ABSTRACT Many unusual phenomena in nature were recorded from the regions bordering the Mediterranean Sea from the second millennium BC up to AD 600. The ancient sources interpreted these as prodigies, messages from the gods, but rarely discussed their causes. Numerous reports of these portents were viewed as the illusions of eyewitnesses or the fabrications of ancient literary sources. Many modern authors have interpreted these portents as fabulous, or as astronomical or meteorological events. This thesis examines the portents that occur in the atmosphere, biosphere, lithosphere and hydrosphere and proposes that many are geophysical phenomena caused by tectonic activity, in particular earthquakes and volcanoes. Modern research on these incidents is examined to identify characteristics and causes, and texts from ancient philosophers and natural historians are investigated to see whether they were aware of these natural occurrences and if so, how they were produced. Portents that possess the characteristics of seismically-induced lights, cloud, fog, storms, anomalous animal behaviour, noises, and hydrological changes are collated in order to discuss individual events. Where possible, ancient examples are compared with modern well-documented episodes with the same features. In a majority of cases, these events have recurred in the same locations at later times. The proposal that many of these phenomena are caused by seismic activity offers an alternative to the suggestions of many modern scholars, who ascribe many of the luminous events to lightning, meteors or comets and some sonics to exploding meteors or thunderstorms. This reappraisal of the ancient portents vindicates the seemingly fantastic reports that occur in the ancient texts, especially some of the poetic or religious sources, and rehabilitates the reputation of the authors who have documented these events. In the process it also adds to the catalogue of geophysical phenomena caused by earthquakes in the classical world.

Thesis (M.F.A.)--Rochester Institute of Technology, 2008. / Typescript.

Inaug.-diss.--Munich. / Lebenslauf. "Literatur": p. 79.

xvii, 171 p. : ill. (some col.) / Crystals influence the migration of gas through magma. At low concentrations, they increase the bulk fluid properties, especially viscosity. At concentrations close to maximum packing, crystals form a rigid framework and magma cannot erupt. However, erupted pyroclasts with crystal contents close to the packing concentration are common at mafic volcanoes that exhibit Strombolian behavior. In this dissertation, I study the influence of solid particles on gas migration. I apply my results to Stromboli volcano, Italy, type locality of the normal Strombolian eruptive style, where gas moves through an essentially stagnant magma with crystallinity ∼50%. Specifically, I investigate the effect of crystals on flow regime, gas content (Chapter II), bubble concentration (number densities), bubble shapes, bubble sizes (Chapter III), and bubble rise velocities (gas flux) (Chapter IV). I find that gas-liquid flow regimes are not applicable at high particle concentrations and should be replaced by new, three-phase (gas-liquid-solid) regimes and that degassing efficiency increases with particle concentration (Chapter II). In Chapter III, I show that crystals modify bubble populations by trapping small bubbles and causing large bubbles to split into smaller ones and by modifying bubble shapes. In Chapter IV, I model Stromboli's crystal-rich magma as a network of capillary tubes and show that bubble rise velocities are significantly slower than free rise velocities in the absence of particles. In each chapter, I use analogue experiments to study the effect of different liquid and solid properties on gas migration in viscous liquids. I then apply my analogue results to magmatic conditions using simple parameterizations and/or numerical modeling or by comparing the results directly to observations made on crystal-rich volcanic rocks. Chapter V proposes a mechanism for Strombolian eruptions and gas migration through the crystalrich magma in which the effect of crystals is included. This model replaces the current twophase "slug" model, which cannot account for the high crystallinity observed at Stromboli. There are three appendices in this dissertation: a preliminary study of the influence of particles on gas expansion, image analysis methods, and the numerical code developed in Chapter IV. This dissertation includes previously published and unpublished co-authored material. / Committee in charge: Katharine Cashman, Chairperson; Alan Rempel, Member; Mark Reed, Member; Raghuveer Parthasarathy, Outside Member

This thesis investigates three problems in the general area of environmental fluid mechanics. The first two problems are related to liquid or gas flow through clay-water suspensions, with relevance for the underground storage of radioactive waste and also for understanding the mechanism of eruption in mud volcanoes. The third problem centres on the different problem of mixing in a turbulent buoyant plume. First, the injection of gas and water from a central source into a two-dimensional layer of clay confined between two circular horizontal plates is investigated. This provides a model of the potential pressurisation and failure of the seal rock around a radioactive waste repository as may arise if gas is continuously generated in the repository. As the gas injection pressure is gradually increased the cell walls deform and the clay moves radially outwards. However, at a critical radius, the liquid-clay interface becomes unstable and a series of channels propagate through the clay. When one of the channels reaches the edge of the domain the gas escapes and the pressure is released. As a result, the domain relaxes by elastic deformation and the clay seals the channel. In this way, continuous fluid injection leads to episodic release of gas from the cell. The second problem concerns the flow of mud along a vertical conduit driven by the combined effect of reservoir pressure and buoyancy associated with the gas injected at the base of the conduit. This represents an analogue model of the eruption of a mud volcano, in which mud rises from a deep reservoir to the surface. I find that the pressure associated with the reservoir and any buoyancy force produced by the migration of gas from deep in the reservoir to the surface leads to a continuous eruption if the net pressure is greater than the yield stress of the clay. If the reservoir pressure falls during such an event, the eruption will eventually stop, once the pressure reaches a dynamic yield stress condition. Only later, if the reservoir pressure increases to the static yield stress of the clay will the eruption start again, and this can lead to a series of eruption cycles which depend on the non-Newtonian rheology of the clay. In contrast, if this pressure is smaller than the yield stress of the clay, a series of episodic gas burst events can occur until the conduit is cleared of mud. The third problem relates to the mixing in a turbulent buoyant plume. Through a series of new experiments and some complementary theoretical modelling I show that the mixing in a turbulent plume is strongly affected by the eddies and leads to significant longitudinal dispersion in the flow. The implications of the modelling for determining the residence time distribution of the fluid in the plume is discussed.

abstract: Scientific and Cultural Interpretations of Volcanoes, 1766-1901 analyzes nineteenth-century conceptions of volcanoes through interdisciplinary literature and science studies. The project considers how people in the nineteenth century used science, aesthetics, and other ways of knowing to understand volcanoes and their operations. In the mid-eighteenth century, volcanoes were seen as singular, unique features of the planet that lacked temporal and terrestrial reach. By the end of the nineteenth century, volcanoes were seen as networked, environmental phenomena that stretched through geological time and geographic space. Scientific and Cultural Interpretations of Volcanoes, 1766-1901 offers a new historical understanding of volcanoes and their environmental connections, using literature and science to show how perceptions of volcanic time and space changed over 135 years. The first chapter, using texts by Sir William Hamilton, Hester Piozzi, and Priscilla Wakefield, argues that in the late eighteenth century important aspects of volcanoes, like their impact upon human life and their existence through time, were beginning to be defined in texts ranging from the scientific to the educational. The second chapter focuses on works by Sir Edward Bulwer-Lytton and Charles Lyell to demonstrate the ways that volcanoes were stripped of metaphysical or symbolic meaning as the nineteenth century progressed. The third chapter contrasts the 1883 eruption of Krakatoa with Constance Gordon-Cumming’s travels to Kīlauea. The chapter shows how even towards the end of the century, trying to connect human minds with the process of volcanic phenomenon was a substantial challenge, but that volcanoes like Kīlauea allowed for new conceptions of volcanic action. The last chapter, through a post-apocalyptic novel by M. P. Shiel, shows how volcanoes were finally beginning to be categorized as a primary agent within the environment, shaping all life including humanity. Ultimately, I argue that the change in thinking about volcanoes parallels today’s shift in thinking about global climate change. My work provides insight into how we imagine ecological catastrophes like volcanic eruptions or climate change in the past and present and what that means for their impact on people. / Dissertation/Thesis / Doctoral Dissertation English 2016

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The earth has always had a shifting climate with some periods having a colder climate then what is considered normal. This essay aims to investigate how the research of cold periods have changed. The purpose with this study is to investigate the most common beliefs researches has for the events of the climate catastrophe 536 and what factors lead to a possible population reduction. I will investigate three different reasons for this: Volcanic eruptions, plague, and climate. Another cold period the “little ice age”, 1300-1850, is used as an example and a theoretic comparison to the catastrophe of year 536 because the “little ice age” is a well-documented cold period of the later historical era. These two periods are interesting because they are booth cold periods. The first cold period lasted for a couple decades while the second cold period lasted for five hundred years. The bad climate situation depends of several different factors especially the fall in summer temperatures because the sun was hidden in a dust veil. The dust veil had been created after the big eruptions. The result of this study is that in general, the research has gone from more simple research to a more complex when knowledge of the complexity of the situation has evolved. The newer research has better access to natural science sources. The most common believes is that the volcanic eruptions or the Justinian plague were the biggest reason for a possible population reduction.

京都大学 / 新制・課程博士 / 博士(人間・環境学) / 甲第25389号 / 人博第1131号 / 京都大学大学院人間・環境学研究科相関環境学専攻 / (主査)教授 瀬戸口 浩彰, 教授 市岡 孝朗, 教授 西川 完途, 教授 井鷺 裕司 / 学位規則第4条第1項該当 / Doctor of Human and Environmental Studies / Kyoto University / DGAM

Depuis le début des années 80, les progrès technologiques de l'imagerie des fonds marins et l'exploration des marges continentales ont permis de découvrir et d'étudier de nombreuses morphologies du fond marin témoignant de la circulation des fluides dans la colonne sédimentaire et de leur expulsion. Dans cette étude des volcans de boue, nous proposons une méthode d'analyse innovante combinant une approche statistique automatisée incluant la détection et l'analyse de paramètres morphométriques avec une étude géologique classique. Nous avons utilisé un vaste jeu de données de géophysiques marines et géologiques, d’origines académiques et industrielles, à l’échelle du bassin oriental de la mer Méditerranée.Il ressort de cette analyse que le mécanisme de formation des volcans de boue est directement lié à une contrainte locale ou régionale pouvant avoir une origine tectonique ou gravitaire.Différents paramètres géologiques conditionnant les dimensions et formes des volcans de boue ont été étudiés permettant de proposer un modèle original de leur formation. La conception de ce modèle, qui se veut générique, permet de regrouper les paramètres constitutifs d’un système de volcan de boue en trois étapes spatiales, depuis la couche source jusqu’à l’expression superficielle. / Since the early 80s, technological advances of seabed imagery and exploration of continental margins allowed to discover and study numerous seabed features recording fluid circulation within the sediment column.In this study of mud volcanoes, we propose an innovative method of analysis combining an automated statistical approach including detection and analysis of morphometric parameters together with a classical geological study. We used broad homogenous academic and industrial marine geophysical and geological dataset, at the scale of Eastern Mediterranean sea.The analysis of these parameters shows that the mechanism of formation of the mud volcanoes is directly related to a local or regional constrain that may have a tectonic or gravitational origin.Various geological parameters conditioning the size and shape of mud volcanoes have been studied and lead to propose an original model for the formation of mud volcanoes. The design of this model, which is intended to be generic, makes it possible to group the constituent parameters of a mud volcano system in three spatial stages, from the source layer to the superficial expression.