970 craters in Deception Island, an active volcano in the South Shetland Islands (West Antarctica). In the last 14 years, the mean volcanic filling rate has been 1 m yr-1 and the mean erosion rate has been -0.2 m yr-1. There has been considerable landform modification mainly associated with landslide-induced accumulation, and erosion may indicate the craters’ fill over the next 30–40 years. Deception Island's eruptions have been recorded since 1842. Special attention was paid to the zones affected by the most recent volcanic events and the geomorphological changes that have taken place in those zones since then (e.g. the 1970 volcanic craters area in the last episode occurring between 1967 and 1970). Historical maps (produced before and just after the 1970 eruption) were compared with maps plotted in 1992 and updated using a 2003 image from the Quickbird satellite and data obtained with Global Navigation Satellite System technology in 2006. Techniques used included both geodetic transformation and the geometric correcting of maps.

We use new remote sensing data, historical reports, petrology and estimates of viscosity based on geochemical data to illuminate the lava emplacement flow-lines and vent structure changes of the summit ridge of Hekla during the large eruptions of 1845–46 and 1766–68. Based on the planimetric method we estimate the bulk volumes of these eruptions close to 0.4 km3 and 0.7 km3, respectively. However, comparison with volume estimates from the well-recorded 1947–48 eruption, indicates that the planimetric method appears to underestimate the lava bulk volumes by 40–60%. Hence, the true bulk volumes are more likely 0.5–0.6 km3 and 1.0–1.2 km3, respectively. Estimated melt viscosity averages for the 1766–68 eruption amount to 2.5 x10**2 Pa s (pre-eruptive) and 2.5x10**3 Pa s (degassed), and for the 1845–46 eruption 2.2x10**2 Pa s (pre-eruptive) and 1.9x10**3 Pa s (degassed). Pre-eruptive magmas are about one order of magnitude more fluid than degassed magmas. In the 1845–46 and 1947–48 eruptions, SiO2 decreased from 58–57 to 55–54 wt% agreeing with a conventional model that Hekla erupts from a large, layered magma chamber with the most evolved (silica-rich) magmas at the top. In contrast, the lava-flows from 1766–68 reveal a more complicated SiO2 trend. The lava fields emplaced in 1766 to the south have SiO2 values 54.9–56.5%, while the Hringlandahraun lava-flow that erupted from younger vents on the NE end of the Hekla ridge in March 1767 has higher SiO2 of 57.8%. This shows that the layered magma chamber model is not suitable for all lava-flows emplaced during Hekla eruptions.

For the first time, a description and timing of the development of the main external morphological characteristics of Rana arvalis Nilsson, 1842 is presented, with particular attention to the formation of skin texture. The first signs of texture in the form of dark stripes and spots appeared in tadpole skin at stages G39 – 40. At G41 – 44, the body of the tadpole acquired a typical «frog» position with an orientation of 20 – 30° to the substrate, dorsolateral stripes transformed into folds, and dark spots into tubercles in the caudo-rostral direction. At the end of metamorphosis (G45 – 46), the texture formation was completed on the entire back, and the type of morph (striata, non-striata) was easily determined. The period between the first signs of the appearance of skin texture and its complete formation took 6 – 12 days. The most stable was the interval between the primary protrusion of the forelimbs under the skin and the eruption of the first one (~12 h). The period between the eruption of the first and second forelimbs was the most variable (from an hour to three days). The results obtained highlight the plasticity and problematic nature of the phenomenon of metamorphosis in amphibians.

Abstract Lake Lau Kawar is one of the exposed areas in North Sumatra by the volcanic ash originating from Mount Sinabung eruption. The lake has been utilized as a tourism site and fish resources for consumption by the local community. Keperas (Cyclocheilichthys apogon Val. 1842) is one of the native fish commonly caught by the community. The aim of this study was to determine the levels of selected heavy metals such as copper (Cu), lead (Pb), and zinc (Zn) accumulated by C. apogon and the ones present in the lake water. The results showed that Zn present in the highest concentration followed by Cu and Pb as similar to the results from bioconcentration factor (BCF). All heavy metals (Cu, Pb, Zn) exhibited their highest concentrations in the gills, while the muscles possessed the lowest concentrations of all metals. Risk assessment based on the national and internasional standard revealed that the concentration of these metals was relatively low and safe for consumption.

AbstractFollowing the “Great Eruption” of 1843, η Carinae underwent a second major eruption around 1890. We suggest a preliminary working model developed during this meeting (in one night, hence the term “Blitz”) that attempts to explain the temporal development of the 19th century eruptions of η Car, as well as the formation of the Homunculus nebula (note that we are not offering an explanation for the cause of the Great Eruption!). The essence of the model is that after the Great Eruption ends, the star’s extended outer envelope re-adjusts itself on a thermal time scale. This re-adjustment allows envelope material to crash back onto the surface of the star, inducing the second eruption in 1890.

Drawing on a scholarly polemic of the 1930s, this paper differentiates between two ways of understanding and translating Cyprian Norwid’s formula “tatarski czyn,” as ‘Tatar deed’ (from the Polish czyn) or as ‘Tatar rank’ (from the Russian chin according to the Tsarist Table of Ranks). The aim is to show how the eruptive versus the hierarchical readings of “tatarski czyn” have influenced the opinions on Norwid’s dialogic treatise Promethidion (1851) and, more generally, on his criticism of the utopian thought of Polish Romanticism and of Russian po-litics. It was Adam Mickiewicz who in the 1820s and 1830s pointed to the homonymy between czyn and chin and its potential in enacting ambivalences between the seemingly incommensurable imaginaries of eruption and hierarchy. Moreover, Mickiewicz already linked both understandings of czyn with a stereotypical Tatar, or Mongolian, “Asianness.” In this respect, Norwid’s formula is fairly conventional. What is genuinely original, however, is how Norwid turns Mickiewicz’s earlier ideas against those of the later Mickiewicz who, in his Paris Lectures on the Slavs (1840–1844), seems to glorify the “Tatar deed.” In contrast to the “bloody ladder” of Russian bureaucracy and the irrational tendency in Mickiewicz’s activism, Norwid suggests a “gradual labor” culminating in, not erupting with, the deed (Promethidion). This aspect of Norwid’s metaphorical thought is shown in a parallel reading with the philosopher August Cieszkowski who, in his Prolegomena to Historiosophy (1838), conceptualized history as a “texture of deeds” leading to institutions. Similarly, Norwid’s positive notion of the deed, i.e. his revision of Romantic activism, should be situated beyond the alternatives of eruption and hierarchy.

On the history of mountain-related topics in Czech literature: František Palacký and Milota Zdirad PolákThe literature of the Czech national revival produced a unique type of cestopis travel account, which, from a Polish point of view, could be regarded as an equivalent of accounts of Polish Romantic travels of fellow countrymen across their country. In the Czech literature we can distinguish a clear thematic group associated with the Karkonosze mountains. It includes M.S. Patrčky’s O Krkonošských horách 1823, Josef Myslimír Ludvík’s Myslimír, po horách krkonošských putující 1824, Karel Slavoj Amerling’s Cesta na Sněžku 1832, Karel Hynek Mácha’s Pouť Krkonošská 1833–34, František Tomsa Přátelské dopisy z cesty na Sněžku 1845, Josef Frič’s Cesta přes Friedland na Krkonoše 1846, and Karel Hanuš’s Cesta na Sněžku 1847. These works testify to an expansion of themes tackled by literature during the so-called national revival. Characteristic forms of the period conformed to the Classical, pre-Romantic and Romantic conventions. One of the most interesting themes tackled by literature in those days were the mountains. In line with the spirit of national revival, the Czech cult of the domestic was expressed in the linking of the homeland and its landscape with important aspects of Czech national identity. This convention of referring, as means of self-identification, to spatial symbolism and its vocabulary was visible in the Czech and Slovak culture in several aspects. The vocabulary of Czech national symbols now included the Karkonosze mountains, Šumava or the Bohemian Forest, the Tatras and the Blanik hill. František Palacký referred to landscape-linked symbolism in his ode Na horu Radhošť, added to his youthful work, written together with Pavel Josef Šafařík, Počátkové českého básnictví obzvláště prosodie 1818. The poem formally served as an example illustrating theoretical analyses of poetry included in the study in question. Using the fact that Radhošť was a mountain in Moravia, Palacký included the mountain as a motif in a rather unique founding myth associated with the local Moravian patriotism. Thus mountains became a representative motif of the literature of the Czech national revival. When it comes to Czech poetry, mountain motifs were introduced into it on a broader scale for the first time by Milota Zdirad Polák Matěj Polák, 1788–1856 in his descriptive poem Vznešenost přírody 1819. Polák’s novelty lay in his introduction into Czech literature of a new genre, descriptive poem, as well as linguistic experiments neologisms thanks to which he developed his own poetic language. Using the category of the sublime as a tool to interpret the natural phenomena he described, Polák sought to demonstrate the richness of the forms of the world, their complexity and diversity. That is why the catalogue of motifs he used is vast. It accorded an appropriate place to the mountains with a brave attempt to concretise their motif: fragments of the poem deal with the Alps, a description of the Karkonosze mountains is highlighted and there is also a motif of volcanic eruption. Undoubtedly the most interesting and artistically the most valuable is an extensive fragment of the poem devoted to the Karkonosze mountains. The fear of the horror of high mountains, the Alps, described in the poem, found its equivalent in the writings of Jan Kollár 1793–1852, who presented his emotions associated with his stay in the Alps in an account of an 1841 journey to Italy Cestopis obsahující cestu do Horní Italie a odtud přes Tyrolsko a Bavorsko, se zvláštním ohledem na slavjanské živly roku 1841 konanou, Budin 1843. Both writers, Polák and Kollár, were hugely impressed by the mountains, but this did not lead to any Romantic reflection on their part.

Abstract We report the discovery of a previously unknown eruption of the recurrent nova M31N 2017-01e that took place on 2012 January 11. The earlier eruption was detected by Pan-STARRS and occurred 1847 days (5.06 yr) prior to the eruption on 2017 January 31 (M31N 2017-01e). The nova has now been seen to have had a total of four recorded eruptions (M31N 2012-01c, 2017-01e, 2019-09d, and 2022-03d) with a mean time between outbursts of just 929.5 ± 6.8 days (2.545 ± 0.019 yr), the second shortest recurrence time known for any nova. We also show that there is a blue variable source (〈V〉 = 20.56 ± 0.17, B − V ≃ 0.045), apparently coincident with the position of the nova, that exhibits a 14.3 days periodicity. Possible models of the system are proposed, but none are entirely satisfactory.

Abstract. Among the different meteorological hazards, droughts are those with the highest socio-economical impact on the Iberian Peninsula. Drought events have been largely studied in the instrumental period, but very little is known about the characteristics of droughts in the preinstrumental period. In this work, several series of rogation ceremonies are used to identify severe droughts within the period 1750–1850. The overlapping of the rogation series with some instrumental series served to identify some climatic characteristics of rogation ceremonies: (a) during spring, rainfall deficits needed to celebrate rogation ceremonies are smaller than in any other season; (b) the hydrological deficit in a particular region increases with the number of locations celebrating rogations simultaneously. On the other hand, it was found that between 1750–1754 and 1779–1783 are probably the driest periods of the 101 analyzed years. Both show an important number of rogations all over Iberia and during all the seasons. The most extended drought of this period occurred during the spring of 1817, affecting 15 of the 16 locations studied. This drought was influenced by the Tambora eruption (1815). The study of the climate footprint of this eruption and its comparison with similar situations in the series suggest that the spring drought of 1824 may be associated with the eruptions of the Galunggung and Usu volcanoes (1822). Further studies are required to confirm this fact and understand the atmospheric mechanisms involved.

Abstract. Among the different meteorological risks, droughts are the ones with the highest socio-economical impact in the Iberian Peninsula. Drought events have been largely studied in the instrumental period, but very little is known about the characteristics of droughts in the preinstrumental period. In this work, new series of rogation ceremonies identify severe droughts within the period 1750–1850. The overlapping of the rogation series with some instrumental series served to identify some climatic characteristics of rogation ceremonies: a) during spring, rainfall deficits needed to celebrate rogation ceremonies are smaller than in any other season; b) when the number of location celebrating rogations increases in a region the hydrological deficit on each location increases as well. On the other hand, it was found that the periods 1750–1754 and 1779–1783 are probably the driest periods of the 101 analyzed years. Both show an important number of rogations all over the Iberian Peninsula and during all the seasons. The most extended drought of this period occurred during the spring of 1817, affecting 15 of the 16 locations studied. This drought was influenced by the Tambora eruption (1815). The study of the climate footprint of this eruption and its comparison with similar situations in the series suggest that the spring drought of 1824 may be associated with the eruptions of the Galunggung and Usu volcanoes (1822). Further studies are required to confirm this fact and understand the atmospheric mechanisms involved.

The November 2004 explosive eruption of Grímsvötn volcano, Iceland (G2004) commenced as a subglacial event within the interior of the Vatnajökull ice cap before breaking through the ice cover to generate a 6-10 km high eruption column. This produced a tephra apron extending >50 km across the ice surface northwards from the eruption site, incorporating 0.047 km3 (DRE) of plagioclase-bearing, sparsely porphyritic, basaltic tephra. This study focuses on quantifying the key eruption parameters and evaluating the stratigraphy, grain size and geochemical characteristics of the proximal facies of the subaerial deposit with a level of detail and precision that has never previously been possible for a modern glacio-volcanic event. The G2004 deposit consists of a finely layered sequence which is subdivided into seven units (A-G) on the basis of differences in texture, grain size and componentry and the presence of sharp contacts between the layers. It is poorly sorted and finegrained with a median clast diameter of 1.5 Φ. The grain size characteristics and clast morphologies are indicative of intense phreatomagmatic fragmentation, despite a significant component of highly vesicular juvenile glass. A wide range in thicknesses and geometries of depositional units reflects variations in intensity and style of activity. Units C and E account for 80% of the total deposit volume, including the entire distal portion, and are interpreted to represent a mixture of (i) a widely dispersed component that fell from the upper margins of a strongly inclined (~45°) 6-10 km high plume and (ii) a locally dispersed (<3 km from source) component originating from (1) pyroclastic density currents generated by shallow explosions and tephra jets and (2) sedimentation from the jet region and lower convective column margins. The other units are only locally dispersed around the vent. A significant proportion of fine material was deposited in the near-vent region due to particle aggregation processes. The bulk of the G2004 deposit is therefore identified as the product of continuous incremental deposition during the passage of a single quasi-steady current supplied by a sustained explosive phreatomagmatic eruption, with a variable contribution of material from concurrent tephra fallout. Major oxide, trace element and volatile composition of the G2004 tephra were analysed and compared with that of the G1998 and Laki events. Results indicate that the G2004 magma originated within a shallow-level, compositionally stratified chamber and was discharged through an independent plumbing system. The parent magmas for each of these three Grímsvötn events were produced by different degrees of partial melting within a similar lower-crust or mantle source, but are not related by fractional crystallization or magma mixing. Despite episodic intense vesiculation, the G2004 magma was fragmented at very shallow levels by almost exclusively phreatomagmatic mechanisms – the effect of which was to arrest the degassing process such that only 75% of the potential magmatic sulphur budget escaped to the atmosphere.

Postglacial activity on the Askja volcanic system, north Iceland, has been dominated by basaltic volcanism. Over 80% of Askja's postglacial basalts fall within a relatively narrow compositional range containing between 4 and 8 wt.% MgO. The 'main series' is further divided into two groups separated by a distinct compositional gap evident in major and trace element concentrations. The most evolved basalts formed by fractional crystallisation within shallow magma reservoirs, followed by the extraction of residual liquid from a semi-rigid, interconnected crystal network. This process is analogous to the formation of melt segregations within single lava flows, and was responsible for generating several small-volume, aphyric basaltic lavas erupted along caldera ring fractures surrounding the Oskjuvatn (Askja lake) caldera in the early 20th century. Further examples of evolved basalt are found throughout Askja's postglacial volcanic record. However, Askja's early postglacial output is dominated by more primitive compositions. Some of the most primitive basalts erupted within the Askja caldera are found in phreatomagmatic tuff cone sequences which crop out in the walls of Oskjuvatn caldera. one such tuff sequence has been dated at between 2.9 and 3.6 ka. This tuff cone shares geochemical source characteristics, such as Nb/La and Nb/Zr, with basaltic tephras erupted during precursory activity to the Plinian-phreatoplinian eruption of 28th-29th March 1875. It may therefore be considered to be compositionally representative of the primitive basaltic magmas supplied to Askja during the postglacial period. The predominance of relatively primitive basalt (6.8 wt.% MgO) within Askia's postglacial lava succession suggests that it did not have a permanent shallow magma chamber during the postglacial period. It is envisaged that the postglacial Askja magmas evolved by a process of polybaric factionation in transient, sill-like magma storage zones located at various levels in the crust. The most primitive magmas erupted directly from deeper reservoirs, while the more evolved magmas experienced longer crustal residence times. The buoyant rise of volatile-enriched melt from these sill-like bodies, without mobilising phenocryst phases, explains the observation that almost all lavas on Askja's eastern and southern lava aprons are essentially aphyric. The 28th-29th March 1975 eruption marked the climax of a volcanotectonic episode on the Askja volanic system lasting from late 1874 to early 1876. Fissure eruptions also occurred at the Sveinagja graben, 45-65 km north of Askja, between February and October 1875, producing the Nyjahraun lava. A strong similarity exists between whole-rock major element concentrations from Myjahraun and the Askja 20th century basalts. This has led to the suggestion that these basalts originated from a common shallow magma reservoir beneath Askja central volcano, with the Nyjahraun eruptions being fed by a lateral dyke extending northwards from Askja. This theory also offers an explanation for the observation that the volume of phyolitic ejecta from 28th-29th March 1875 is significantly less than the volume of Oskjuvatn caldera, which was formed as a result of this eruption. New major and trace element data from whole-rock and glass samples indicated that Nyjahraun and the Askja 20th century basalts did not share a common parental magma. A detailed investigation of historical accounts from explorers and scientists who visited Askja between 1875 and 1932 reveals that Oskjuvatn caldera took over 40 years to reach its current form, and that its size in 1876 was equal to the volume erupted on 28th-29th March 1875. Small injections of magma into an igneous intrusion complex beneath Askja, coupled with background deflation, are sufficient to provide the required accommodation space for continued caldera collapse after 1876. Lateral flow is therefore not required to explain the volume of Oskjuvatn caldera, nor the eruption of evolved basaltic magma on the Askja volcanic system in 1875. It has been conjectured that the Holuhraun lava, located at the southern tip of the Askja volcanic system, was also connected with the 1874-76 Askja volcanotectonic episode. However, major and trace element data from whole-rock samples, glass and melt inclusions receal the Holuhraun is geochemically more similar to basalts erupted on the Bardarbunga-Veidivotn volcanic system than to postglacial basalts from Askja. The division between the 'Askja' and 'Veidivotn' geochemical signatures appears to be linked to east-west-striking lineations in the region south of Askja. This indicates that a particular geochemical signature is not necessarily confined to the tectonic expression of a single volcanic system, and has important implications for the identification and delineation of individual volcanic systems beneath the northwest sector of Vatnajokull.

Large explosive volcanic eruptions inject SO2 into the stratosphere where it is oxidised to sulphate aerosols which reflect sunlight. This causes a reduction in global temperature and precipitation lasting a few years. Here the robust features of this precipitation response are investigated, using superposed epoch analysis that combines results from multiple eruptions. The precipitation response is first analysed using the climate model HadCM3 compared to two gauge based land precipitation datasets. The analysis is then extended to a large suite of state-of-the art climate models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5). This is the first multi-model study focusing on the precipitation response to volcanoes. The large ensemble allows analysis of a short satellite based dataset which includes ocean coverage. Finally the response of major world rivers to eruptions is examined using historical records. Whilst previous studies focus on the response of just a few rivers or global discharge to single eruptions, here the response of 50 major world rivers is averaged across multiple eruptions. Results are applicable in predicting the precipitation response to future eruptions and to geoengineering schemes that seek to counteract global warming through reducing incoming solar radiation. The main model-simulated features of the precipitation response include a significant global drying over both land and ocean, which is dominated by the wet tropical regions, whilst the dry tropical ocean regions get significantly wetter following eruptions. Monsoon rainfall decreases, whilst in response to individual eruptions the Intertropical Convergence Zone shifts away from the hemisphere with the greater concentration of volcanic aerosols. The ocean precipitation response is longer lived than that over land and correlates with near surface air temperature, whilst the land response correlates with aerosol optical depth and a reduction in land-ocean temperature gradient Many of these modelled features are also seen in observational data, including the decrease in global mean and wet tropical regions precipitation over land and the increase of precipitation over dry tropical ocean regions, all of which are significant in the boreal cold season. The land precipitation response features were robust to choice of dataset. Removing the influence of the El Nino Southern Oscillation (ENSO) reduces the magnitude of the volcanic response, as several recent eruptions coincided with El Nino events. However, results generally remain significant after subtraction of ENSO, at least in the cold season. Over ocean, observed results only match model expectations in the cold season, whilst data are noisy in the warm season. Results are too noisy in both seasons to confirm whether a long ocean precipitation response occurs. Spatial patterns of precipitation response agree well between observational datasets, including a decrease in precipitation over most monsoon regions. A positive North Atlantic Oscillation-like precipitation response can be seen in all datasets in boreal winter, but this is not captured by the models. A detection analysis is performed that builds on previous detection studies by focusing specifically on the influence of volcanoes. The influence of volcanism on precipitation is detectable using all three observational datasets in boreal winter, including for the first time in a dataset with ocean coverage, and marginally detectable in summer. However, the models underestimate the size of the winter response, with the discrepancy originating in the wet tropics. Finally, the number of major rivers that undergo a significant change in discharge following eruptions is slightly higher than expected by chance, including decreased flow in the Amazon, Congo, Nile, Orange, Ob and Yenisey. This proportion increases when only large or less humanly influenced basins are considered. Results are clearer when neighbouring basins are combined that undergo the same sign of CMIP5 simulated precipitation response. In this way a significant reduction in flow is detected for northern South American, central African and less robustly for high-latitude Asian rivers, along with a significant increase for southern South American and SW North American rivers, as expected from the model simulated precipitation response.

Iceland straddles the Mid-Atlantic Ridge and overlies a mantle hotspot. This tectonic setting produces voluminous tholeiitic magmas. Volcanism in Iceland is focussed along three neovolcanic spreading ridges. During the Holocene, the Eastern Volcanic Zone (EVZ) in southeast Iceland has been the most volcanically active and has been the site of several large (>6 km3) eruptions, including the only floodbasalt type eruption in recorded history, the 1783-84 Laki eruption. Three eruptions of large volume have been sampled for this study: the 1783-84 Laki eruption (15.1 km3); the 3,000-4,000 yBP Thjórsárdalur eruption (probably >4 km3); and the ~8,600 yBP Thjórsá eruption (>21 km3). The products of these eruptions have been analysed using a range of analytical techniques, with the specific aim of investigating crystallisation, degassing and mixing processes in the magma reservoirs that feed large eruptions. The Laki eruption has been the particular focus of this study. Samples from different parts of the lava flow show fine-scale variations in trace element concentrations and ratios. This compositional variation is not fully explained by fractional crystallisation processes, but is strongly controlled by crystal accumulation as whole-rock incompatible trace element concentrations show a linear, negative correlation with the mass fraction of crystals in the sample. Simple crystal accumulation models, however, fail to explain the compositional variation, and one explanation is that the homogeneous Laki melt mixed with varying proportions of a crystal mush that contained its own liquid. The results of thermobarometry calculations indicate that the erupted Laki liquid was in equilibrium with olivine, plagioclase and augite at 1-3 kb. Most of the crystals carried by the flow are too primitive to have crystallised from the erupted liquid and barometry calculations indicate that clinopyroxene crystallised at 3-7 kb. The majority of the large crystals hosted in the Laki basalt samples are therefore antecrysts that grew within the same magma plumbing system as the Laki carrier melt but are not in direct chemical equilibrium with it. This finding is verified by the fact that olivine crystals that are too magnesian to be in chemical equilibrium with the Laki whole-rock composition contain melt inclusions with average La/Yb values that are the same within error as the whole-rock values. The wide range of La/Yb values in melt inclusions hosted in the most magnesian (Fo86) olivine crystals in comparison to the least magnesian (Fo<74) indicates the initial variability of the Laki magma prior to concurrent crystallisation and extensive mixing, which acted to homogenise the carrier melt composition. The preservation of a wide range of La/Yb within the melt inclusions in comparison to the whole-rock composition, and a range of La/Yb values in different inclusions from the same crystal, indicates short timescales between melt inclusion entrapment and quenching during eruption. Melt inclusion studies also reveal the dissolved volatile content of the Laki magma at the onset of olivine crystallisation, although the majority of H2O concentrations have almost certainly been reset by low pressure diffusive exchange with the host crystal or surrounding magma. Comparison of the behaviour of volatiles with that of incompatible elements in the melt inclusions indicates that CO2 was degassing during olivine crystallisation, but S, F and Cl were not. New estimates of total volatile loading to the atmosphere during the eruption based on melt inclusion volatile concentrations show SO2 and HCl loading comparable to previous estimates, but higher HF loading. Mass balance calculations show that the observed H2O and CO2 concentrations of melt inclusions hosted in olivines in chemical equilibrium with the Laki whole-rock composition are ~50% and ~93% lower respectively than would be expected if no pre-eruptive degassing of the magma reservoir had occurred, meaning that pre-eruptive degassing of H2O and CO2 from the magma must have been significant. Lava flows from Thjórsá are more compositionally variable than those from Laki, and have different average major and trace element compositions. Compositional variation within the Thjórsá whole-rock composition is explained by a combination of source variation and fractional crystallisation, and, unlike Laki, is not strongly controlled by crystal accumulation.

This chapter gives a historical account of three inscriptions written by Dave the Potter in 1857, tying them contextually to significant incidents of that year in Edgefield, South Carolina: the eventful funeral proceedings of Preston Brooks, a violent South Carolinian politician, and the Dred Scott decision of March 1857. Foreman’s reading of the inscription “A pretty little Girl” moves beyond previously noted allusions to Mount Vesuvius’s eruption. The essay considers the inscription in relation to Frederick Douglass’s “Slumbering Volcanoes” speech of 1849, while developing an argument for reading the inscriptions, where appropriate, as being part of a series or triptych.

Abstract After the Dorr debacle of 1842, Whig and Democratic rivalries stayed rough but nonriotous. This owed something to the withering away of issues of a deeply divisive sort. After 1840, the major problems of earlier debate, the tariff and the bank, faded. James K. Polk put to sleep the tariff issue after the long quiet ushered in by Henry Clay’s compromise of 1833, and the national bank died as surely as the president from William Henry Harrison’s sudden postinaugural illness. The last legislative legacy of the 1835 anti-abolition eruption, the gag rule, disappeared as even the most belligerent Southerners tired of giving John Quincy Adams another chance to bait them. The clearest ideological difference between the parties-the Jacksonian stress on government inactivity and the Whig insistence that government had some responsibility for promoting the general welfare-developed no policy correlatives at the national level, nor did the different rhetorical emphases on legalism, racism, and proslavery. Only when relative political outsiders brought into politics volatile issues with profounder social roots did political violence return. Religion and immigration gave the best-known incentive to new parties tied to violence, but such tumult became worst and most dangerous when integrated with the explosive question of slavery.

The eruption of Civil War led activists who had pursued distinct strategies to coalesce around support for emancipation and aid to escaped slaves. Rochester’s competing networks of women abolitionists worked together to support the labors of Harriet Jacobs and Julia Wilbur in the contraband camps of Alexandria, Virginia. With the Post children grown, former household workers and widowed friends filled the Post home; and family and fellow activists visited regularly. The outbreak of war ignited intense debates among Progressive Friends, in which Amy participated. None of the Post sons enlisted. In 1863, Amy worked with the Women’s Loyal National League, which petitioned Congress to emancipate all slaves. That December, she visited Jacobs and Wilbur in Alexandria, writing Isaac of the horrible conditions there. After the war, the Posts worked with Truth to assist newly-freed blacks. When suffragists divided over the Fifteenth Amendment, Post insisted on universal suffrage but refused to join either newly-formed women’s suffrage organization. Consumed with caring for sick relatives in the early 1870s, she was devastated when Isaac died in May 1872. By November, however, she rallied to join dozens of women trying to register and vote in Rochester.

Abstract Every French head of state from 1824 to 1877—king, emperor, or president—was either overthrown by revolution or forced out of office. Was France trapped in a cycle of monarchy, republic, and empire, or did it advance stumblingly towards stability, finally achieved by the Third Republic? Two sets of revolutionary tensions were in play: a political conflict between governments and parliamentary assemblies, and a social conflict between the haves and havenots. François Furet has called the Third Republic the ‘harbour ‘ reached by France after a century of revolutionary turmoil, establishing the victory of parliament and universal male suffrage. A course can be charted towards this port from 1830, when Charles X fell for refusing to accept the verdict of elections, through February 1848, when the July Monarchy of Louis-Philippe fell for refusing to extend the franchise, to 1877, when President MacMahon repeated Charles ‘s action by calling elections to dispose of a chamber he did not like. However, Louis-Napoleon Bonaparte (Napoleon ‘s nephew) demonstrated that this parliamentary victory was not inevitable when he revived Bonapartism as both a political and a dynastic formula. His coup d ‘état of December 1851 finished the Second Republic and replaced it with an empire underpinned by elections; though he tacked back towards parliamentarianism in the 1860s, defeat in the Franco-Prussian war finished his experiment before it had been tested. Throughout the century, there were also eruptions of social revolution, which made the political revolutions of 1830 and 1848 possible, and which turned into civil war in June 1848 and in the Paris Commune of 1871.

Abstract On the morning of August 17, 1812, Napoleon’s Grande Armée paused on its long march towards Moscow, and began a terrifying barrage o artillery against the Russians defending the old city of Smolensk. The battle continued all day, and part of the next, and involved more than 110,000 soldiers. By nightfall the ‘holy city’, with its historic spires and golden domes, was on fire. Napoleon roused his exhausted equerry General Caulaincourt from his slumbers in order to admire the spectacle through his spy-glass. ‘It’s an eruption of Vesuvius!’, exclaimed Napoleon. ‘Is it not a fine sight?’ ‘It is horrible, sire’, replied the general.

Abstract Since the previous edition of this book went to press in 1999, the world has seen momentous eruptions in the relations between the Islamic and western worlds, as well as within the Islamic world. On Septem ber 11, 2.001 a group of Arab terrorists hijacked three airliners on do mestic flights in the United States and crashed them into the World Trade Center in New York and the Pentagon building near Washing ton, D.C., killing just under three thousand people. A fourth plane thought to have been intended for the White House or Capitol crashed on empty ground in Pennsylvania after a group of passengers, alerted by cell-phones, overcame the hijackers and forced the plane down, killing everyone on board. Spurred into action by the first external attack on the US mainland since the British burned the White House in the war of 1812., the US government, with widespread international support, declared war on the Taliban regime in Afghanistan. The Taliban were the known protectors of al-Qaeda, the ‘Foundation’ or ‘Base’ - an international terrorist network overseen and funded by Osama bin Laden, a member of a wealthy and influential Saudi Yemeni family. Prior to 9/11, al-Qaeda had mounted several attacks on US targets in Arabia and East Africa, including the suicide bombing of the USS Cole in Aden harbour in October 2.000, and the devas tating attacks on the US Embassies in Nairobi and Dar es Salaam, causing hundreds of deaths, most of them Kenyans and Tanzanians. Although bin Laden avoided claiming responsibility for these attacks, he praised the hijackers in interviews in the Muslim press and on videos delivered to the independent al-Jazeera channel in Qatar, seeing 9/11 as divine retribution for American atrocities against Muslims.’

Negative pressure is one of the metastable states of liquids at which it can be extended up to a certain limit without a gap of continuity. There are numerous experimental studies where a negative pressure up to 40 MPa has been obtained at laboratory conditions. However, these results of the experimental works were not practically implemented, as real liquids both in the nature and the technological processes contain impurities. Under certain kinetic and hydrodynamic conditions the waves of negative pressure in real liquids (crude oil, water, and water-based solutions) were observed. The wave of negative pressure is a turned soliton wave with one negative hump. It is a conservative wave, which maintains its shape and dimensions, and travels long distances with the speed of sound. An advanced technology of generation of the negative pressure wave in real systems allowed creating completely new energy saving technology. This technology based on negative pressure phenomenon has been already used for increasing oil production efficiency during various oil well operations, cleaning of oil well bore, and pipelines from various accumulations. It is shown that a new technology has a lot of potentials for bottom-hole cleaning operations, oil recovery enhancement, pipeline transportation, gas-lift operation etc. Negative pressure is known to be one of the metastable states at which liquids can be extended up to a certain limit. Theoretic evaluations show that in pure liquids negative pressure may reach large values while the liquid may stand significant extending efforts. For instance, the maximum negative pressure that may be sustained by ideally pure water is estimated as −109N/m2. It means that an imaginable rope of completely pure water with the diameter of 0.01m can sustain a huge extending effort more than 105 N. It is evident that the real experimental values of negative pressure are much less than the corresponding theoretic estimations. It is connected with the impossibility of obtaining ideally pure liquids without any “weak places” (gas bubbles, admixture, etc) and with the circumstance that in experience, the rupture often happens not in the liquid volume but on the surface touching the walls of the vessels weakened by the existence of thin films, embryos, etc. There are numerous results of the experimental work of static and dynamic character, where negative pressure has appeared in one or another degree [1]. In laboratory conditions, negative pressure apparently was first revealed in the experiences made by F. M. Donny (1843), who used degassed sulfuric acid and obtained negative pressure only −0.012 MPa. Among the further attempts of receiving bigger negative pressure, it is worth mentioning the experiences made by O.Reynolds, M.Bertelot and J.Meyer. Basing upon a centrifugal method and using mercury, L.J.Briggs obtained the record value of negative pressure (−42.5 MPa). But as a matter of fact, beginning from the first experiences by F. M. Donny, the main condition in the investigations for the appearance of negative pressure has been the homogeneous character of the liquid and high degree of the purity the liquid-vessel system. Significant values of negative pressure has been obtained under those conditions, however these results of a great scientific importance have no effective applications in practice as real liquids in Nature and technological processes are heterogeneous multicomponent systems. A long-term experimental work has been done to generate negative negative pressure in real liquid systems and investigate influence of this state on thermohydrodynamical characteristics of natural and technological processes [2,3]. Basing on the idea that negative pressure can be created due to the sudden character of extending efforts a direct wave of the negative pressure in real liquids (water, oil, solutions etc.) have been obtained experimentally. For impulsive entering into metastable (overheated) zone in a phase diagram “liquid-vapor” the pressure should drop so fast that the existing centers of evaporation (bubbles, embryos, admixtures etc.) would not be able to manifest themselves for this period. In these terms purity of the liquid is not decisive, and herewith there might exist states of an overheated liquid with the manifestation of negative pressure. It was determined that wave of the negative pressure resembling overturned soliton wave with one but negative peak propagates with speed of sound. The typical variation of the pressure in the petroleum stream in pipe is given in Figure 1. Reversed wave of the negative pressure was not recorded during the experiments. Evidently this is associated with considerable structural changes in the liquid after the passing of the direct wave. The arising negative pressure though being a short-term, results in a considerable overheating of the fluid system and leads to spontaneous evaporation and gas-emanation with the further cavitation regime. It was determined that after passing of the negative pressure wave hydraulic resistance in the system becomes much less, and significant increase of permeability of the porous medium and intensification of the filtration process take place. On the base of the investigations it was made a conclusion that any discharge in the hydraulic systems when the drop of the pressure requires much less time that relaxation of the pressure in the system inevitably results in the arising of rarefaction wave, in particular, the negative pressure wave [4]. The larger is the hydraulic system and the higher is the depression of the pressure, the more intensively the negative pressure wave may manifest itself. In certain terms waves of the positive pressure may be reflected from free surfaces, different obstacles, from contact surfaces between phases in the form of the reverse wave of the negative pressure. On this base there were presented numerous theoretical and experimental works on the simulation of the process, investigation of impact of the negative pressure on certain physical features of real systems [5]. The negative pressure wave may lead to very hard complications: showings of oil and gas leading sometimes to dreadful open fountains, borehole wall collapse, column crushing, gryphon appearance [6]. Analysis of numerous facts of complications, troubles in wells as water-oil-gas showings, crushing of columns, collapses, gryphon formation demonstrates that they arise usually as a result of round-trip operations in drilling of wells and their capital repairs. The negative pressure wave may be initiated by a sudden pulling of pipes or drilling equipment, as well as their sudden braking, quick opening of a valve at the well exit, etc, resulting in metastable extension of the working fluid agent. Though impulse negative pressure manifests itself as a significant dynamic factor, its structural consequences are more dangerous for an oil well. Moving along a well the negative pressure wave results in the spontaneous boiling of the water in the drilling fluid, and as a result of considerable reduction of its specific weight the hydrostatic column is “switched-off’ for some seconds and this may be sufficient for oil and gas showings of the well to be appeared accompanied often by crushing of columns and collapsing of wells due to great destroying energy manifestation. Negative pressure waves may be considered also as one of the dominant factors in geophysical processes, especially, in evolution and appearance of volcanic eruptions and earthquakes [7,8]. Extreme dynamic processes in the underground medium as a matter of fact can be considered as a synergetic manifestation of the negative pressure together with other thermohydrodynamical factors. The waves of negative pressure in the underground environment may be initiated by tectonic dislocations and faults as a result of different dynamic processes, dramatic decrease of pressure during the displacement of fluids and rocks. They may arise also in the form of a reverse waves as a result of reflection of ordinary seismic waves from different underground surfaces. On the basis of received results the method of artificial creation of negative pressure waves has been created [4]. The essence of the method is that negative pressure waves can be generated by means of discharge in hydraulic systems (pipes, wells, etc) when the drop of the pressure takes place during the characteristic time much less than that of pressure relaxation in the system. The greater is the volume of hydraulic system and the higher is the depression of the pressure, the more intensively the negative pressure wave may manifest itself. This method was taken as a basis of elaboration of principally new technologies and installations to increase effectiveness and efficiency of some oil recovery processes. It has been worked out and widely tested in field conditions new technologies on using of the negative pressure phenomenon for cleaning of oil producing hydraulic systems/well bore, pipeline/from various accumulations and increasing of effectiveness of oil producing at different well operation methods. The technology provides generation negative pressure waves in the well using the special mechanisms that leads to the shock depression impact upon the oil stratum, and as a result, to considerable growth in the oil influx, bottom-hole cleaning, accompanied by essential saving both reservoir and lifting energies, elimination and prevention of sandy bridging, paraffin, silt, water, etc. accumulations. For implementations of these technologies corresponding installations have been elaborated, in part, equipments for cleaning out of oil holes from sand plugs, increasing of efficiency and effectiveness of gas-lift well operations and bottom-hole pumping. In cleaning out of oil-holes from sand plugs the most operative and effective liquidation of different sand plugs irrespective of their rheological character is provided, associated with complete bottom-hole cleaning, essential increase of oil recovery and overhaul period. Elaborated equipment is simple and easy to use. Other comparatively advantageous application of the technology provides increase of efficiency of a gas-lift well operation, expressed in considerable reduction of a specific gas consumption associated with essential increase of oil recovery and overhaul period. The design of the equipment is reliable and simple to service. There are different modifications of the equipment for single-row, double-row lifts in packer and packerless designs. The introduced technologies have passed broad test in field conditions. The operative and complete cleaning of numerous oil wells was carried out, where the altitude of sand plugs varied from 20m to 180m; oil output of wells and their overhaul period have been increased and specific gas discharge reduced significantly.