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The Creation of Lymescroft School: An Ethnographic Study of Some Aspects of a School Merger
The creation of a new school through the amalgamation of three smaller schools is an imposed change which has an impact upon everyone involved. This ethnographic study of the new 'Lymescroft School’ was carried out by a practising teacher who had taught for many years at one of the merged schools. After presenting an outline of various theories regarding the nature of change and the important concept of 'status passage', the role of teacher-researcher is explored. The main ethnographic work of the thesis consists of the descriptive analyses of a number of discrete status passages and transitional experiences with in the informal culture of the school, undergone by four sets of participants - Fifth Year pupils, Fourth Year pupils, a group of teachers, and two small groups of ancillary staff. All went through multiple formal and informal status passages, many of which involved sex and gender issues, particularly where participants moved from a single-sex to a mixed school. The social interaction which took place within this context is broadly examined, and found to comprise a number of temporally linear transitional stages. A comparative analysis of the data reveals that these stages were structurally similar, and comparable to patterns of change in other areas of society. A substantive theory of transition is formulated, which has wider implications for the formal theory of change. This in turn informs policy with regard to any future similar transitions
Valor patrimonial de las pegmatitas del Cap de Creus
Las pegmatitas graníticas del Cap de Creus constituyen un importante elemento de nuestro
patrimonio geológico, con importantes aportaciones, tanto por su gran variedad mineralógica como por la información científica que aporta su estudio. El campo pegmatítico presenta extensos afloramientos que facilitan su estudio. Este campo pegmatítico, con unos 400 cuerpos, consta de cuatro tipos de pegmatitas, encajadas en rocas metapelíticas: microclínicas (I), de berilo-columbita (II), de berilo-columbita-fosfatos (III) y de tipo albítico (IV).
El grado de evolución de estas pegmatitas aumenta hacia las situadas en zonas más internas, siendo éstas las que contienen una mayor variedad mineral: silicatos, fosfatos, óxidos e hidróxidos (minerales de Nb-Ta, casiterita, gahnita, nigerita, crisoberilo, corindón). Los fosfatos presentan una gran variedad, siendo de la asociación Ca-Fe-Mg-Mn en los tipos menos evolucionados y de Li-Al o Li-Fe-Mn en las más evolucionadas. Algunos fosfatos poco comunes presentes en estas pegmatitas son la herderiderita, berlinita y staneckita.Peer ReviewedPostprint (published version
Nb and REE Distribution in the Monte Verde Carbonatite-Alkaline-Agpaitic Complex (Angola)
The Angolan alkaline-carbonatite complex of Monte Verde has a semi-circular shape and is comprised of a central intrusion of foidolite rocks surrounded by concentrically arranged minor bodies of other alkaline rocks and carbonatite magmatic breccias. This rock association is hosted by fenitized Eburnean granites. Concentric swarms of alkaline dykes of late formation, mostly of nepheline trachyte composition, crosscut the previous units. Most high-field strength elements (HFSE) and rare earth elements (REE) are concentrated in pyrochlore crystals in the carbonatite and alkaline breccias. Magmatic fluornatropyrochlore is replaced and overgrown by five secondary generations of pyrochlore formed during subsolidus stages and have higher Th, REE, Si, U, Sr, Ba, Zr, and Ti contents. The second, third, and fourth pyrochlore generations are associated with late fluids also producing quartz and REE rich minerals; whereas fifth and sixth pyrochlore generations are linked to the fenitization process. On the other hand, minerals of the rinkite, rosenbuschite, wöhlerite, eudialyte groups, as well as loparite-(Ce), occur in accessory amounts in nepheline trachyte, recording low to moderate agpaicity. In addition, minor REE-bearing carbonates, silicates, and phosphates crystallize as late minor secondary minerals into carbonatite breccia and alkaline dykes. In conclusion, the scarcity of HFSE and REE minerals at the Monte Verde carbonatite-alkaline-agpaitic complex suggests low metallogenetic interest and economic potential for the outcrops analysed in this study. However, the potential for buried resources should not be neglected
Subsolidus processes in the Longonjo and Bailundo carbonatites (Angola)
Peer ReviewedPostprint (published version
Styles of Alteration of Ti Oxides of the Kimberlite Groundmass: Implications on the Petrogenesis and Classification of Kimberlites and Similar Rocks
The sequence of replacement in groundmass perovskite and spinel from SK-1 and SK-2 kimberlites (Eastern Dharwar craton, India) has been established. Two types of perovskite occur in the studied Indian kimberlites. Type 1 perovskite is found in the groundmass, crystallized directly from the kimberlite magma, it is light rare-earth elements (LREE)-rich and Fe-poor and its ΔNNO calculated value is from −3.82 to −0.73. The second generation of perovskite (type 2 perovskite) is found replacing groundmass atoll spinel, it was formed from hydrothermal fluids, it is LREE-free and Fe-rich and has very high ΔNNO value (from 1.03 to 10.52). Type 1 groundmass perovskite may be either replaced by anatase or kassite along with aeschynite-(Ce). These differences in the alteration are related to different f(CO2) and f(H2O) conditions. Furthermore, primary perovskite may be strongly altered to secondary minerals, resulting in redistribution of rare-earth elements (REE) and, potentially, U, Pb and Th. Therefore, accurate petrographic and chemical analyses are necessary in order to demonstrate that perovskite is magmatic before proceeding to sort geochronological data by using perovskite. Ti-rich hydrogarnets (12.9 wt %-26.3 wt % TiO2) were produced during spinel replacement by late hydrothermal processes. Therefore, attention must be paid to the position of Ca-Ti-garnets in the mineral sequence and their water content before using them to classify the rock based on their occurrence
Stratigraphy of lower Cambrian and unconformable lower Carboniferous beds from the Valls unit (Catalonian coastal ranges)
The Palaeozoic rocks outcropping around Valls are divided into two stratigraphic units. The boundary between both is an unconformity. The lower unit is composed by nearshore platform sediments and a Lower Cambrian age is indicated according to ichnotaxa content. The upper unit consists of pink nodular limestones and dark limestones, and it is followed by siliciclastic Culm Facies rocks. These limestones contain conodonts of the uppermost Tournaisian at its base (anchoralis-latus Zone) and lower Bashkirian (Namurian B) in the upper part. This condensed carbonate sequence was coeval with the thick siliciclastic Culm sedimentation in the surrounding areas.Consejo Interinstitucional de Ciencia y Tecnología; AMB94-0953-CO2-01Consejo Interinstitucional de Ciencia y Tecnología; DGE-PB95-1047Consejo Interinstitucional de Ciencia y Tecnología; PB98-155
Palynological age constraint of Les Vilelles unit, Catalan Coastal Chain, Spain
The Les Vilelles unit is a detrital sequence exposes at the southwestern margin of the Catalonian Coastal Range, NE Spain, below the Carboniferous turbiditic series. Based on the palynological content, the age of this unit was initially assigned to the Middle-Late Devonian (Eifelian to Famennian). Additional radiolarian and connodont findings were considered to be Early-Middle Mississippian (Tournaisian to early Viséan). This age inconsistency and the broad time interval, especially of the first dating, produce some ambiguity in the regional interpretations of the Les Vilelles unit and the overlying Carboniferous sequence. A palynostratigraphic analysis conducted in a section representative of the Les Vilelles unit has provided an assemblage containing miospores, acritarchs, prasinophyta phycomata and chitinozoan that can be confidently assigned to a latest Frasnian interval, in contact with the Frasnian-Famennian boundary. This dating casts doubt on the radiolarian/connodont age assignment and considerably refines the Middle -Late Devonian age formerly established. This study also includes a systematic section with the description of three newly established miospore species:Dibolisporites coniugatum, Dibolisporites priorato and Rugospora spinosa
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