Information about open-system magma chambers derived from textures in magmatic enclaves: the Kameni Islands, Santorini, Greece

2005 ◽  
Vol 142 (6) ◽  
pp. 637-649 ◽  
Author(s):  
M. B. HOLNESS ◽  
V. M. MARTIN ◽  
D. M. PYLE
Keyword(s):  
Major Element ◽  
Detailed Examination ◽  
Lava Flows ◽  
Dihedral Angles ◽  
Distinct Population ◽  
Magma Chambers ◽  
Original Population ◽  
Mafic Enclaves ◽  
The Past ◽  
Dacitic Lava

Post-caldera eruptions of Santorini, Greece, over the past 3000 years resulted in the formation of the Kameni Islands, which comprise a series of compositionally similar dacitic lava flows. Each lava flow has a distinct population of partially-crystalline mafic enclaves, which we propose were derived from the break-up of a layer of replenishing magma responsible for triggering the eruption. Five of the recent flows (erupted in 1570, 1939, 1940, 1941 and 1950) include enclaves of essentially identical andesitic bulk compositions, which formed by crystallization of originally aphyric melts prior to eruption. Detailed examination of angles subtended at the junctions between pairs of plagioclase grains demonstrates that enclaves from each flow have a characteristic textural signature, with distinct differences in the extent of quench-related modification of the original population of dihedral angles formed by impingement of growing grains. These variations suggest that the temperature difference between the host dacite and the replenishing andesite at the time of layer overturn and eruption differed between flows. The uniformity of major element compositions of both the replenishing magma and the host dacitic lava flows demonstrates that the critical parameter in determining the timing of layer-overturn is the pre-eruptive H2O content of both host dacite and replenishing magma. We suggest that the replenishing magma responsible for two of the three eruptions in the period 1939–1941 was significantly wetter than that responsible for the later 1950 eruption. The enclaves with the least amount of quench-related modification occur in the 1570 flow. We suggest that in this case the intruding magma was relatively dry.

scholarly journals Montenegrin-Albanian Linguistic Border: In Search of “Balanced Language Contact”

Slovene ◽  
2018 ◽  
Vol 7 (2) ◽  
pp. 258-302 ◽  
Author(s):  
Maria S. Morozova ◽  
Alexander Yu. Rusakov
Keyword(s):  
Language Contact ◽  
Detailed Examination ◽  
Speech Community ◽  
Community Members ◽  
The Past ◽  
External Relations ◽  
History Of ◽  
Contact Situation ◽  
Linguistic Behavior ◽  
The Village

The article aims to clarify the notion of “balanced language contact” and to model the situation of a language contact (in the present and the past) in one of the ethnically and linguistically mixed regions of the Montenegrin-Albanian linguistic border. The study focuses on the situation in the bilingual community of thevillageofVelja Gorana, located in the area of Mrkovići inSouthern Montenegro. The community of the village, as it seems at a first glance, provides a good example of a “balanced contact” situation. The language situation in Velja Gorana is described in the article as a set of micro-situations, or scenarios, developing on family and individual levels. Attention is paid not only to the communication in the family domain, but also to the external relations of the community members. Following on from this material, the authors attempt to develop a methodology for assessing the role of both languages in such communities in general, showing which factors influence individual linguistic behavior; how this behavior may change during an individual lifetime; how the different speakers’ strategies amalgamate in what can be considered as behavior of a multilingual speech community. Analyzing the information on the history of Velia Gorana, in particular, conducting a detailed examination of the origins, genealogies and marriage strategies of its families, allows the authors to reconstruct the mechanisms for the development of “linguistic exogamy” in the community of Velja Gorana and to make assumptions about the nature of the contact situation in this region in the past.

Rhetorical Economy in Augustine's Theology

2021 ◽  
Author(s):  
Brian Gronewoller
Keyword(s):  
Detailed Examination ◽  
Augustine Of Hippo ◽  
Scriptural Interpretation ◽  
The Past ◽  
Divine Activity ◽  
Clean Break ◽  
Previous Scholarship ◽  
Divine Order

Augustine of Hippo (AD 354–430) studied and taught rhetoric for nearly two decades until, at the age of thirty-one, he left his position as professor of rhetoric in Milan to embark upon his new life as a Christian. But this was not a clean break. Previous scholarship has done much to show us that Augustine integrated rhetorical ideas about texts and speeches into his thought on homiletics, the formation of arguments, and scriptural interpretation. Over the past few decades a new movement among scholars has begun to show that Augustine also carried rhetorical concepts into areas of his thought that were beyond the typical purview of the rhetorical handbooks. This study contributes to this new movement by providing a detailed examination of Augustine’s use of the rhetorical concept of economy in his theologies of creation, history, and evil, in order to gain insights into these fundamental aspects of his thought. Ultimately, this book finds that Augustine used rhetorical economy as the logic by which he explained a multitude of tensions within, and answered various challenges to, these three areas of his thought as well as others with which they intersect—including his understandings of providence, divine activity, and divine order.

A quantitative study of five thousand years of volcanism on Sao Miguel, Azores

1978 ◽  
Vol 288 (1352) ◽  
pp. 271-319 ◽  
Keyword(s):  
Quantitative Study ◽  
Basaltic Magma ◽  
Volcanic Eruptions ◽  
Lava Flows ◽  
Explosive Eruptions ◽  
Lateral Movement ◽  
The Past ◽  
Pumice Fall ◽  
Eruptive Fissures ◽  
Fall Deposits

The activity of the three stratovolcanoes on the island of Sao Miguel is documented by tephrochronology, and during the past 5000 years a total of some 57 volcanic eruptions have taken place, mostly of magnitudes 4-6 on Tsuya’s scale. Approximately half were trachytic, and half basaltic. Each stratovolcano has a caldera within which each has had one historic eruption. The trachytic eruptions were predominantly explosive, and most took place from vents situated within the calderas. Isopach and isograde maps of most of the resulting pumice fall deposits are given. The basaltic eruptions produced both lava flows and pyroclastics, and isopach and isograde maps are given for some of the main fall deposits. The Agua de Pau volcano has had particularly large explosive eruptions, several of them (including Fogo A, the largest in the past 5000 years) being of plinian type. The output of the three volcanoes over the 5000 years is equivalent to 4.6 km 3 of dense rock, at which rate the exposed parts of the volcanoes could have accumulated in 150000 years. At least half of the erupted material is trachytic, a proportion typical of the entire accessible parts of the volcanoes. The 50 known eruptive vents of the past 5000 years are distributed in a zone 55 km long by 8 km wide which may lie above a major fracture zone. Some eruptive fissures trend obliquely across this zone, suggesting right-lateral movement along the fracture. Basaltic eruptions were confined to a much smaller area than in the preceding millennia perhaps due to the formation, at the time of the great Fogo A eruption 5000 years ago, of a broad trachytic magma chamber underlying the Agua de Pau and Furnas volcanoes which basaltic magma has since been unable to penetrate.

scholarly journals Sine-skewed toroidal distributions and their application in protein bioinformatics

Biostatistics ◽  
2020 ◽  
Author(s):  
Ameijeiras-Alonso Jose ◽  
Christophe Ley
Keyword(s):  
Simple Algorithm ◽  
Maximum Likelihood Estimators ◽  
Dihedral Angles ◽  
Random Numbers ◽  
Symmetric Model ◽  
Asymptotic Results ◽  
The Past ◽  
Normalizing Constant ◽  
New Models ◽  
Dependence Measures

Summary In the bioinformatics field, there has been a growing interest in modeling dihedral angles of amino acids by viewing them as data on the torus. This has motivated, over the past years, new proposals of distributions on the torus. The main drawback of most of these models is that the related densities are (pointwise) symmetric, despite the fact that the data usually present asymmetric patterns. This motivates the need to find a new way of constructing asymmetric toroidal distributions starting from a symmetric distribution. We tackle this problem in this article by introducing the sine-skewed toroidal distributions. The general properties of the new models are derived. Based on the initial symmetric model, explicit expressions for the shape and dependence measures are obtained, a simple algorithm for generating random numbers is provided, and asymptotic results for the maximum likelihood estimators are established. An important feature of our construction is that no extra normalizing constant needs to be calculated, leading to more flexible distributions without increasing the complexity of the models. The benefit of employing these new sine-skewed toroidal distributions is shown on the basis of protein data, where, in general, the new models outperform their symmetric antecedents.

The Amisk Group: An Aphebian(?) Island Arc Deposit

1975 ◽  
Vol 12 (12) ◽  
pp. 2021-2035 ◽  
Author(s):  
Mel R. Stauffer ◽  
A. C. Mukherjee ◽  
J. Koo
Keyword(s):  
Major Element ◽  
Regional Metamorphism ◽  
Island Arc ◽  
Lava Flows ◽  
Chemical Analyses ◽  
Pyroclastic Rocks ◽  
Andesitic Lava ◽  
Ore Bodies ◽  
Flin Flon ◽  
Garnet Zone

The Amisk Group (Aphebian?) near Flin Flon, Manitoba, consists dominantly of andesitic lava flows and pyroclastic rocks, with minor basalt, dacite, rhyolite, and epiclastic rocks. These have undergone regional metamorphism ranging from chlorite to garnet zone, and locally have been sheared intensely.Major element chemical analyses indicate that intensely sheared Amisk rocks near the Flin Flon and Schist Lake Cu–Zn ore bodies have undergone considerable metasomatism. The unsheared, regionally metamorphosed rocks have undergone significantly less metasomatism, and the compositions of the least-altered of these suggest an island arc tholeiite chemical affinity.The lithology, primary structures, and major-element compositions of lavas within the Amisk Group suggest deposition may have been in an island arc environment.

Observations on ergot in cereal crops

1942 ◽  
Vol 32 (4) ◽  
pp. 457-464 ◽  
Author(s):  
W. A. R. Dillon Weston ◽  
R. Eric Taylor
Keyword(s):  
Detailed Examination ◽  
Cereal Crops ◽  
Triticum Vulgare ◽  
Relative Susceptibility ◽  
The Past ◽  
The One

Several cases of ergot in barley encountered in 1941 have been investigated, and records have been examined of the occurrence of ergot in cereal crops in this country during the past 24 years. These indicate that ergot is found more frequently on rye than on wheat, barley or oat, this, in descending order, being their relative susceptibility. A more detailed examination of records of the occurrence on rye in the seasons 1939–42 indicates that the disease is more prevalent in northern districts than elsewhere; of 500 acres of rye surveyed in Suffolk and Norfolk in 1942 only three crops comprising 80 acres showed a trace of ergot. It is rare on both wheat and barley and little is known as to the susceptibility of their varieties, although on several occasions it has been noted on Rivet wheat, and has been recorded on Rivet and Triticum vulgare crosses. In this country there is no record of it having been found on oat, apart from the one specimen found in a field of mixed corn in Cambridgeshire.

scholarly journals Deciphering ocean carbon in a changing world

2016 ◽  
Vol 113 (12) ◽  
pp. 3143-3151 ◽  
Author(s):  
Mary Ann Moran ◽  
Elizabeth B. Kujawinski ◽  
Aron Stubbins ◽  
Rob Fatland ◽  
Lihini I. Aluwihare ◽  
...  
Keyword(s):  
Analytical Chemistry ◽  
Major Element ◽  
Molecular Level ◽  
Clear Definition ◽  
Vast Number ◽  
The Past ◽  
Technological Developments ◽  
Ocean Carbon ◽  
The Individual ◽  
Numerical Complexity

Dissolved organic matter (DOM) in the oceans is one of the largest pools of reduced carbon on Earth, comparable in size to the atmospheric CO2reservoir. A vast number of compounds are present in DOM, and they play important roles in all major element cycles, contribute to the storage of atmospheric CO2in the ocean, support marine ecosystems, and facilitate interactions between organisms. At the heart of the DOM cycle lie molecular-level relationships between the individual compounds in DOM and the members of the ocean microbiome that produce and consume them. In the past, these connections have eluded clear definition because of the sheer numerical complexity of both DOM molecules and microorganisms. Emerging tools in analytical chemistry, microbiology, and informatics are breaking down the barriers to a fuller appreciation of these connections. Here we highlight questions being addressed using recent methodological and technological developments in those fields and consider how these advances are transforming our understanding of some of the most important reactions of the marine carbon cycle.

Tying the Knot

2021 ◽  
Author(s):  
Rebecca Probert
Keyword(s):  
Social Practice ◽  
Detailed Examination ◽  
Primary Sources ◽  
Individual Choice ◽  
Marriage Law ◽  
The Past ◽  
Wide Range ◽  
The Law ◽  
First Time

The Marriage Act 1836 established the foundations of modern marriage law, allowing couples to marry in register offices and non-Anglican places of worship for the first time. Rebecca Probert draws on an exceptionally wide range of primary sources to provide the first detailed examination of marriage legislation, social practice, and their mutual interplay, from 1836 through to the unanticipated demands of the 2020 coronavirus pandemic. She analyses how and why the law has evolved, closely interrogating the parliamentary and societal debates behind legislation. She demonstrates how people have chosen to marry and how those choices have changed, and evaluates how far the law has been help or hindrance in enabling couples to marry in ways that reflect their beliefs, be they religious or secular. In an era of individual choice and multiculturalism, Tying the Knot sign posts possible ways in which future legislators might avoid the pitfalls of the past.

Skull metastasis of thyroid carcinoma

1985 ◽  
Vol 63 (4) ◽  
pp. 526-531 ◽  
Author(s):  
Yoshihide Nagamine ◽  
Jiro Suzuki ◽  
Ryuich Katakura ◽  
Takashi Yoshimoto ◽  
Naoya Matoba ◽  
...  
Keyword(s):  
Thyroid Cancer ◽  
Thyroid Carcinoma ◽  
Clinical Course ◽  
Detailed Examination ◽  
Thyroid Tumor ◽  
Content Type ◽  
Skull Metastasis ◽  
The Past ◽  
The Mean ◽  
Well Differentiated

✓ Over the past 33 years the authors have treated 12 cases of skull metastasis from thyroid carcinoma, accounting for 2.5% of a total of 473 cases of thyroid cancer. A study of these 12 cases revealed the following characteristics. 1) The mean age of the patients was 60.4 years and the predominant incidence was in the seventh decade of life. 2) The incidence of skull metastasis from thyroid cancer was higher among women than among men. 3) The primary sign was a soft hemispheric tumor resting on the skull. 4) The tumors were rich in vascularity with osteolytic changes in the skull. 5) The average period from diagnosis of the thyroid tumor until thyroidectomy was 14.3 years, and until discovery of the skull metastasis was 23.3 years. The clinical course was thus very long. 6) The most frequent histopathological presentation was follicular adenocarcinoma. Such lesions were morphologically well differentiated, with little pleomorphism and atypism, but detailed examination showed infiltration into the vascular lumen or capsule. 7) The mean survival time in these patients was 4.5 years from the time of diagnosis. The prognosis in this lesion was relatively poor, considering its long clinical course.

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