A granophyre from Coire Uaigneich, Isle of Skye, containing quartz paramorphs after tridymite (Plate XIII)

1953 ◽  
Vol 30 (223) ◽  
pp. 263-276 ◽  
Author(s):  
L. R. Wager ◽  
D. S. Weedon ◽  
E. A. Vincent
Keyword(s):  
Final Stage ◽  
Second Generation ◽  
Textural Features ◽  
The West ◽  
Plate Xiii ◽  
Igneous Intrusions ◽  
Igneous Province ◽  
Narrow Belt ◽  
Isle Of Skye

The narrow belt of granophyre lying to the west of Blaven in the Isle of Skye showed so admirably the effects of chilling that a series of specimens was collected by one of us (L.R.W.) and found to contain, in the chilled marginal rock, phenoerysts of tridymite, now inverted to quartz. In the Thulean Tertiary igneous province former tridymite is known from certain acid lavas, for example, the Tardree rhyolite (von Lasaulx, 1877) and certain Icelandic liparites (Hawkes, 1916), and from metamorphosed arkoses adjacent to basic igneous intrusions (Harker, 1908, 1932), but it has not previously been noted in the intrusive acid rocks. In addition to phenocrysts of tridymite inverted to quartz, there is present in the groundmass of the unchilled granophyre a second generation of inverted tridymite crystals, surrounded by a final stage of quartz and felspar which has crystallized with normal microgranitic textures. Some of the textural features resemble those of the normal Skye granophyres, while others resemble certain metamorphosed arkoses.

Lithostratigraphy of the Palaeoproterozoic Hekpoort Formation (Pretoria Group, Transvaal Supergroup), South Africa

2020 ◽  
Vol 123 (4) ◽  
pp. 655-668
Author(s):  
N. Lenhardt ◽  
W. Altermann ◽  
F. Humbert ◽  
M. de Kock
Keyword(s):  
South Africa ◽  
Bushveld Complex ◽  
Sedimentary Rocks ◽  
Type Locality ◽  
Large Igneous Province ◽  
Braided River ◽  
River Systems ◽  
The West ◽  
Igneous Province ◽  
Transvaal Supergroup

Abstract The Palaeoproterozoic Hekpoort Formation of the Pretoria Group is a lava-dominated unit that has a basin-wide extent throughout the Transvaal sub-basin of South Africa. Additional correlative units may be present in the Kanye sub-basin of Botswana. The key characteristic of the formation is its general geochemical uniformity. Volcaniclastic and other sedimentary rocks are relatively rare throughout the succession but may be dominant in some locations. Hekpoort Formation outcrops are sporadic throughout the basin and mostly occur in the form of gentle hills and valleys, mainly encircling Archaean domes and the Palaeoproterozoic Bushveld Complex (BC). The unit is exposed in the western Pretoria Group basin, sitting unconformably either on the Timeball Hill Formation or Boshoek Formation, which is lenticular there, and on top of the Boshoek Formation in the east of the basin. The unit is unconformably overlain by the Dwaalheuwel Formation. The type-locality for the Hekpoort Formation is the Hekpoort farm (504 IQ Hekpoort), ca. 60 km to the west-southwest of Pretoria. However, no stratotype has ever been proposed. A lectostratotype, i.e., the Mooikloof area in Pretoria East, that can be enhanced by two reference stratotypes are proposed herein. The Hekpoort Formation was deposited in a cratonic subaerial setting, forming a large igneous province (LIP) in which short-termed localised ponds and small braided river systems existed. It therefore forms one of the major Palaeoproterozoic magmatic events on the Kaapvaal Craton.

Annual Meeting of the (American) African Studies Association

1964 ◽  
Vol 2 (1) ◽  
pp. 117-118
Author(s):  
William A. Hance
Keyword(s):  
Annual Meeting ◽  
West Coast ◽  
Second Generation ◽  
African Studies ◽  
The West ◽  
Academic Society ◽  
American Academic

The sixth annual meeting of the African Studies Association, the leading American academic society of specialists on Africa, was the first to be held on the west coast. Although attendance could not be expected to match that at meetings in the east, a registration of over 250 testifies to the increasing strength of African studies in America. Quite a few of the founders of the Association were present, but the participation of many newcomers suggested that a second generation of American Africanists was bringing new vigour and insights to the field. Several visiting African scholars made notable contributions to the meeting.

Rapid heating of carbonaceous matter by igneous intrusions in carbon-rich shale, Isle of Skye, Scotland: an analogue for heating of carbon in impact craters?

2006 ◽  
Vol 5 (4) ◽  
pp. 343-351 ◽  
Author(s):  
Paula Lindgren ◽  
John Parnell
Keyword(s):  
Organic Matter ◽  
High Temperature ◽  
High Temperatures ◽  
Rapid Heating ◽  
Igneous Intrusion ◽  
High Temperature Process ◽  
Igneous Intrusions ◽  
Life Impact ◽  
Impact Events ◽  
Isle Of Skye

The response of organic matter to high-temperature events is important to astrobiology, as it governs the survival of carbon during several processes that may be critical to the origin and spread of life. Impact cratering is a widespread high-temperature process. The behaviour of carbon during impact events is not well understood. But there is the potential to examine other examples of the response of organic matter to high-temperature processes in the terrestrial geological record. In this study, we report on the interaction of Tertiary igneous intrusions (dolerite sills) and carbon-rich Jurassic mudrocks on the Isle of Skye, Scotland. Despite the high temperatures of the igneous intrusion, carbon has been preserved at the dolerite–shale contact and in shale enclaves where partial melting of the shale has occurred. Even though the temperatures achieved by igneous intrusion are much lower than during impact events, it is a valuable analogue, because it represents a rapid introduction of high temperatures to a carbon-rich rock.

Maoism and Postmodernism

2015 ◽  
Vol 23 (2) ◽  
pp. 261-272
Author(s):  
Alfred Hornung
Keyword(s):  
United States ◽  
New York ◽  
Image Quality ◽  
21St Century ◽  
Cultural Revolution ◽  
Final Stage ◽  
The United States ◽  
Barack Obama ◽  
The West

In this essay I discuss the emergence of the Mao cult during the Cultural Revolution in China and its appropriation in cultural revolutions in Europe and the United States to show how this image resonated with similar cults of popular icons in the West and lent itself to the formulation of theories and practices of postmodernism. The image quality of these cults facilitated the rise of the Mao-craze in the late 1980s and 1990s when political pop productions of Mao by Chinese artists emerged in New York and were then transplanted to China where they met with transfigurations of Mao’s legacy in the People’s Republic. The final stage of postmodern variations of Mao is reached with the presidency of Barack Obama in 2009 and the merging of the two leaders into Chairman Obamao or Comrade Maobama, which can be read as the end of ideological contrast between the two countries for the sake of creating a system of political interdependence for the 21st century, a postmodern prefiguration of a coming ChinAmerica.

When X doesn’t mark the spot: the intersection of language shift, identity and family language policy

2019 ◽  
Vol 2019 (255) ◽  
pp. 133-158 ◽  
Author(s):  
Cassie Smith-Christmas
Keyword(s):  
Language Policy ◽  
Second Generation ◽  
Language Shift ◽  
Third Generation ◽  
Family Language Policy ◽  
Scottish Gaelic ◽  
The Third ◽  
Family Language ◽  
Language Revitalisation ◽  
Isle Of Skye

Abstract This article discusses the reflexive relationship between language shift and identity in the case of Scottish Gaelic on the Isle of Skye, Scotland, demonstrating how (Fishman, Joshua A. 1991. Reversing language shift. Clevedon: Multilingual Matters.) concept of X versus Y as related to language is problematic in this particular context. The article posits that in many ways, the processes by which Gaelic has been alienated from a sense of Scottish identity at the macrolevel are reproduced at the microlevel and discusses the implications of this in terms of Family Language Policy (FLP). Using a nexus analysis approach, this article focuses on a second-generation member – referred to as “Seumas” (the children’s uncle) – of three generations of a Gaelic-speaking family and discusses how, although Seumas appears to see Gaelic as part of his identity in terms of “family” and “heritage”, other identity orientations often take precedence, ostensibly contributing to his high use of English. The article discusses the possible impact that Seumas’ linguistic practices have on the third generation, as well as the double-edged sword nature of using “identity” as a tool in language revitalisation.

Introduction

2017 ◽  
Author(s):  
Penny McCall Howard
Keyword(s):  
Political Economy ◽  
Social Relations ◽  
West Coast ◽  
The West ◽  
Ethnographic Fieldwork ◽  
Key Aspects ◽  
Market Pressures ◽  
Isle Of Skye

Key aspects of the history, social relations and economy of the west of Scotland, particularly the area around the Isle of Skye and Lochalsh. The market pressures that lead to deaths at sea are outlined, and the book’s labour-centred approach to analysis is introduced. The book’s content is situated in both phenomenological and political economy approaches to anthropological analysis. It is also situated historically in the development of capitalism, waged labour and fisheries on the west coast of Scotland and anthropological studies of Scotland and the sea. Finally, the introduction outlines the details of sea-centered approach to ethnographic fieldwork that the book is based on, and the opportunities and limitations this afforded.

scholarly journals Itinéraires et mutations urbaines dans le Mašriq islamique (ier/viie-iiie/ixe siècles)

Arabica ◽  
2017 ◽  
Vol 64 (2) ◽  
pp. 184-212 ◽  
Author(s):  
Fanny Bessard
Keyword(s):  
Persian Gulf ◽  
The Black Sea ◽  
The Political ◽  
Social Mechanisms ◽  
The West ◽  
Arab Muslim ◽  
Economic Strategies ◽  
The Persian Gulf ◽  
Narrow Belt ◽  
The Impact

In the 1st/7th and the early 2nd/8th centuries, the Arab-Muslim conquest united two immense territories, once separated by a shifting border joining the Black sea to the Persian Gulf. To the East, the Arab-Muslims dominated Central Asia and the long-held Asian empire of the Sassanids that reached as far as the Chinese and Indian borders. To the West, they controlled the southern part of the Eastern and Western Roman empires. In the 2nd/8th century, the area conquered thus formed a narrow belt of lands from the Atlantic to the Chinese borders and from Georgia to Yemen. The Middle East became a converging hub of merchants and commercial goods. The article aims to discuss the political and social mechanisms involved in redrawing the map of the routes in the Mašriq from the early Umayyads in 41/661 to the death of caliph al-Muktafī in 295/908. It investigates the impact the evolution of road networks had on settlement patterns and economic strategies. Au ier/viie et au début du iie/viiie siècle, la conquête arabo-musulmane réunit deux immenses territoires, jusqu’alors séparés par une frontière au tracé mouvant joignant la mer Noire au golfe Persique. À l’Est, les Arabo-musulmans dominent l’Asie centrale et l’ancien empire asiatique des Sassanides jusqu’aux confins chinois, et à l’Ouest, la partie méridionale des empires romains d’Orient et d’Occident. L’espace conquis forme au iie/viiie siècle une étroite ceinture de terres de l’Atlantique aux confins de la Chine et de la Géorgie au Yémen. Dans cet espace immense, jusque-là si divisé, le Proche-Orient devient le pôle de convergence des marchands et des biens. Cette reconfiguration géopolitique du Proche-Orient au début de l’Islam entraîne des changements décisifs. L’enjeu de cet article est d’appréhender par quels mécanismes politiques et sociaux la carte des réseaux routiers du Mašriq a été redessinée entre le début du règne des Omeyyades en 41/661 et le décès du calife al-Muktafī en 295/908. Il s’agit d’explorer quel impact l’évolution des trafics eut sur les dynamiques de peuplement et sur les échanges. This article is in French.

Sediment supply on the West Greenland passive margin: redirection of a large pre-glacial drainage system

2020 ◽  
Vol 177 (6) ◽  
pp. 1149-1160
Author(s):  
Scott Jess ◽  
Alexander L. Peace ◽  
Christian Schiffer
Keyword(s):  
Drainage System ◽  
Sediment Supply ◽  
Passive Margin ◽  
Fluvial System ◽  
The West ◽  
Drainage Systems ◽  
West Greenland ◽  
Igneous Province ◽  
Davis Strait ◽  
Supplementary Material

The Mesozoic–Cenozoic separation of Greenland and North America produced the small oceanic basins of the Labrador Sea and Baffin Bay, connected via a complex transform system through the Davis Strait. During rifting and partial breakup sedimentary basins formed that record the changing regional sediment supply. The onshore and offshore stratigraphy of Central West Greenland outlines the presence of a major fluvial system that existed during the Cretaceous and was later redirected in the Early Cenozoic by the formation of the West Greenland Igneous Province. Hydrological analysis of Greenland's isostatically balanced basement topography outlines two major drainage systems that likely flowed across Greenland prior to the onset of glaciation and emptied into the Sisimiut Basin within the Davis Strait, offshore West Greenland. The course of the northern drainage system suggests that it initially flowed NW into the Cretaceous/Palaeocene Nuussuaq Basin, before being redirected SW around the West Greenland Igneous Province in the Mid-Palaeocene. Moreover, characteristics of these two drainage systems suggest they acted as a single larger fluvial system, prior to the onset of glaciation, that was likely the primary source of sediment across Central West Greenland throughout the Cretaceous and Palaeogene. This scenario provides a greater understanding of the West Greenland margin's late Cenozoic evolution, which differs from previous interpretations that hypothesize a period of considerable post-rift tectonism and uplift. This work highlights the importance of large pre-glacial drainage systems across North Atlantic passive margins and their relevance when studying post-rift stratigraphy in rifted margin settings.Supplementary material: Isostatic modelling, hydrological analysis and chi mapping is available at: https://doi.org/10.6084/m9.figshare.c.5050146

Chapter 5 Laxfordian Intrusive Rocks

2002 ◽  
Vol 26 (1) ◽  
pp. 45-50
Keyword(s):  
Sensu Stricto ◽  
Type Locality ◽  
The Core ◽  
Gneiss Complex ◽  
Igneous Intrusions ◽  
Intrusive Rocks ◽  
Narrow Belt

Igneous intrusions of Palaeoproterozoic age occur within the outcrop of the Loch Maree Group and also within the Archaean gneiss complex, cutting the 'Scourie' dykes. Since they post-date either the dykes or the c. 2.0 Ga Loch Maree Group (LMG), they are considered to be Laxfordian in age. They are broadly granitoid in composition, and fall into three categories: (a) a suite of gneissose granodiorites and tonalites, including the Ard gneiss and Mill na Claise gneiss, which intrude the LMG; (b) thin granite sheets cutting both Archaean basement and 'Scourie' dykes; and (c) granitoid pegmatites.The Ard gneiss sensu stricto (Park 1964) is a gneissose granodioritic to tonalitic body (Fig. 5.1 A) whose outcrop extends from the type locality on the An Ard peninsula [802 751], where it is 600 m wide, southeastwards to Dubh Loch where it narrows to about 150 m. Similar gneisses, which are grouped with the Ard gneiss for convenience, occur in the core of the Mill na Claise fold (the Mill na Claise gneiss), and form a narrow belt along the SW side of the Mill na Claise amphibolite from Shieldaig Lodge to the SW end of Dubh Loch (the Cloiche gneiss) (see map).All these gneisses enclose numerous sheet-like bodies of amphibolite similar to, though coarser than, the amphibolites associated with the LMG metasediments. In the NW, on An Ard peninsula and NE of Lochan Dubh nan Cailleach, these amphibolites form distinct sheets up to 150 m wide. Further SE, at Druim Ruadh [822

scholarly journals Contribuições das geociências à prática de educação ambiental em escola da área rural em Alegrete, RS

2002 ◽  
Vol 24 (24) ◽  
pp. 117
Author(s):  
Jaqueline Flain Moraes ◽  
Edgardo Ramos Medeiros
Keyword(s):  
Environmental Degradation ◽  
Final Stage ◽  
Rio Grande ◽  
Local Problem ◽  
Rio Grande Do Sul ◽  
The West ◽  
Local Residents ◽  
Chemical Products ◽  
The One ◽  
Topographical Maps

The present work describes the physical aspects (geology, geomorphology and other) and of the erosive processes, based on direct observation in the field and in the topographical maps of the area localized in the west of Rio Grande do Sul state, more specifically of the municipal districtis of São Francisco of Assis, Manoel Viana and Alegrete.In consequence of erosion problms, ciliary deforestation and sediments accumulation of drainages, a climate map was elaborated, that associated to the characteristics lithological and of vegetation and other, it allowed to determine adult's areas or smaller fragility to the erosive processes.These data together with the one of relief, drainage vegetation, as well as of use and occupation of the soil, they were plotted in an area maquette. Parallel to the physical observation of the area, they were applied questionnaires to the school community, to collect information to projects of environmental education and, to the local residents in order to diagnose the profile economical partner and main problems, as well as planting techniques, conservation of thesoil, production and use of chemical products, among others.As final stage and principal aim of the work, lectures were supplied at the schools (one of each municipal district). The principal kinds of environmental degradation and possible solutions were approached, giving emphasis to the local problem.

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