Trondhjemitic and granitic melts formed by fractional crystallization of an olivine tholeiite from Reykjanes Peninsula, Iceland

2005 ◽  
Vol 142 (6) ◽  
pp. 651-658 ◽  
Author(s):  
E. MARTIN ◽  
O. SIGMARSSON
Keyword(s):  
Continental Crust ◽  
Fractional Crystallization ◽  
Significant Role ◽  
Major Element ◽  
Low Pressure ◽  
The Other ◽  
Olivine Tholeiite ◽  
Host Lava ◽  
Reykjanes Peninsula ◽  
Silicic Magmas

A pair of samples, from host lava and an included segregation vein from the Reykjanes Peninsula, Iceland, allows the assessment of a complete fractional crystallization of an olivine tholeiite at low pressure. The final product consists of silicic glasses with bimodal composition: trondhjemitic and more rarely granitic. Compilation of data on major element compositions of Icelandic silicic rocks reveals a clear difference from those of the segregation glasses. Fractional crystallization of basalts at low pressure is therefore not the most likely mechanism for the origin of silicic magmas in Iceland. Similar conclusions have been reached in studies on O- and Th-isotope compositions. On the other hand, the trondhjemitic compositions of the glasses in the segregation vein from Reykjanes Peninsula suggest that fractional crystallization of olivine tholeiites could have played a significant role during the formation of the very early continental crust.

The 1875 eruption of Askja volcano, Iceland: combined fractional crystallization and selective contamination in the generation of rhyolitic magma

1987 ◽  
Vol 51 (360) ◽  
pp. 183-202 ◽  
Author(s):  
R. Macdonald ◽  
R. S. J. Sparks ◽  
H. Sigurdsson ◽  
D. P. Mattey ◽  
D. W. McGarvie ◽  
...  
Keyword(s):  
Trace Element ◽  
Fractional Crystallization ◽  
Major Element ◽  
First Record ◽  
Isotopic Data ◽  
Rhyolitic Magma ◽  
Element Modelling ◽  
Relative Enrichment ◽  
Askja Volcano ◽  
Silicic Magmas

AbstractMajor and trace element and Sr, Nd and O isotopic data are presented for ferrobasalts, icelandites, rhyolites, mixed pumices and silicic xenoliths of the 1875 eruption of Askja. Trace element modelling and Sr and Nd data largely confirm previous major element calculations that fractional crystallization was dominant in the generation of the basalt-ferrobasalt-icelandite-rhyolite suite. Relative enrichment in Rb (and Th and U?), depletion in Cs, and low values of δ18O/16O, in the rhyolites are not explained by this mechanism alone. The silicic magmas were selectively contaminated by diffusion from partially molten granitic wall rocks, now found as xenoliths in the eruptive products, the process being particularly marked by lower δ18O and Cs/Rb ratios in the rhyolites than in the associated basalts. This is the first record of a combined fractional crystallization-selective contamination process in an Icelandic silicic complex.

The SADC Tribunal

2018 ◽  
Author(s):  
E. Tendayi Achiume
Keyword(s):  
Human Rights ◽  
Significant Role ◽  
Economic History ◽  
Southern African Development Community ◽  
The Other ◽  
Legal Decision ◽  
African Development ◽  
Sociopolitical Context ◽  
Judicial Lawmaking

This chapter uses the trajectory of the Southern African Development Community (“SADC”) Tribunal to chart sociopolitical constraints on international judicial lawmaking. It studies the SADC Tribunal backlash case, which paved the way for a curtailment of the Tribunal’s authority, stripping the Tribunal of both private access and its jurisdiction over human rights. Showing how jurisprudential engagement with sociopolitical context plays a significant role in explaining the Tribunal's loss of authority, the chapter introduces the concept of sociopolitical dissonance. Sociopolitical dissonance is a state that results when a legal decision contradicts or undermines deeply held norms that a given society or community forms on the basis of its social, political, and economic history. Sociopolitical resonance, on the other hand, describes the quality of affirming or according with a given society's norms as informed by its sociopolitical history.

scholarly journals Sustainable Consumer Behavior in Purchasing, Using and Disposing of Clothes

2021 ◽  
Vol 13 (15) ◽  
pp. 8333
Author(s):  
Mirella Soyer ◽  
Koen Dittrich
Keyword(s):  
Consumer Behavior ◽  
The Netherlands ◽  
Multiple Regression ◽  
Significant Role ◽  
Social Motivation ◽  
The Other ◽  
Social Evaluation ◽  
Sustainable Practices ◽  
Usage Phase ◽  
The Core

In this study we investigate how consumers in The Netherlands can be persuaded to adopt sustainable practices when purchasing, using and disposing of clothes. This study investigates the attitude-behavior gap for the sustainable choices for purchase, use and disposing of clothes. For each consumption phase we ran a two-step multiple regression. The findings showed that the importance of the factors vary in the three consumption phases. For purchasing and disposal decisions, the core motivator social motivation predicts sustainable practices best, while it has no role in the usage phase. The factor ability appeared to have a significant role in the disposal phase, but not in the other phases. Finally, the trigger appears to lower the consumers’ ability in the purchasing phase, while it enhances the core motivator social evaluation in the disposal phase.

Traditional Polity and the Dynamics of Change in India

1963 ◽  
Vol 22 (1) ◽  
pp. 5-10 ◽  
Author(s):  
Joan Bondurant
Keyword(s):  
Intellectual History ◽  
Significant Role ◽  
The Other ◽  
The One

The title of this essay begins with the word traditional and it moves towards the idea of change. As is well known, these terms—tradition and change—are not opposites, nor are they to be understood in contradistinction to one another. It is important in this context to avoid the temptation to treat them as contradictory or to draw contrasts between what one considers on the one hand traditional, and on the other, changing. One cannot accurately speak of what was as over against what will be, or what is becoming. Nor can one view the ancient as opposed to that which is modern. Clearly, the opposite of change is permanence and persistence, and is not—at least not necessarily—to be couched in terms of the traditional. One need only to remind oneself that among the most compelling elements in the West's intellectual history is the idea of progress, to understand that there are indeed traditions in which the notion of change itself has played a significant role. And so it does not follow that "traditional Indian polity" is a set of concepts to be placed over against the "dynamics of change"—quite the contrary, as I shall try to show in what follows.

Significance of analysis of the mechanism of fingermarks formation, sizes and location – casework examples

2018 ◽  
Vol 301 ◽  
pp. 44-52
Author(s):  
Tomasz Kowalski ◽  
Keyword(s):  
Significant Role ◽  
Special Interest ◽  
The Other ◽  
Fatal Accident ◽  
Preliminary Stage ◽  
Additional Information ◽  
Expert Opinions ◽  
First Case ◽  
Initial Stage

The aim of the article to present the role of analysing the manner of generating fingermarks in the investigative proceedings. These examinations are based on the analysis of the location of the marks on a given background and aim at providing the requesting party additional information about the circumstances of the investigated incident. The Author refers to two unusual cases, in which Voivodeship Police Command Forensic Laboratory issued expert opinions in the area of fingerprint identification. In the first case, at the initial stage of the proceedings the circumstances and recovered evidential fingermarks indicated a fatal accident or manslaughter by means of a firearm. In the other case at the preliminary stage recovered evidence did not allow identification of the perpetrator due to incorrectly selected exhibits. These cases would not be off special interest to us without the significant role of proper recovering of fingermarks and their analysis in a broader context than just identification.

Major element chemistry of the geothermal sea-water at Reykjanes and Svartsengi, Iceland

1978 ◽  
Vol 42 (322) ◽  
pp. 209-220 ◽  
Author(s):  
Stefán Arnórsson
Keyword(s):  
Ground Water ◽  
Major Element ◽  
Sea Water ◽  
Geothermal Water ◽  
Ionic Exchange ◽  
Geothermal Waters ◽  
Major Element Chemistry ◽  
Element Chemistry ◽  
Geothermal Fields ◽  
Reykjanes Peninsula

SummaryHigh-temperature geothermal fields in Iceland represent localized anomalies of hot, altered rock in the uppermost part of the crust, which coincide with points of maximum tectonic/magmatic activity. These points correspond to the intersection of oblique fault swarms to the plate boundaries. Geothermal activity under mid-ocean ridges follows probably similar tectonic/magmatic anomalies.Due to high permeability sea-water invades the bed-rock of the Reykjanes Peninsula, Iceland, and is overlain by a variably thick lens of dilute ground water of meteoric origin. The variable degree of salinity of geothermal waters in the Reykjanes Peninsula has resulted from different degree of mixing of fresh ground water with the underlying sea-water-ground-water in the downflow zones around the geothermal fields. At Reykjanes the geothermal water represents heated sea-water without any freshwater mixing. The difference in the composition of sea-water or sea-water/fresh water mixtures and the geothermal waters is due to basalt/water interaction at elevated temperatures. The major-element chemistry of the geothermal water represents an equilibrium composition at the relevant aquifer temperatures. The activities of silica, calcium, sulphate, and carbonate are thus limited by the solubilities of quartz, anhydrite, and calcite. Fluoride activity is thought to be controlled by an ionic exchange reaction where it substitutes for hydroxyl groups in phyllosilicates. The ratios of individual cations and hydrogen ion are governed by ionic exchange equilibria with hydrothermal minerals, probably smectite and chlorite. The equilibrium pH for the Reykjanes and Svartsengi geothermal waters is 5·5 and 5·1 respectively. Sea-water will become somewhat acid upon heating to more than about 300 °C and equilibration with basalt, the acidity increasing with temperature.

Relative roles of source composition, fractional crystallization and crustal contamination in the petrogenesis of Andean volcanic rocks

1984 ◽  
Vol 310 (1514) ◽  
pp. 675-692 ◽  
Keyword(s):  
Subduction Zone ◽  
Continental Crust ◽  
Fractional Crystallization ◽  
Magma Mixing ◽  
Volcanic Rocks ◽  
Crustal Contamination ◽  
Oceanic Lithosphere ◽  
Alkaline Basalt ◽  
Complex Process ◽  
Heterogeneous Mantle

There are well established differences in the chemical and isotopic characteristics of the calc-alkaline basalt—andesite-dacite-rhyolite association of the northern (n.v.z.), central (c.v.z.) and southern volcanic zones (s.v.z.) of the South American Andes. Volcanic rocks of the alkaline basalt-trachyte association occur within and to the east of these active volcanic zones. The chemical and isotopic characteristics of the n.v.z. basaltic andesites and andesites and the s.v.z. basalts, basaltic andesites and andesites are consistent with derivation by fractional crystallization of basaltic parent magmas formed by partial melting of the asthenospheric mantle wedge containing components from subducted oceanic lithosphere. Conversely, the alkaline lavas are derived from basaltic parent magmas formed from mantle of ‘within-plate’ character. Recent basaltic andesites from the Cerro Galan volcanic centre to the SE of the c.v.z. are derived from mantle containing both subduction zone and within-plate components, and have experienced assimilation and fractional crystallization (a.f.c.) during uprise through the continental crust. The c.v.z. basaltic andesites are derived from mantle containing subduction-zone components, probably accompanied by a.f.c. within the continental crust. Some c.v.z. lavas and pyroclastic rocks show petrological and geochemical evidence for magma mixing. The petrogenesis of the c.v.z. lavas is therefore a complex process in which magmas derived from heterogeneous mantle experience assimilation, fractional crystallization, and magma mixing during uprise through the continental crust.

scholarly journals The psychology behind Sialkot tragedy

2018 ◽  
Vol 8 (4) ◽  
pp. 139-145
Author(s):  
Farheen Nasir ◽  
Khadeeja Naim
Keyword(s):  
Significant Role ◽  
The Other ◽  
Archival Research ◽  
Malignant Behavior ◽  
Obedience To Authority ◽  
Role Conceptualization

Objective: This paper analyzes the Sialkot tragedy which had happened in Sialkot, Pakistan in 2010 in which two innocent brothers were lynched in broad daylight and in front of hundreds of people including policemen, thus committing sin of violence, and cruelty. Method: Archival research was done to explore two important questions; what had led to the killing of those innocent boys and why didn’t anyone do anything to stop it? Result: Detailed analyses of the case revealed the following causal elements with significant role; conceptualization of self and that of the other, semantic framing and stereotypic labeling, psychological distancing, rationalization, obedience to authority, deindividuation, and evil as inaction. Conclusion: It is important to note that these factors need not be antecedently conditional or necessary for the prevalence of malignant behaviors but helps to understand their impact under negative circumstances.Keywords: violence; cruelty; malignant behavior

scholarly journals Managing relationships through repetition

Pragmatics ◽  
2019 ◽  
Vol 29 (1) ◽  
pp. 57-82
Author(s):  
Saeko Machi
Keyword(s):  
Significant Role ◽  
The Other ◽  
Japanese Language ◽  
Talk Show ◽  
The Third ◽  
Short Period ◽  
Points Of View ◽  
Tv Talk Show ◽  
Dynamic Relationships

Abstract This study examines cross-speaker repetition in triadic conversations in the Japanese language. For the analysis, three sets of triadic conversations between close friends taken from a TV talk show are used. The results reveal that repetition in triadic conversations performs distinctive functions that are not observed in dyadic conversations: repetition often takes place between only two participants of the triad and allows the two to team up and strengthen their bond exclusively (teaming repetition), or even playfully tease the third participant (teasing repetition). Repetition is also shared between the three participants. In such cases, it allows the participants to create an instant bond by joking or referring to shared circumstances (immediate threefold repetition), or to gradually establish rapport by connecting their utterances and co-constructing a story (repetition relay). All these types of repetition express the participants’ points of view and contribute efficiently to their relationships that shift from moment to moment. The study further demonstrates cases in which one participant makes good use of various repetition types in a short period of time and efficiently allocates thoughts and feelings to the other two participants. The study concludes that repetition plays a significant role in Japanese conversation, helping speakers to converse smoothly and manage the dynamic relationships efficiently.

scholarly journals Cinema and Cyberphobia: Internet Tropes in Film and Television

2016 ◽  
Vol 4 (1) ◽  
pp. 36-53
Author(s):  
Lauren Rosewarne
Keyword(s):  
Social Media ◽  
Risk Factor ◽  
Significant Role ◽  
Online Gaming ◽  
The Other ◽  
The Internet ◽  
Second Nature ◽  
Film And Television ◽  
Socially Excluded ◽  
The Web

Despite the widespread embrace of the Internet and the second nature way we each turn to Google for information, to social media to see our friends, to netporn and Netflix for recreation, film and television tells a very different story. On screen, a character dating online, gaming online or shopping online, invariably serves as a clue that they’re somewhat troubled: they may be a socially excluded nerd at one end of the spectrum, through to being a paedophile or homicidal maniac seeking prey at the other. On screen, the Internet is frequently presented as a clue, a risk factor and a rationale for a character’s deviance or danger. While the Internet has come to play a significant role in screen narratives, an undercurrent of many depictions – in varying degrees of fervour – is that the Web is complicated, elusive and potentially even hazardous. This paper draws from research conducted for my book Cyberbullies, Cyberactivists, Cyberpredators: Film, TV, and Internet Stereotypes (Rosewarne, 2016). While that volume provided an analysis of the denizens of the Internet through the examination of over 500 film and television examples – profiling screen stereotypes such as netgeeks, neckbeards, and netaddicts – this paper focuses on some of the recurring themes in portrayals of the Internet, shedding light on the how, and perhaps most importantly why, the fear of the technology is so common. This paper presents a series of themes used to frame the Internet as negative on screen including dehumanisation, the Internet as a badlands, the Web as possessing inherent vulnerabilities and the cyberbogeyman.

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