Cause Of Eruption Research Articles

Dynamic processes in an active region in the initial and impulsive phases of the eruptive flare event on June 7, 2011

We present the results of an analysis of Hα monochromatic and spectral observations obtained at the Crimean Astrophysical Observatory for an impressive filament eruption during a flare occurred on June 7, 2011. Our ground-based observations are combined with data acquired by multiple instruments onboard the Solar Dynamics Observatory (SDO/AIA, SDO/HMI). The evolution and dynamics of the eruptive process, the cause of eruption, the structure of the line-of-sight velocity field and fine internal structure of the eruptive filament are studied and a number of physical parameters of the eruptive filament are determined.
 The results of the analysis have shown that: 1) The evolution of the filament eruption consists of two phases: the slow-rise phase, which began about two hours before the flare onset, and the fast-rise phase, which began almost simultaneously with the flare onset. 2) The eruptive filament had a very complex internal structure and complicated line-of-sight velocity field. The filament does not erupt as a single structure. Several discrete massive absorption fragments are seen with a large number of fine-structure elements inside fragments with different velocities, as well as many plasma blobs that detach from the fragments. 3) The motion of the filament fragments is a combination of rotational motion around the axis of the fragment and a movement as a whole towards the observer. The velocities of such plasma motions are determined. 4) Hα line profiles show a large variety of contrast values, Doppler half-widths and Doppler shifts in eruptive filament elements.

Динамические процессы в активной области в начальный и импульсный периоды эруптивного вспышечного события 7 июня 2011 года

Представлены результаты анализа Hα монохроматических и спектральных наблюдений впечатляющей эрупции волокна во время эруптивной вспышки 7 июня 2011 г., полученных в Крымской астрофизической обсерватории. Наземные наблюдения рассматривались совместно с наблюдательными данными, полученными на инструментах на борту Solar Dynamics Observatory (SDO/AIA, SDO/HMI). Изучена эволюция и динамика эруптивного процесса, причина эрупции, структура поля лучевых скоростей и тонкая внутренняя структура эруптивного волокна и определен ряд физических параметров в эруптивном волокне. Результаты анализа показали следующее: 1. Эволюция эрупции волокна состояла из двух фаз: фазы медленного подъема, начавшейся примерно за два часа до начала вспышки, и фазы быстрого подъема, которая началась практически одновременно с началом вспышки. 2. Эруптивное волокно имело очень сложную внутреннюю структуру и сложное поле лучевых скоростей. Оно не выбрасывалось как единая структура. Эрупция состояла из нескольких крупных поглощающих фрагментов с большим количеством тонкоструктурных элементов внутри фрагмента с разными лучевыми скоростями, а также многих сгустков плазмы, оторванных от фрагмента. 3. Движение фрагментов представляло собой комбинацию вращательного движения вокруг оси фрагмента и движения в целом по направлению к наблюдателю. Определены скорости этих движений. 4. Профили линии Hα показывают большое разнообразие значений контраста, доплеровских полуширин и доплеровских смещений в элементах эруптивного волокна.

EVALUATION OF DRUG ERUPTION RELATED HELICOBACTER PYLORI ERADICATION THERAPY

The number of patients who undergo Helicobacter pylori (HP) eradication therapy has been increasing since it became covered by insurance in Japan. As such, an increasing number of patients develop drug eruption as a result of HP eradication therapy. In the present study, we describe the clinical course of 28 patients who were treated at our hospital for drug eruption following HP eradication therapy between April 2008 and March 2016. The majority of the patients were women (21 women, 7 men). The average length of time from the start of treatment to the onset of eruption was 7.6 days. A drug-induced lymphocyte stimulation test (DLST) was performed in 10 patients. Amoxicillin was the most common cause of eruption, with 6 patients testing positive. Patients who were considered likely to have developed sensitivity prior to the treatment required the systemic administration of steroids. On the other hand, symptoms were relieved with topical steroids in some of the patients who were considered likely to have developed sensitivity during the course of treatment. Since penicillin antibiotics have long been used, some patients may have become sensitized without being aware of this. Our findings highlight the need for the careful management of patients developing sensitivity prior to treatment as they require the systemic administration of steroids.

Down the Crater: Where Magmas are Stored and Why They Erupt

Magmas are erupted from a wide range of depths. Olivine compositions, for example, indicate magma storage in the lower crust and upper mantle, while clinopyroxene and amphibole record middle to upper crust storage. Pre-eruptive magmas also often cool by 100–300 °C, frequently at middle–upper crust depths, indicating clogged, ephemeral volcanic pathways. These coolings imply that mafic recharge is not a sufficient cause for eruption and that crystallization-induced vapor saturation is a more proximal eruption trigger. But an improved understanding of eruption mechanisms require precise identifications of what are herein termed “ultimate”, “proximal,” and “immediate” causes of eruption.

Amphibole thermometers and barometers for igneous systems and some implications for eruption mechanisms of felsic magmas at arc volcanoes

Calcic, igneous amphiboles are of special interest as their compositional diversity and common occurrence provide ample potential to investigate magmatic processes. But not all amphibole-based barometers lead to geologically useful information: recent and new tests reaffirm prior studies (e.g., Erdman et al. 2014), indicating that amphibole barometers are generally unable to distinguish between experiments conducted at 1 atm and at higher pressures, except under highly restrictive conditions. And the fault might not lie with experimental failure. Instead, the problem may relate to an intrinsic sensitivity of amphiboles to temperature ( T ) and liquid composition, rather than pressure. The exceptional conditions are those identified by Anderson and Smith (1995): current amphibole barometers are more likely to be useful when T Amp = Fe Amp /(Fe Amp +Mg Amp ) Such analysis reveals that amphiboles are vastly less complex than may be inferred from published catalogs of end-member components. Most amphiboles, for example, consist largely of just three components: pargasite [NaCa 2 (Fm 4 Al)Si 6 Al 2 O 22 (OH) 2 ], kaersutite [NaCa 2 (Fm 4 Ti)Si 6 Al 2 O 23 (OH)], and tremolite + ferro-actinolite [Ca 2 Fm 5 Si 8 O 22 (OH) 2 , where Fm = Fe+Mn+Mg]. And nearly all remaining compositional variation can be described with just four others: alumino-tschermakite [Ca 2 (Fm 3 Al 2 )Si 6 Al 2 O 22 (OH) 2 ], a Na-K-gedrite-like component [(Na,K)Fm 6 AlSi 6 Al 2 O 22 (OH) 2 ], a ferri-ferrotschermakite-like component [Ca 2 (Fm 3 Fe 2 3+ )Si 6 Al 2 O 22 (OH) 2 ], and an as yet unrecognized component with 3 to 4 Al atoms per formula unit (apfu), 1 apfu each of Na and Ca, and 4 Ti(Fe 3+ ,Al)Si 5 Al 3 O 23 (OH). None of these components, however, are significantly pressure ( P ) sensitive, leaving the Al-in-amphibole approach, with all its challenges, the best existing hope for an amphibole barometer. A new empirical barometer based on D Al successfully differentiates experimental amphiboles crystallized at 1 to 8 kbar, at least when multiple P estimates, from multiple amphibole compositions, are averaged. Without such averaging however, amphibole barometry is a less certain proposition, providing ±2 kbar precision on individual estimates for calibration data, and ±4 kbar at best for test data; independent checks on P are thus needed. Amphibole compositions, however, provide for very effective thermometers, here based on D Ti , D Na , and amphibole compositions alone, with precisions of ±30 oC. These new models, and tests for equilibrium, are collectively applied to Augustine volcano and the 2010 eruption at Merapi. Both localities reveal a significant cooling and crystallization interval (>190–270 oC) at pressures of 0.75 to 2.2 kbar at Augustine and Merapi, respectively, perhaps the likely depths from which pre-eruption magmas are stored. Such considerable intervals of cooling at shallow depths indicate that mafic magma recharge is not a proximal cause of eruption. Rather, eruption triggering is perhaps best explained by the classic “second boiling” concept, where post-recharge cooling and crystallization drive a magmatic system toward vapor saturation and positive buoyancy.

Diaper Dermatitis: Clinical Characteristics and Differential Diagnosis

A diverse group of diseases can cause skin conditions in the diaper area including those which are directly caused by diapers or the diaper environment, some which are not directly due to, but are worsened by, the wearing of diapers, and those which are independent of the presence of the diaper or its resulting environment. Many of these conditions are limited to this area of the skin, but others extend to skin outside this area, and some are signs of systemic disease. We review many of the important causes of eruptions in the diaper area and emphasize key points in the differential diagnosis.

A rare cause of eruption in infancy: Cutaneus mastocytosis

Skin eruptions and pruritis are one of the most common causes of emergency room admissions. Coexistence of these two symptoms are indicates a wide variety of diseases complicates planning the differential diagnosis. Certainly, a careful and thorough history and physical examination is helpful for the diagnosis. Mastocytosis is a rare condition in the group of disorders characterized by skin eruptions and pruritus. However persisting and exacerbations of eruptions in history and a positive Darier sign in physical examination calls remind this rarely seen diagnosis. In this article, approach to cases with mastocytosis will be evaluated by presenting a case with urticeria pigmentosa which was diagnosed sixteen months after patient’s complaints had started who received palliative treatments repeatedly during this period.

Melt inclusion evidence for magma evolution at Mutnovsky volcano, Kamchatka

AbstractMutnovsky Volcano, located in Kamchatka, Russia, is a young volcano that has formed a series of four overlapping stratocones over its approximately 80 ka history. Erupted products at Mutnovsky range in composition from basalts to dacites; basalts are the most common. In this study, melt inclusions from representative samples of all erupted compositions from all four eruptive centers were analyzed to investigate the causes of the compositional heterogeneity, melt evolution, and pre‐eruptive magma dynamics. Melt inclusions from Mutnovsky were sampled in olivine, plagioclase, orthopyroxene, and clinopyroxene. The melt inclusion data represent a wide range of melt compositions, from basalt through rhyolite. Geochemical modeling of melt inclusion data, combined with field evidence and chemical zoning of plagioclase phenocrysts, indicates that fractional crystallization and magma mixing produced the range of erupted bulk rock compositions. The measured variability of melt inclusion compositions in each host mineral phase indicates that different host minerals trapped unique melts that evolved separately from one another. The melt inclusion data suggest that individual melt portions evolved by fractional crystallization, perhaps in different magma chambers, within the Mutnovsky plumbing system, and were mixed prior to eruption. Our data do not indicate whether the mixing events were the cause of eruption or are simply the manifestation of the eruption process.

Fixed drug eruption in Bangladeshi population: confirmed by provocative test

Fixed drug eruption is designated as a typical allergic reaction occurring due to exposure to a medicine. This common dermatological condition is often being ignored for its causative agent as well as the patient's sufferings sometimes become unpredictable. The objective of this large population study is to identify the causative agents responsible for fixed drug eruption. The study is comprised of 120 suspected patients of fixed drug eruption. History, classic clinical features of well circumscribed erythema, edema, and violaceous pigmentation, and the recurrence of the eruptions on the same sites upon re-administering drug were used as diagnostic criteria. The drug(s) causing allergic reactions were confirmed by provocation tests. The incidence of drug eruption was found distributed in 0.62% amongst all dermatology outpatient attendees. The male to female ratio recorded was 7:2. The highest number of cases was observed within in the age group of 21-35 years. The provocation tests were positive in 92 among 120. The genitalia and lips/face were the most commonly affected site for fixed drug eruption. The drug sulphonamide (including co-trimoxazole) accounted for the highest number of cases of eruptions (28.33 %). The other drugs, in order of frequency, responsible for the cause of eruptions were identified as nonsteroidal anti-inflammatory drugs, tetracycline, metronidazole, herbal medicine, paracetamol, fluconazole, penicillin, Griseofulvin, and homeopathic medicine, etc. Drug reactions are very frequently experienced by dermatologists in their day-to-day practice. The patients are often ignorant of the drugs consumed and often do not accept them as an etiologic factor. A detailed drug history as well as the complaints will be helpful before undertaking the provocation test.

Endoscopic Removal of an Ectopic Tooth in Maxillary Sinus

Ectopic teeth erupted in the maxillary sinus are rarely reported. Although the causes of eruption of a tooth into the maxillary sinus are unclear, some clinical conditions are suspected to be responsible, such as developmental disturbances (cleft palate), displacement of teeth by trauma, interventions or cyst, infection, genetic factors, crowding, and dense bone. Most cases of ectopic teeth in the maxillary sinus are asymptomatic and are occasionally diagnosed thanks to routine radiographic investigations.The aim of this article is to present and discuss the surgical management of an ectopic third molar in the roof of the maxillary sinus.

Seed‐crop size and eruptions of North American boreal seed‐eating birds

Summary Eruptions occur when a species appears in unusually high densities within and often outside of its normal range. We used 30 years of Christmas Bird Counts combined with cone/seed‐crop data on boreal coniferous trees, breeding bird surveys, and weather records to test correlates of winter eruptions by 11 species of primarily boreal North American seed‐eating birds. Eruptions of six species in eastern (red‐breasted nuthatch Sitta canadensis L., black‐capped chickadee Parus atricapillus L., evening grosbeak Hesperiphona vespertina Cooper, pine grosbeak Pinicola enucleator L., red crossbill Loxia curvirostra L. and bohemian waxwing Bombycilla garrulus L.) and five species in western North America (pine grosbeak, pine siskin Carduelis pinus Wilson, evening grosbeak, bohemian waxwing and red‐breasted nuthatch) correlated with a combination of large coniferous seed crops in the previous year followed by a poor crop. Breeding population size in the year of the eruption was also correlated positively with the event in two of the species. Eruptions in these species apparently occur when large boreal seed crops resulting in high population densities (via high overwinter survivorship and/or high reproductive success) are confronted with a relatively poor seed crop the next autumn. Eruptions of common redpolls Carduelis flammea L. and black‐capped chickadees in the west followed only large seed crops the previous year, suggesting that high density is a more important factor leading to eruptions than seed crop failure. The opposite was true for white‐winged crossbills (Loxia leucoptera Gmelin) in the east, where eruptions correlated only with poor current year seed crops. This was the only species supporting the ‘seed‐crop failure’ hypothesis as the sole cause of eruptions. Purple finches Carpodacus purpureus Gmelin erupted following years when breeding population densities were high for reasons apparently unrelated to the seed crop. Eruptions of three species in both regions were uncorrelated with any of the variables tested. We conclude that seed crops of boreal trees play a pivotal role in causing eruptions for a majority of boreal species, usually through a combination of a large seed crop resulting in high population densities followed by a poor seed crop rather than seed‐crop failure alone. Weather conditions were not a significant factor correlating with eruptions in any of the species.

Observations at Costa Rican volcano offer clues to causes of eruptions

Recent measurements of ground deformation at an active volcano show great promise for elucidating the processes that lead to volcanic eruptions. A long‐term effort to continuously monitor ground deformation over a very wide bandwidth using state‐of‐the‐art geodetic, seismic, and acoustic instruments at Arenal Volcano in Costa Rica is producing high‐quality recordings of harmonic tremor and explosive events and offers an exciting opportunity to explore possible lunar periodicities in volcanic eruptivity.

Petrochemistry of quaternary pumiceous pyroclastic products in southern Guadeloupe (F.W.I.)

Pumiceous pyroclastic products are present as flows and falls at several stages of the evolution of the southern Guadeloupe volcanic island. An understanding of this volcanism had to rely on detailed petrochemical data of these products to complement similar data for effusive rocks so as to yield complete stratigraphical coverage. On the other hand most pumiceous rocks are more or less conspicuousily banded suggesting that mixing phenomena occurred to different degrees in their genesis. Three major classes of pumiceous products are found: (1) the Axial Chain deposits (2.0–0.5 My) are characterized by An90, 75-55 + En55 + Wo42En37 + Usp35-37 ± Fo68 ± Hble, SiO2 60%, SiO2/Th 35.6, and La/Th 3.9. Banded samples have components that differ in evolution indices by about 50%; (2) the Bouillante Chaine pyroclastics (0.3–0.1 My) consist of scattered deposits with variable mineralogical and geochemical compositions that seem to have erupted from a number of small eruptive centers. Qz-dacitic pumice is common with An90, 70-45 + En66-56 + Usp32-38 + Ilm94 + Hble ± Wo40-42En40-42, SiO2 62%, SiO2/Th 22.9, and La/Th >4. Mixed pumice samples have highly contrasted evolution indices differing by up to 120%; (3) the Pintade pumice flows and falls correspond to the major pyroclastic event (approx. 10 km3) in the southern Basse Terre area. They are characterized by An85-70 + En66-56 + Usp32-37 ± Wo42En42, SiO2/Th 18.7-22?6, and La/Th 3.0-4.0. Banded pumice lumps are scarce and show slight compositional contrasts; differences in evolution indices do not exceed 38%. Axial and Bouillante chain pyroclastics and Grande Decouverte volcano pumice respectively, form two different families in trace element plots. Minor elements in pyroxenes also are distinctive. These trends are similar to those obtained for effusive rocks and define comagmatic series. Major and trace element data for the separated components of inhomogeneous pumice in each formation always plot in the corresponding series. These chemical discriminants can be used to attribute samples of unknown provenance to a given volcanic ensemble. An inverse relationship between differences in evolution indices in inhomegeneous pumice and the volume of any single eruptive sequence is noted. This is an indication that pumiceous pyroclastic rocks were erupted from a zoned magma chamber. We favor an interpretation where zonation is produced by influx of less envolved magma in superficial differentiated chambers which is a direct cause for eruption.

Zoster-like Eruption due to Echovirus 6

A unilateral vesiculobullous eruption associated with fever was seen on the neck, shoulder, and upper part of the chest of a 7-year-old boy. Although three dermatomes in all were involved, the lesions resembled herpes zoster. The patient had had varicella in infancy. Culture of fluid from several bullae yielded echovirus 6; however, and serum neutralizing antibody to this virus rose in titer from 1:32 to 1:640. It is suggested that echovirus 6 and other enteroviruses may cause a number of vesicular eruptions that resemble herpes zoster and similar infections. Viral culture, while often difficult to obtain, is the only way to identify the cause of eruptions like this one.

Fluoride Toothpastes as a Cause of Acne-like Eruptions

To the Editor.— I read the letter from Dr Saunders on fluoride toothpastes as a cause of acne-like eruptions.1His observations are interesting and possibly important. However, I would like to offer the following comments: (1) The ingestion of fluorides neither precipitates nor aggravates acne.2(2) Fluorides are much more closely related chemically to chlorides than to iodides or bromides, although all are halogens. There is no evidence that chlorides per se cause or irritate acne. (3) Dr Saunders has not established that nonfluoride toothpastes do not cause acneiform eruptions. (4) A survey among dentists indicates that, due to the efforts of Madison Avenue, 60% to 80% of all people, and especially women, use fluoride toothpastes. Therefore, 46 out of 46 cases is less impressive. (5) It has not been established that the fluorides in the toothpaste are the actual cause of the eruption described by Dr Saunders;

Magma mixing: petrological process and volcanological tool

Magma mixing is a widespread, if not universal igneous phenomenon of variable importance. The evidence for magma mixing is found primarily in glassy tephra; the consolidation of lava obscures the evidence. Inclusions of glass in big crystals in tephra, because of their greater range in composition compared to the whole rock and the residual glass, indicate that the big crystals were derived from separate systems which mixed together prior to and during eruption. The observed or reconstructed concentration of K 2O in inclusions of glass in large crystals represent the composition of the contaminant and host systems. Selective enrichment in K 2O during entrapment of melt by growing crystals is shown to be negligible. The weight percents of K 2O in host, contaminant and residual glass and bulk rock determine the proportions of contaminant and host required to yield either the residual glass or bulk rock. In several cases the proportion of contaminant required is substantially larger than the proportion of crystals in the hybrid magma; therefore, by heat budget argument, the contaminant was partly liquid when contamination began. In some tephra individual phenocrysts contain glasses which are more silicic toward the center of the crystal indicating that the crystal grew from a melt whose composition changed in the opposite sense to that expected for progressive solidification of a closed system. Space time associations of compositionally distinct glassy tephra with contaminated magmas suggest coexistence of basaltic and silicic melts within magma systems. Evidence of contamination is present in most tephra studied so far. Magma mixing appears to be the prevalent process whereby contamination occurs. Magma mixing seems to be particularly evident in systems where there is independent evidence for a vapor-saturated magma reservoir. Probably vapor saturation promotes mixing in magma systems. Magma mixing probably is an important mechanism of compositional diversification (differentiation) of volcanic rocks from continental margin and possibly other environments. Textural evidence of the onset of magma mixing can be related to disturbance of a complex reservoir immediately before ascent and eruption. Thus, conditions before mixing can be ascribed to the reservoir. In this way it is possible to learn about the reservoir: its composition, its diversity, its depth, its walls. It is also possible to learn about the causes of eruption: whether by increase in gas pressure due to either progressive consolidation, or heating from below by an injection of hot magma, or by encounter with ground water; whether by buoyant rise. Evaluation of these problems requires also a thorough knowledge of the chronology of particular eruptions. Thus, magma mixing is a useful volcanological tool.

The Krakatoa Eruption 1

THE inquiry, instituted in consequence of a Government resolution of October 4, 1883, into tne nature, the extent, and the consequences of the volcanic eruptions of Krakatoa, has led to various remarkable results of which a short account is given here. A detailed report is in course of preparation, but will not appear for some months, as the making of numerous illustrative maps and plates will take much time. The inquiry did not extend solely to the islands of the Straits of Sunda, but also to the coast countries of the Lampong districts, Bantam and Batavia, which were partly or entirely destroyed. In the Straits of Sunda the islands of Merak, Toppershoedje, Dwars in den Weg (Thwart the Way), Seboekoe, Sebesi, Lagoendi, Krakatoa, Taboean, Prince's Island, the Monnikrotsen (the Monk's Rocks), and Meeuwen Island (Mew's Island), were visited; further, the coast-strip from Ketimbang to Kalianda, and inland as far as Kesoegihan, besides the foot of the Radja Bassa; the coast of Hoeroen to Telok Betong, and the environs of the capital; the southern part of Semangka Bay (the northern part was inaccessible through pumice-stone), the kampoengs Tampang and Blimbing, near the Vlakken Hoek, Java's First Point (Java Head), and the coasts of Tjiringin and Anjer to Merak. The voyage, which lasted seventeen days, was made by the hopperbarge (small steamer) Kediri, commander 't Hoen, given for the inquiry by the temporary chief of the Batayian Harbour Works. About the causes of eruptions there is usually not much to be said, yet in this case something has been ascertained. Krakatoa, namely, lies with a few other volcanoes on a rent or fissure in the crust of the earth which runs across the Straits of Sunda, and of which I indicated the probable existence for the first time three years ago. Along such a fissure little shiftings of the earth's crust are possible, by which a pressure is exercised upon the molten substances below the crust. It is also possible that along such a rent—however tightly closed by the neighbouring stone-layers—the water may more easily than elsewhere flow to the regions under the earth. If this water comes in contact with the molten substances, steam at high temperature and high pressure is formed, and this steam may be considered as the chief motor of most, if not all, volcanic eruptions.