scholarly journals Role of sediment in generating contemporaneous, diverse “type” granitoid magmas

Geology ◽  
2021 ◽  
Author(s):  
Shan Li ◽  
Calvin F. Miller ◽  
Wang Tao ◽  
Wenjiao Xiao ◽  
David Chew

Granite typology categorizes granitoid rocks based upon distinguishing characteristics that are interpreted to indicate sources, conditions of generation, and, by implication, tectonic setting. Complexities of elemental and isotopic geochemistry, however, commonly preclude simple typological interpretation and suggest more complex petrogenetic histories. Granitoids from the Songpan-Ganzi terrane in the eastern Tibetan Plateau were emplaced within a short interval (~15 m.y.). They display mineralogical and geochemical characteristics that are consistent with a wide range of proposed typologies (I-, S-, and A-type; high Ba-Sr and adakitic variants). Despite their close spatial and temporal association, these granitoids exhibit diversity in geochemical characteristics that indicates a broad spectrum of contributing sources. Radiogenic isotope data reveal a continuum from primitive to evolved crustal compositions; i.e., 87Sr/86Sr(t) = 0.704–0.715 and εNd(t) = +2 to –11. All granitoid “types” have variable but commonly high zircon δ18O (+4.1‰ to +11.6‰) and low whole-rock Li-B-Mg isotopic ratios compared to mantle and/or seawater (δ7Li = +5.1‰ to –3.2‰; δ11B = –10.7‰ to –16.5‰; δ26Mg = –0.23‰ to –0.59‰). These stable isotopic compositions suggest that the Songpan-Ganzi granitic magmas of all “types” had contributions from sediment, ranging from minor to dominant. The highly variable isotopic compositions of the granitoids rule out a single homogeneous source for these diverse yet contemporaneous granitoids. Their compositional variability may have been significantly influenced by sedimentary contributions, and these results demonstrate the difficulty of straightforward assignment and interpretation of granitoids using conventional typology.

2021 ◽  
Author(s):  
Banafsheh Vahdati ◽  
Seyed Ahmad Mazaheri

<p>Mashhad granitoid complex is part of the northern slope of the Binalood Structural Zone (BSZ), Northeast of Iran, which is composed of granitoids and metamorphic rocks. This research presents new petrological and geochemical whole-rock major and trace elements analyses in order to determine the origin of granitoid rocks from Mashhad area. Field and petrographic observations indicate that these granitoid rocks have a wide range of lithological compositions and they are categorized into intermediate to felsic intrusive rocks (SiO<sub>2</sub>: 57.62-74.39 Wt.%). Qartzdiorite, tonalite, granodiorite and monzogranite are common granitoids with intrusive pegmatite and aplitic dikes and veins intruding them. Based on geochemical analyses, the granitoid rocks are calc-alkaline in nature and they are mostly peraluminous. On geochemical variation diagrams (major and minor oxides versus silica) Na<sub>2</sub>O and K<sub>2</sub>O show a positive correlation with silica while Al<sub>2</sub>O<sub>3</sub>, TiO<sub>2</sub>, CaO, Fe<sub>2</sub>O<sub>3</sub>, and MgO show a negative trend. Therefore fractional crystallization played a considerable role in the evolution of Mashhad granitoids. Based on the spider diagrams, there are enrichments in LILE and depletion in HFSE. Low degrees of melting or crustal contamination may be responsible for LILE enrichment. Elements such as Pb, Sm, Dy and Rb are enriched, while Ba, Sr, Nd, Zr, P, Ti and Yb (in monzogranites) are all depleted. LREE enrichment and HREE depletion are observed in all samples on the Chondrite-normalized REE diagram. Similar trends may be evidence for the granitoids to have the same origin. Besides, LREE enrichment relative to HREE in some samples can indicate the presence of garnet in their source rock. Negative anomalies of Eu and Yb are observed in monzogranites. Our results show that Mashhad granitoid rocks are orogenic related and tectonic discrimination diagrams mostly indicate its syn-to-post collisional tectonic setting. No negative Nb anomaly compared with MORB seems to be an indication of non-subduction zone related magma formation. According to the theory of thrust tectonics of the Binalood region, the oceanic lithosphere of the Palo-Tethys has subducted under the Turan microplate. Since the Mashhad granitoid outcrops are settled on the Iranian plate, this is far from common belief that these granitoid rocks are related to the subduction zones and the continental arcs. The western Mashhad granitoids show more mafic characteristics and are possibly crystallized from a magma with sedimentary and igneous origin. Thus, Western granitoid outcrops in Mashhad are probably hybrid type and other granitoid rocks, S and SE Mashhad are S-type. Evidences suggest that these continental collision granitoid rocks are associated with the late stages of the collision between the Iranian and the Turan microplates during the Paleo-Tethys Ocean closure which occurred in the Late Triassic.</p>


Author(s):  
Peter Elias ◽  
D. F. Strong

ABSTRACTFourteen granitoid plutons studied in the Baie d'Espoir area of southern Newfoundland are divisible into a northern group of eight and a southern group of six. The former tend to be undeformed, have thermal aureoles, and intrude greenschist facies Ordovician and Silurian rocks of the Dunnage zone following a period of folding and thrusting towards the SE. Four Rb-Sr whole-rock isochrons yield similar ages around 430 Ma for these plutons, fixing the deformation within early Silurian times. The latter plutons syntectonically intruded without aureole effects, and are all foliated and elongate parallel to the regional fabric of amphibolite facies gneisses and migmatites of the Gander zone. Whole-rock Rb-Sr isochrons around 350 Ma for both syntectonic and post-tectonic plutons indicate a rapid metamorphism, deformation, intrusion and uplift of the Gander zone in this area. There appear to be no systematic relationships between petrological and geochemical characteristics of the plutons and their tectono-stratigraphic setting. This study conclusively invalidates earlier hypotheses that deformed granitoid rocks of the Gander zone are older than the undeformed granitoids of the Dunnage zone; indeed, just the reverse is true.


2008 ◽  
pp. 61-76
Author(s):  
A. Porshakov ◽  
A. Ponomarenko

The role of monetary factor in generating inflationary processes in Russia has stimulated various debates in social and scientific circles for a relatively long time. The authors show that identification of the specificity of relationship between money and inflation requires a complex approach based on statistical modeling and involving a wide range of indicators relevant for the price changes in the economy. As a result a model of inflation for Russia implying the decomposition of inflation dynamics into demand-side and supply-side factors is suggested. The main conclusion drawn is that during the recent years the volume of inflationary pressures in the Russian economy has been determined by the deviation of money supply from money demand, rather than by money supply alone. At the same time, monetary factor has a long-run spread over time impact on inflation.


2018 ◽  
Vol 7 (2) ◽  
pp. 117-128 ◽  
Author(s):  
Erin Sullivan ◽  
Marie Louise Herzfeld-Schild

This introduction surveys the rise of the history of emotions as a field and the role of the arts in such developments. Reflecting on the foundational role of the arts in the early emotion-oriented histories of Johan Huizinga and Jacob Burkhardt, as well as the concerns about methodological impressionism that have sometimes arisen in response to such studies, the introduction considers how intensive engagements with the arts can open up new insights into past emotions while still being historically and theoretically rigorous. Drawing on a wide range of emotionally charged art works from different times and places—including the novels of Carson McCullers and Harriet Beecher-Stowe, the private poetry of neo-Confucian Chinese civil servants, the photojournalism of twentieth-century war correspondents, and music from Igor Stravinsky to the Beatles—the introduction proposes five ways in which art in all its forms contributes to emotional life and consequently to emotional histories: first, by incubating deep emotional experiences that contribute to formations of identity; second, by acting as a place for the expression of private or deviant emotions; third, by functioning as a barometer of wider cultural and attitudinal change; fourth, by serving as an engine of momentous historical change; and fifth, by working as a tool for emotional connection across communities, both within specific time periods but also across them. The introduction finishes by outlining how the special issue's five articles and review section address each of these categories, while also illustrating new methodological possibilities for the field.


Author(s):  
C. Claire Thomson

The first book-length study in English of a national corpus of state-sponsored informational film, this book traces how Danish shorts on topics including social welfare, industry, art and architecture were commissioned, funded, produced and reviewed from the inter-war period to the 1960s. For three decades, state-sponsored short filmmaking educated Danish citizens, promoted Denmark to the world, and shaped the careers of renowned directors like Carl Th. Dreyer. Examining the life cycle of a representative selection of films, and discussing their preservation and mediation in the digital age, this book presents a detailed case study of how informational cinema is shaped by, and indeed shapes, its cultural, political and technological contexts.The book combines close textual analysis of a broad range of films with detailed accounts of their commissioning, production, distribution and reception in Denmark and abroad, drawing on Actor-Network Theory to emphasise the role of a wide range of entities in these processes. It considers a broad range of genres and sub-genres, including industrial process films, public information films, art films, the city symphony, the essay film, and many more. It also maps international networks of informational and documentary films in the post-war period, and explores the role of informational film in Danish cultural and political history.


2020 ◽  
pp. 102-109
Author(s):  
Svetlana Alekseevna Raschetina ◽  

Relevance and problem statement. Modern unstable society is characterized by narrowing the boundaries of controlled socialization and expanding the boundaries of spontaneous socialization of a teenager based on his immersion in the question arises about the importance of the family in the process of socialization of a teenager in the conditions of expanding the space of socialization. There is a need to study the role of the family in this process, to search, develop and test research methods that allow us to reveal the phenomenon of socialization from the side of its value characteristics. The purpose and methodology of the study: to identify the possibilities of a systematic and anthropological methodology for studying the role of the family in the process of socialization of adolescents in modern conditions, testing research methods: photo research on the topic “Ego – I” (author of the German sociologist H. Abels), profile update reflexive processes (by S. A. Raschetina). Materials and results of the study. The study showed that for all the problems that exist in the family of the perestroika era and in the modern family, it acts for a teenager as a value and the first (main) support in the processes of socialization. The positions well known in psychology about the importance of interpersonal relations in adolescence for the formation of attitudes towards oneself as the basis of socialization are confirmed. Today, the frontiers of making friends have expanded enormously on the basis of Internet communication. The types of activities of interest to a teenager (traditional and new ones related to digitalization) are the third pillar of socialization. Conclusion. The “Ego – I” method of photo research has a wide range of possibilities for quantitative and qualitative analysis of the socialization process to identify the value Pillars of this process.


Author(s):  
Simon Goldhill

How did the Victorians engage with the ancient world? This book is an exploration of how ancient Greece and Rome influenced Victorian culture. Through Victorian art, opera, and novels, the book examines how sexuality and desire, the politics of culture, and the role of religion in society were considered and debated through the Victorian obsession with antiquity. Looking at Victorian art, it demonstrates how desire and sexuality, particularly anxieties about male desire, were represented and communicated through classical imagery. Probing into operas of the period, the book addresses ideas of citizenship, nationalism, and cultural politics. And through fiction—specifically nineteenth-century novels about the Roman Empire—it discusses religion and the fierce battles over the church as Christianity began to lose dominance over the progressive stance of Victorian science and investigation. Rediscovering some great forgotten works and reframing some more familiar ones, the book offers extraordinary insights into how the Victorian sense of antiquity and our sense of the Victorians came into being. With a wide range of examples and stories, it demonstrates how interest in the classical past shaped nineteenth-century self-expression, giving antiquity a unique place in Victorian culture.


2016 ◽  
Vol 1 (1) ◽  
pp. 4
Author(s):  
Marymol Koshy ◽  
Bushra Johari ◽  
Mohd Farhan Hamdan ◽  
Mohammad Hanafiah

Hypertrophic cardiomyopathy (HCM) is a global disease affecting people of various ethnic origins and both genders. HCM is a genetic disorder with a wide range of symptoms, including the catastrophic presentation of sudden cardiac death. Proper diagnosis and treatment of this disorder can relieve symptoms and prolong life. Non-invasive imaging is essential in diagnosing HCM. We present a review to deliberate the potential use of cardiac magnetic resonance (CMR) imaging in HCM assessment and also identify the risk factors entailed with risk stratification of HCM based on Magnetic Resonance Imaging (MRI).


2019 ◽  
Author(s):  
Andrew Romine ◽  
Kin Yang ◽  
Malkanthi Karunananda ◽  
Jason Chen ◽  
Keary Engle

A weakly coordinating monodentate heteroaryl thioether directing group has been developed for use in Pd(II) catalysis to orchestrate key elementary steps in the catalytic cycle that require conformational flexibility in a manner that is difficult to accomplish with traditional strongly coordinating directing groups. This benzothiazole thioether, (BT)S, directing group can be used to promote oxidative Heck reactivity of internal alkenes providing a wide range of products in moderate to high yields. To demonstrate the broad applicability of this directing group, arene C–H olefination was also successfully developed. Reaction progress kinetic analysis provides insights into the role of the directing group in each reaction, which is supplemented with computational data for the oxidative Heck reaction. Furthermore, this (BT)S directing group can be transformed into a number of synthetically useful functional groups, including a sulfone for Julia olefination, allowing it to serve as a “masked olefin” directing group in synthetic planning. In order to demonstrate this synthetic utility, natural products (+)-salvianolic acid A and salvianolic acid F are formally synthesized using the (BT)S directed C–H olefination as the key step.


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