Relevant bibliographies by topics / Lamproite

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Academic literature on the topic 'Lamproite'

Author: Grafiati
Published: 4 June 2021
Last updated: 15 June 2025

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Journal articles on the topic "Lamproite"

1

Chalapati Rao, N. V., and V. Madhavan. "Some Observations on the Geochemistry of Ramannapeta-Ustapalle Lamproitic Body, Krishna District, Andhra Pradesh." Journal Geological Society of India 47, no. 4 (1996): 409–18. http://dx.doi.org/10.17491/jgsi/1996/470403.

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Abstract Detailed petological and geochemical studies pertaining to the lamproitic body recorded by the Geological Survey of India at Ramannapeta-Ustapalle, Krishna district, Andhra Pradesh, are presented. Unmistakable lamproite signatures like the presence of Ti-rich potassic richterite, abundance of Ti-rich, Al-poor phlogopite and Ca-rich, Al-poor clinopyroxene, absence of primary calcite, paucity of typical kimberlite indicator minerals and the ultra potassic nature are recognised. Major oxide as well as the trace elemental abundances of the body are observed to be similar to those of the Chelima lamproites occurring within the intra-cratonic Cuddapah basin. The available radiometric ages of all the known Indian lamproites and kimberlites are taken into consideration and a mid-Proterozoic lamproite event in the Indian sub-continent is postulated.
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Mitchell, Roger H. "Igneous Rock Associations 26. Lamproites, Exotic Potassic Alkaline Rocks: A Review of their Nomenclature, Characterization and Origins." Geoscience Canada 47, no. 3 (2020): 119–42. http://dx.doi.org/10.12789/geocanj.2020.47.162.

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Lamproite is a rare ultrapotassic alkaline rock of petrological importance as it is considered to be derived from metasomatized lithospheric mantle, and of economic significance, being the host of major diamond deposits. A review of the nomenclature of lamproite results in the recommendation that members of the lamproite petrological clan be named using mineralogical-genetic classifications to distinguish them from other genetically unrelated potassic alkaline rocks, kimberlite, and diverse lamprophyres. The names “Group 2 kimberlite” and “orangeite” must be abandoned as these rock types are varieties of bona fide lamproite restricted to the Kaapvaal Craton. Lamproites exhibit extreme diversity in their mineralogy which ranges from olivine phlogopite lamproite, through phlogopite leucite lamproite and potassic titanian richterite-diopside lamproite, to leucite sanidine lamproite. Diamondiferous olivine lamproites are hybrid rocks extensively contaminated by mantle-derived xenocrystic olivine. Currently, lamproites are divided into cratonic (e.g. Leucite Hills, USA; Baifen, China) and orogenic (Mediterranean) varieties (e.g. Murcia-Almeria, Spain; Afyon, Turkey; Xungba, Tibet). Each cratonic and orogenic lamproite province differs significantly in tectonic setting and Sr–Nd–Pb–Hf isotopic compositions. Isotopic compositions indicate derivation from enriched mantle sources, having long-term low Sm/Nd and high Rb/Sr ratios, relative to bulk earth and depleted asthenospheric mantle. All lamproites are considered, on the basis of their geochemistry, to be derived from ancient mineralogically complex K–Ti–Ba–REE-rich veins, or metasomes, in the lithospheric mantle with, or without, subsequent contributions from recent asthenospheric or subducted components at the time of genesis. Lamproite primary magmas are considered to be relatively silica-rich (~50–60 wt.% SiO2), MgO-poor (3–12 wt.%), and ultrapotassic (~8–12 wt.% K2O) as exemplified by hyalo-phlogopite lamproites from the Leucite Hills (Wyoming) or Smoky Butte (Montana). Brief descriptions are given of the most important phreatomagmatic diamondiferous lamproite vents. The tectonic processes which lead to partial melting of metasomes, and/or initiation of magmatism, are described for examples of cratonic and orogenic lamproites. As each lamproite province differs with respect to its mineralogy, geochemical evolution, and tectonic setting there is no simple or common petrogenetic model for their genesis. Each province must be considered as the unique expression of the times and vagaries of ancient mantle metasomatism, coupled with diverse and complex partial melting processes, together with mixing of younger asthenospheric and lithospheric material, and, in the case of many orogenic lamproites, with Paleogene to Recent subducted material.
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Kaur, Gurmeet, Roger H. Mitchell, and Suhel Ahmed. "Mineralogy of the Vattikod lamproite dykes, Ramadugu lamproite field, Nalgonda District, Telangana: A possible expression of ancient subduction-related alkaline magmatism along Eastern Ghats Mobile Belt, India." Mineralogical Magazine 82, no. 1 (2018): 35–58. http://dx.doi.org/10.1180/minmag.2017.081.045.

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ABSTRACTThe mineralogy of nine recently discovered dykes (VL1:VL8 and VL10) in the vicinity of Vattikod village, Nalgonda district in Telangana State is described. The mineral assemblage present and their compositions are comparable to those of bona fide lamproites in terms of the presence of phlogopite (Ti-rich, Al-poor phlogopite and tetraferriphlogopite); amphiboles (potassic-arfvedsonite, potassic-richterite, potassic-ferro-richterite, potassic-katophorite, Ti-rich potassic-katophorite, Ti-rich potassic-magnesio-katophorite); Al-poor clinopyroxenes; feldspars (K-feldspar, Ba-K-feldspar and Na-feldspar) and spinels (chromite-magnetite and qandilite-ulvöspinel-franklinite). These dykes have undergone diverse and significant degrees of deuteric alteration as shown by the formation of secondary phases such as: titanite, allanite, hydro-zircon, calcite, chlorite, quartz and cryptocrystalline SiO2. On the basis of their respective mineralogy: the VL4 and VL5 dykes are classified as pseudoleucite-phlogopite lamproite; VL2 and VL3 dykes as pseudoleucite-amphibole-lamproite; and VL6, VL7 and VL8 as pseudoleucite-phlogopite-amphibole-lamproite. VL10 is extensively altered but contains fresh euhedral apatite microphenocrysts together with pseudomorphs after leucite and is classified as a pseudoleucite-apatite-(phlogopite?) lamproite. The mineralogy of the Vattikod lamproite dykes is compared with that of the Ramadugu, Somavarigudem and Yacharam lamproite dykes which also occur in the Ramadugu lamproite field. The lamproites from the Eastern Dharwar Craton are considered as being possible expressions of ancient subduction-related alkaline magmatism along the Eastern Ghats mobile belt.
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Jaques, A. Lynton, Frank Brink, and Jiang Chen. "Magmatic haggertyite in olivine lamproites of the West Kimberley region, Western Australia." American Mineralogist 105, no. 11 (2020): 1724–33. http://dx.doi.org/10.2138/am-2020-7456.

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Abstract We report the first occurrence of magmatic haggertyite (BaFe6Ti5MgO19) from the Miocene lamproites of the West Kimberley region of Western Australia. This contrasts with the metasomatic formation reported in an olivine lamproite host at the type locality, Prairie Creek, Arkansas. Haggertyite occurs in the groundmass of a diamondiferous olivine lamproite pipe in the Ellendale field, and within the large zoned Walgidee Hills lamproite where it forms part of an extensive suite of Ba- and K-bearing titanate and Ti-rich silicate minerals. The haggertyite co-exists with chromian spinel, perovskite, and ilmenite in the Ellendale lamproite, and with priderite and perovskite and, in one locality, with priderite, jeppeite, ilmenite, and perovskite, in the Walgidee Hills lamproite. Unlike priderite and perovskite, which are common groundmass phases in the Ellendale olivine lamproites and present throughout the Walgidee Hills lamproite, haggertyite appears restricted in its occurrence and crystallization interval, with sparse ilmenite apparently mostly crystallizing as an alternative phase. In the Walgidee Hills lamproite the haggertyite-bearing assemblage is succeeded by the Ba-titanate assemblage priderite plus jeppeite in the evolved central part of the body. The haggertyite in the main zone of the Walgidee Hills lamproite has an average composition of (Ba0.7K0.3)1.0(Ti5.0Fe2.13+Cr0.1Fe3.82+Mn0.2Mg0.6Na0.1)12O19 and is thus very similar to the original haggertyite described from xenoliths in the Prairie Creek lamproite apart from being poorer in Cr and Ni. Haggertyite in the groundmass of the Ellendale olivine lamproite and the central zone of the Walgidee Hills lamproite, in addition to variations in Mg and Cr, show significant variation in Ti and Fe contents and in calculated Fe3+ and Fe2+. A linear inverse relationship between Ti and Fe, and Ti and Fe3+, indicates that Fe3+ is accommodated by the coupled substitution Ti4+ + Fe2+ ⇆ 2 Fe3+. A marked trend to higher Fe3+ in the haggertyite in Ellendale 9 olivine lamproite is ascribed to increasing oxidation during crystallization, with fO2 estimated from the olivine-spinel thermometer and oxygen barometer at Dlog FMQ = –1 to +3 at temperatures of 790–660 °C. The haggertyite in the central zone of the Walgidee Hills lamproite, in contrast, shows a marked trend to Fe2+ enrichment, which is associated with decreasing Fe in perovskite. This is inferred to indicate formation under more reducing conditions, but sufficiently oxidized to permit Fe3+ in co-existing priderite and jeppeite. Trace-element analysis by LA-ICP-MS shows the Walgidee Hills haggertyite contains minor amounts of Na, Si, Ca, V, Co, Zn, Sr, Zr, Nb, and Pb, and only traces of Al, P, Sc, Rb, REE, Hf, and Ta. Moreover, the haggertyite is preferentially enriched in certain lithophile (Ba, Sr), siderophile (Mn, Fe, Co, Ni), and chalcophile (Zn, Pb) elements relative to co-existing priderite. Haggertyite crystallization appears to be a consequence not only of the very high Ba, Ti, and K contents of the lamproite, but of relatively high-Fe concentrations and low temperatures in evolved olivine lamproite magma with the Fe3+/Fe2+ ratio determined by the prevailing fO2. The new data suggest that haggertyite might also be present but previously unrecognized in the evolved groundmass of other olivine lamproites. Haggertyite is one of an increasing number of new minerals in upper mantle rocks and volcanics derived from the upper mantle hosting large-ion-lithophile and high field strength cations.
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Talukdar, Debojit, N. V. Chalapathi Rao, J. Amal Dev, J. K. Tomson, Alok Kumar, and Ashutosh Pandey. "Palaeoproterozoic Lamproite Pulses from the Eastern Dharwar Craton, Southern India: Some Geodynamic Implications." Journal Of The Geological Society Of India 101, no. 6 (2025): 919–24. https://doi.org/10.17491/jgsi/2025/174184.

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ABSTRACT The cratonic regions of the Indian Shield host numerous Precambrian lamproites. A majority of these lamproites are dated at Mesoproterozoic (1070-1434 Ma) using whole-rock 40Ar-39Ar, zircon U-Pb, and mica K-Ar and Rb-Sr geochronology methods. This paper reports the results of Sm-Nd (apatite) and U-Pb (rutile) geochronology on the lamproites from the Somavarigudem and Gundrapalle from the Ramadugu Lamproite Field, Eastern Dharwar Craton. The polychronous nature of the lamproite emplacement in the Eastern Dharwar Craton is illustrated by their new Palaeoproterozoic (2040±31 Ma and 2002±85 Ma) emplacement ages. We infer that the shorter residence time of these lamproite magmas indicates rapid emplacement and may influence the strategy of diamond prospectivity. The similar geochemical and isotopic signature of the entire Eastern Dharwar Craton lamproites, irrespective of their emplacement ages, indicates that multiple isolated mantle source pods prevailed for a longer duration (from ~2040 Ma to ~1400 Ma). The newly reported emplacement ages of 2000 Ma also align with the Palaeoproterozoic model ages of alkaline magmatism of the Eastern Ghats Mobile Belt and the timing of the Columbia supercontinent amalgamation.
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Kaur, Gurmeet, and Roger H. Mitchell. "Mineralogy of the baotite-bearing Gundrapalli lamproite, Nalgonda district, Telangana, India." Mineralogical Magazine 83, no. 03 (2019): 401–11. http://dx.doi.org/10.1180/mgm.2018.169.

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AbstractWe describe the mineralogy of a lamproite dyke from Gundrapalli village (Nalgonda district), Telangana, India. The dyke consists of a mineral assemblage characteristic of lamproites in terms of the presence of amphiboles (mainly potassic-richterite together with potassic-arfvedsonite, magnesio-riebeckite, Ti-rich potassic-magnesio-arfvedsonite, potassic-magnesio-arfvedsonite, katophorite and potassic-ferri-katophorite), Al-poor pyroxene, phlogopite (Ti-rich, Al-poor), pseudomorphed leucite, spinel (chromite-magnesiochromite), fluorapatite, baryte, titanite, rutile, barytocalcite, calcite, ilmenite, hydro-zircon, baotite, strontianite, allanite, quartz and pyrite. The absence of wadeite and priderite have been compensated for by the presence of baotite, rutile, titanite, baryte and hydro-zircons. The presence of the secondary phases: allanite, hydro-zircon, chlorite, quartz and cryptocrystalline silica, implies that the dyke has undergone deuteric alteration. On the basis of its typomorphic mineralogy the Gundrapalli dyke has been classified as a pseudoleucite-phlogopite-amphibole-lamproite. We report the presence of the rare mineral baotite from this lamproite, the first recognition of baotite from a lamproite in India. The mineralogy of the baotite-bearing Gundrapalli lamproite is analogous to the baotite-bearing Kvaløya lamproite from Troms, Norway.
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Chalapathi Rao, N. V., and V. Madhavan. "Titanium-Rich Phlogopites from the Zangamarajupalle Kimberlitic Rock, Andhra Pradesh, India." Journal Geological Society of India 47, no. 3 (1996): 355–63. http://dx.doi.org/10.17491/jgsi/1996/470308.

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Abstract Electron probe studies on the phlogopites from the Zangamarajupalle kimberlitic rock (14°76'7" : 78°88'3" E) in the Proterozoic Cuddapah basin, Andhra Pradesh, reveal their titanium rich (6 wt%) nature - a character typical of lamproite micas. The compositions and their systematic variation in the phlogopite micas of the Zangamarajupalle-kimberlitic rock are compared and contrasted with those of other kimberlitic and lamproitic rocks including pipe-2 Wajrakarur, pipeS (Muligiripalle) and Maddur (Mahbubnagar) - all of which have an ambiguous identity. The utility of phlogopite compositions in discriminating between kimberlites and lamproites is emphasised and an attempt is made to classify the studied rock types accordingly and the implications are discussed.
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AKAL, CÜNEYT. "K-richterite–olivine–phlogopite–diopside–sanidine lamproites from the Afyon volcanic province, Turkey." Geological Magazine 145, no. 4 (2008): 570–85. http://dx.doi.org/10.1017/s0016756808004536.

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AbstractMiddle Miocene volcanic activity in the Afyon volcanic province (eastern part of Western Anatolia) is characterized by multistage potassic and ultrapotassic alkaline volcanic successions. The volcanism is generally related to the northward subduction of the African plate beneath the Eurasian Plate. In Afyon, the Middle Miocene volcanic products consist of melilite leucitite, tephriphonolite, trachyte, basaltic–trachyandesite, phonolite, phonotephrite, tephriphonolite and lamproite rocks. Near-surface emplacement and relatively quiescent subaerial eruptions of lamproitic magma produced different emplacement forms such as dome/plug-shaped bodies and lava flows, showing variation in volume and texture. The mineralogical constituents of the lamproites are sanidine, olivine (77 < Mg no. < 81), phlogopite (74 < Mg no. < 78), K-richterite, clinopyroxene (74 < Mg no. < 78), with accessory apatite, calcite and opaque minerals. Afyon lamproites resemble Mediterranean-type Si-rich lamproites. Their compositional range is 50–52 wt% SiO2, 4–8 wt% MgO, and they display a typical lamproitic affinity. Chondrite-normalized REE patterns exhibit enrichment in LREE relative to HREE ((La/Yb)CN=15.3–17.0). They show extreme enrichment in LILE relative to primitive mantle values and troughs of Nb and Ti. The lamproites give a range of high initial87Sr/86Sr ratios and low143Nd/144Nd ratios. The geochemical and isotopic characteristics suggest that lamproitic magma is derived from highly metasomatized mantle. The enrichment history may include metasomatic events related to subduction, as in other active orogenic areas of the Mediterranean.
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P., Ramesh Chandra Phani, and Srinivas M. "Calcrete Geochemistry in identifying Kimberlite Lamproite Exploration Targets A case study from Nalgonda district, Telangana, southern India." International Journal of Trend in Scientific Research and Development 2, no. 2 (2018): 964–73. https://doi.org/10.31142/ijtsrd9575.

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The pedogenic carbonates, found mainly in arid and semi arid regions of the world, are commonly referred to as calcretes or caliche or kankar. These are authigenic carbonate products which occur in association with soil, forming the residual regolith. Many rock types can produce calcretes upon weathering and denudation, but calcrete derived from certain rocks like kimberlite lamproite acts as an exploration guide. Calcrete is a prominent sampling medium in diamond rich countries like Australia and South Africa whereas it has not received popularity in the Indian context. Kimberlites being ultrapotassic in nature and owing to the enrichment of olivine and serpentine often produce calcrete duricrust as a capping. Recently more than twenty lamproites have been discovered in the Telangana state by the Geological Survey of India. These occurrences unravel a new panorama that the state has a substantial potential for occurrence of more kimberlite lamproite clan rocks. An attempt has been made here to test the geochemical affinity of calcretes from various locations within Nalgonda district. The geochemical data of calcrete samples of this study has been compared with published geochemical data of lamproites of Ramadugu Field, to understand their geochemical association to kimberlite lamproite. The calcretes are low in SiO2 33.92 45.1 wt , high in K2O 1.07 2.21 wt and CaO 0.78 13.61 wt . When compared to other major elements, MgO displays low concentration. The trace elements are found to be enriched in some of the samples collected in close vicinity of known lamproite occurrences. The samples show high degree of chemical weathering, alteration and compositional variation indices. It is observed that enrichment of elements like Cr, Nb, Ba, Ti, Zr etc. indicates, similar to parent kimberlite lamproite rock, favourable targets for further ground exploration in virgin areas. In the present study, two samples, towards five kilometers northeast of Vattikodu Lamproite Field, possess higher concentrations of Nb 25ppm , Ba 400 ppm , Zr 650 ppm and Ti 3500 ppm which stand out as plausible explorable targets for further ground investigations. Further investigations on these two locations are suggested to ascertain whether or not these two targets unveil new kimberlites lamproite occurrences in the area. P. Ramesh Chandra Phani | M. Srinivas "Calcrete Geochemistry in identifying Kimberlite / Lamproite Exploration Targets -A case study from Nalgonda district, Telangana, southern India" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-2 , February 2018, URL: https://www.ijtsrd.com/papers/ijtsrd9575.pdf
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Foley, Stephen, and Maik Pertermann. "Dynamic Metasomatism Experiments Investigating the Interaction between Migrating Potassic Melt and Garnet Peridotite." Geosciences 11, no. 10 (2021): 432. http://dx.doi.org/10.3390/geosciences11100432.

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Dynamic metasomatism experiments were performed by reacting a lamproite melt with garnet peridotite by drawing melt through the peridotite into a vitreous carbon melt trap, ensuring the flow of melt through the peridotite and facilitating analysis of the melt. Pressure (2–3 GPa) and temperature (1050–1125 °C) conditions were chosen where the lamproite was molten but the peridotite was not. Phlogopite was formed and garnet and orthopyroxene reacted out, resulting in phlogopite wehrlite (2 GPa) and phlogopite harzburgite (3 GPa). Phlogopites in the peridotite have higher Mg/(Mg + Fe) and Cr2O3 and lower TiO2 than in the lamproite due to buffering by peridotite minerals, with Cr2O3 from the elimination of garnet. Compositional trends in phlogopites in the peridotite are similar to those in natural garnet peridotite xenoliths in kimberlites. Changes in melt composition resulting from the reaction show decreased TiO2 and increased Cr2O3 and Mg/(Mg + Fe). The loss of phlogopite components during migration through the peridotite results in low K2O/Na2O and K/Al in melts, indicating that chemical characteristics of lamproites are lost through reaction with peridotite so that emerging melts would be less extreme in composition. This indicates that lamproites are unlikely to be derived from a source rich in peridotite, and more likely originate in a source dominated by phlogopite-rich hydrous pyroxenites. Phlogopites from an experiment in which lamproite and peridotite were intimately mixed before the experiment did not produce the same phlogopite compositions, showing that care must be taken in the design of reaction experiments.
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Dissertations / Theses on the topic "Lamproite"

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Condamine, Pierre. "Rôle du phlogopite sur la genèse de magmas riches en potassium : approche expérimentale." Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22596/document.

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Des liquides riches en K2O ( K2O &gt; 2 pds. % ; K2O/Na2O &gt; 1) sont observés dans la majeure partie des contextes géodynamiques sur Terre. Ces liquides sont principalement caractérisés par leurs teneurs en K2O variant entre 3 et 13 pds. % et des rapports K2O/Na2O de 1 – 40. Les compositions chimiques des différents groupes de liquides riches en K2O observés sont extrêmement variables, depuis des termes très sous-saturés en silice (kamafugites, kimberlites, lamproïtes madupitiques à olivine) à des termes sur-saturés en silice (shoshonites, lamproïtes à phlogopite). Ces fortes teneurs en K2O et les rapports K2O/ Na2O élevés ne peuvent pas être obtenus par la fusion de péridotites fertiles ou réfractaires. Des expériences de fusion partielle en piston-cylindre ont été réalisées sur des péridotites à phlogopite ± amphibole dans les domaines de stabilité du spinelle et du grenat (1 et 3 GPa) afin de déterminer la capacité du manteau lithosphérique à produire des liquides riches en K2O. La présence de faibles teneurs en fluor dans le matériel de départ stabilise le phlogopite à des températures supérieures aux études antérieures. Les faibles degrés de fusion obtenus à 1 GPa sont sur-saturés en silice et leur teneur en K2O est tamponnée à 4 – 6 pds. % par la présence de phlogopite résiduel pour des péridotites fertile et réfractaire, respectivement. Les expériences réalisées à 3 GPa montrent que les premiers degrés de fusion sont sous-saturés en silice mais plus riches en K2O (6 – 8 pds. % pour la lherzolite et la harzburgite, respectivement) que dans le domaine du spinelle, démontrant l’importance de la pression sur la genèse de liquides riches en K2O. Les modélisations réalisées montrent également que l’augmentation de la proportion de phlogopite dans la source ne modifie pas la teneur en K2O des liquides formés mais diminue leurs rapports K2O/Na2O. Par conséquent, la fusion de péridotite à phlogopite dans la gamme de pression étudiée ne permet pas d’obtenir des liquides aussi riches en K2O que certains lamproïtes et kamafugites. Une série d’expériences réalisée sur du phlogopite pur à 1 et 3 GPa montrent que les liquides dérivés de telles sources sont très riches en K2O (12 – 14 pds. %) et comparables aux lamproïtes. Les différentes lithologies dans le manteau ne permettent cependant pas d’expliquer la grande gamme de composition des liquides riches en K2O et nécessitent des conditions riches en éléments volatils (H2O, CO2, F) et des fugacités d’oxygène réductrices<br>K2O-rich melts (K2O &gt; 2 wt. %; K2O/Na2O &gt; 1) have been described in all of the major geodynamic settings on Earth. These melts are mainly characterized by their huge K2O content, ranging between 2 – 13 wt. % and K2O/Na 2 O ratios of 1 – 40. The chemical compositions of the different K2O-rich melt groups span a very high variability, from strongly silica undersaturated melts (kamfugites, kimberlites, madupitic lamproites) to silica-rich terms (shoshonites, phlogopite lamproites). These very high K2O contents together with strong K2O/Na2O ratios cannot be derived from partial melting of fertile or depleted peridotites. Partial melting experiments have been conducted in piston cylinder apparatus on phlogopite ± amphibole-peridotite in the spinel and garnet stability fields (1 – 3 GPa) in order to determine the ability of the lithospheric mantle to produce K2O-rich melts. The presence of small amounts of fluorine in the starting material leads to stabilize phlogopite at higher temperatures than previously determined. The first degrees of melting at 1 GPa are silica-rich and their K2O contents are buffered to 4 – 6 wt. % in the presence of residual phlogopite, depending on the source fertility (lherzolite and harzburgite, respectively). In the garnet stability field at 3 GPa, low-degree melts are silica-undersaturated but are enriched in K2O, compared to the garnet stability field: from 6 to 8 wt. % in lherzolite and harzburgite sources, respectively. These results suggest that pressure is a key parameter in the mantle to produce K2O-rich melts. Partition coefficient modelings show that increasing the phlogopite proportion in the mantle source does not modify the K2O content of derived melts, but decreases their K2O/Na2O ratios. Consequently, partial melting of phlogopite-peridotite in this range of pressure cannot accounts for the highest K2O contents observed in natural lamproites and kamafugites. A series of experiments has been realized on pure phlogopite at 1 and 3 GPa, showing that derived melts are strongly enriched in K2O (12 – 14 wt. %) and share chemical affinities with lamproites. Peridotite or pyroxenite melting in the presence of phlogopite, however, do not permit to reproduce the high chemical variability of natural K2O-rich melts requires volatile-rich conditions (H2O, CO2, F) and reduced oxygen fugacities
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2

Eastell, Julie. "A low dilution fusion technique for the determination of major, minor and trace elements in Lamproite and Kimberlite samples by X-ray fluorescence spectrometry." Master's thesis, University of Cape Town, 1986. http://hdl.handle.net/11427/21888.

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Bibliography: pages 200-204.<br>A low dilution fusion technique using a 2:1 flux:sample ratio has been developed for the accurate determination of major, minor and trace elements by x-ray fluorescence spectrometry (XRFS). This method has been used to analyze geological samples of widely varying and unusual composition such as lamproites and kimberlites. The results are shown to be of comparable if not better accuracy than other methods of sample preparation for XRFS. Analytical conditions, including corrections for spectral line interferences are reported for all the elements determined. For major element analysis three methods of calculating appropriate alpha coefficients were investigated, namely (1) multiple regression analysis, (2) Norrish and Hutton method and (3) a computer program, NBSGSC, involving fundamental parameters and the COLA equation. Methods (1) and (2) gave poor results for rock types of widely varying composition. The third method requires that the variation of alpha coefficients with varying weight fraction of the analyte element be taken into account when calculating alpha coefficients if accurate values for major and minor elements are to be obtained on low dilution fusion discs. For trace element analysis the average relative error was less than 5% and there was a decrease in sensitivity by about a factor of 2 compared with XRFS determinations on powder pellets. The elimination of particle size effects in the homogeneous glass fusion discs is a major advantage over the use of powder pellets, especially for the determination of elements such as Ba, Cr and the REEs. A loss on fusion technique has been employed to ensure complete loss of volatiles from the rock samples. Data presented highlight the problems encountered in the determination of the volatile content in geological samples. The oxidation and retention of sulphur in the discs was also investigated.
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Silva, Simone da. "Petrografia e química mineral das intrusões Indaiá I e Indaiá II, oeste do Estado de Minas Gerais." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/44/44143/tde-15082008-145504/.

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A presente dissertação se ocupou da investigação petrográfica e química mineral de rochas ultramáficas, potássica-ultrapotássicas, insaturadas em sílica, de afinidade kimberlítica, das intrusões Indaiá I e Indaiá II, oeste do Estado de Minas Gerais. Estas rochas afloram na Província Ígnea do Alto Paranaíba (PIAP, Cretáceo Superior), dentro de uma área alongada segundo N30W, perfazendo aproximadamente 250 km de extensão e 70 km de largura. As suítes do PIAP encontram-se à margem oeste do Cráton do São Francisco, alojadas em litologias pertencentes próprio Cráton e à Faixa Brasília. Os dados petrográficos, dentro das suas limitações, principalmente no que tange à sobreposição de características entre as rochas dos clãs kimberlitos, lamproítos, kamafugitos, orangeitos e lamprófiros, denotam na intrusão Indaiá I a presença de texturas porfiríticas, compostas de mega e fenocristais anédricos a subédricos de olivina, opacos e mais raramente de enstatita, fixados em matriz afanítica formada de cristais anédricos de olivina (crisolitaforsterita), minerais opacos, monticellita tabular, cristais amarronzados subédricos de perovskita, clinopiroxênio (diopsídio) esverdeado e carbonatos. Já na intrusão II se observa a presença de fenocristais anédricos a subédricos de olivina, fixados em matriz afanítica contendo alguns microfenocristais, prismáticos a subédricos, de clinopiroxênio diopsídico esverdeado, cristais anédricos de minerais opacos associados a espinélio avermelhado, cristais subédricos a anédricos de perovskita, grãos arredondados de olivina e também raro vidro intersticial, embora já devidrificado. A composição mineral observada nas rochas da intrusão Indaiá I é representada essencialmente por cristais de crisolita - forsterita (Mg/Mg+Fe2+ de 83 a 95), enstatita (En85,3Fs12,7Wo1,54), ilmenita magnesiana, Cr-espinélio representados por espinélio e membros da série chromite-magnetite-ulvöspinélio, monticellita (92% do membro final CaMgSiO4 ) e perovskita (93% do membro final CaTiO3). Na intrusão Indaiá II, a assembléia mineral presente é bastante similar à observada na intrusão I, contudo com um piroxênio diopsídico mais enriquecido em cálcio (En39,7Fs10,2Wo48,0) e ausência de minerais espinélio e monticellita. Com base na conjunção das características petrográficas e químicas dos minerais descritas no presente trabalho, propõe-se para as rochas das duas intrusões uma afinidade kimberlítica, pertencente ao clã dos kimberlitos do Grupo I. Apesar das ilmenitas magnesianas possuirem composições indicativas de que o líquido gerador das rochas favorece a preservação de diamantes, posto a inexistência de macrocristais de cromita com alta porcentagem de Cr2O3 e granadas G10 e/ou eclogitícas com altos teores de Na2O, a propensão à mineralização é frustada, isto porque, aparentemente, estas intrusões não amostraram xenólitos e macrocristais situados dentro da região do campo de estabilidade dos diamantes. As rochas de Indaiá I e Indaiá II apresentam uma assembléia mineral com possibilidades de existência de diamantes. As ilmenitas magnesianas presentes nessas rochas possuem uma composição indicativa de um ambiente gerador favorável à preservação de diamantes. Entretanto, a inexistência de macrocristais de cromita com alta porcentagem de Cr2O3 e de granadas do tipo G10 e/ou eclogitícas com altos teores de Na2O frusta essa propensão à mineralização. Isto porque, estas intrusões aparentemente não amostraram xenólitos e macrocristais de alta pressão situados dentro da região do campo de estabilidade dos diamantes no manto.<br>An integrated petrographic and mineral chemistry study has been carried out on ultramafic, potassic to ultrapotassic and silica-undersaturated rocks of kimberlitic affinity of the Indaiá I and Indaiá II intrusions, Western Minas Gerais State, Brazil. These rocks outcrop at the Alto Paranaíba Igneous Province (PIAP), within a N30W-trending, elongated area, which is 250-km long and 70-km wide. The PIAP suites are located on the western border of the São Francisco Craton and are emplaced in a basement composed of rocks from the Craton itself and late Proterozoic Brasília fold belt. Within the limitations imposed by the overlapping mineralogical characteristics of the kimberlite, lamproite, kamafugite, orangeite and lamprophyre clans, petrographic data show differences in the Indaiá I and II mineralogical compositions. Indaiá I consists of olivine, opaque mineral and orthopyroxene megacrysts and phenocrysts set in an aphanitic groundmass of olivine, opaque minerals, tabular monticellite, subeuhedral brown perovskite, green diopside and carbonates, whereas Indaiá II comprises anhedral to subeuhedral olivine phenocrysts set in an aphanitic matrix of prismatic to subeuhedral greenish diopside microphenocrysts, anhedral opaque minerals and related brownish spinel, perovskite, rounded olivine and occasional interstitial (devitrified) glass. The Indaiá I mineral chemistry comprises chrysolite to forsterite [83 < Mg/(Mg+Fe2+) < 95], enstatite (En85.3Fs12.7Wo1.54), magnesian ilmenite, Cr-bearing spinels from spinel to chromite-magnetite-ulvöspinel members, monticellite (92 mol% CaMgSiO4 end-member), and perovskite (93 mol% CaTiO3 end-member). Indaiá II is similar to Indaiá I, except for the slightly Ca-enriched diopsidic clinopyroxene (En39.7Fs10.2Wo48.0), and the lack of spinels and monticellite. On the basis of petrographic characteristics and mineral chemistry, it is proposed that the rocks from both Indaiá I and II belong to the Group I kimberlites. Both the intrusions are similar to many Group I kimberlites of the world and comprise some minerals that indicate the possible presence of diamonds, such as the magnesian ilmenite, whose composition reflects generation conditions to preserve diamonds. However, the generalized lack of chromite macrocrysts with high Cr2O3 contents and G10 and/or eclogitic garnets with high Na2O contents attests for the lack of diamonds, once these intrusions have not sampled highpressure xenoliths and macrocrysts within the diamond stability field in the mantle.
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Downes, Peter. "Magmatic evolution, xenolith mineralogy, and emplacement history of the Aries micaceous kimberlite, central Kimberley Basin, Western Australia." University of Western Australia. School of Earth and Geographical Sciences, 2006. http://theses.library.uwa.edu.au/adt-WU2007.0030.

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<Truncated abstract> The Neoproterozoic (815.4 ± 4.3 Ma) Aries kimberlite intrudes the King Leopold Sandstone and the Carson Volcanics in the central Kimberley Basin, northern Western Australia. Aries is comprised of a N-NNE-trending series of three diatremes and associated hypabyssal kimberlite dykes and plugs. The diatremes are volumetrically dominated by massive, clast-supported, accidental lithic-rich kimberlite breccias that were intruded by hypabyssal macrocrystic phlogopite kimberlite dykes and plugs with variably uniform- to globular segregationary-textured groundmasses. Lower diatremefacies, accidental lithic-rich breccias probably formed through fall-back of debris into the vent with a major contribution from the collapse of the vent walls. These massive breccias are overlain by a sequence of bedded volcaniclastic breccias in the upper part of the north lobe diatreme. Abundant, poorly-vesicular to nonvesicular, juvenile kimberlite ash and lapilli, with morphologies that are indicative of phreatomagmatic fragmentation processes, occur in a reversely-graded volcaniclastic kimberlite breccia unit at the base of this sequence. This unit and overlying bedded accidental lithic-rich breccias are interpreted to be sediment gravity-flow deposits (including possible debris flows) derived from the collapse of the crater walls and/or tephra ring deposits that surrounded the crater. ... This Fe-enrichment may have resulted from Fe-Mg exchange with olivine during slow cooling of the peridotite host rocks. Textures reflecting the cooling history of some mantle xenoliths are preserved in the form of fine exsolution rods of aluminous spinel in diopside and zircon in rutile grains in aluminous spinel- and rutile-bearing serpentinised ultramafic xenoliths, respectively. These textures suggest nearly isobaric cooling of host rocks in the lithospheric mantle, and indicate that at least some aluminous spinel in spinel-facies peridotites formed through exsolution from chromian 4 diopside. Episodes of Fe-Ti-rich metasomatism in the spinel-facies Kimberley mantle are the likely source of high-Ti phlogopite-biotite + rutile and Ti, V, Zn, Ni-enriched aluminous spinel ± ilmenite associations in several ultramafic xenoliths. U-Pb SHRIMP 207Pb/206Pb zircon ages for one granite (1851 ± 10 Ma) and two serpentinised ultramafic xenoliths (1845 ± 30 Ma; 1861 ± 31 Ma) indicate that the granitic basement and lower crust beneath the central Kimberley Basin are at least Palaeoproterozoic in age. However, Hf-isotope analyses of the zircons in the ultramafic xenoliths suggest that the underlying lithospheric mantle is at least late Archaean in age.
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Wagner, Christiane. "Contributions à l'étude minéralogique et géochimique des roches hyperalcalines potassiques : lamproites et roches voisines." Paris 6, 1987. http://www.theses.fr/1987PA066220.

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Decanter, Nolwenn. "Divergence génomique et spéciation entre la lamproie de rivière - parasite (Lampetra fluviatilis) et la lamproie de Planer - non-parasite (L. planeri)." Electronic Thesis or Diss., Rennes, Agrocampus Ouest, 2023. http://www.theses.fr/2023NSARA093.

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L’isolement reproducteur est une question clé dans l’étude de la spéciation. Nous avons étudié les mécanismes de l’isolement reproducteur entre deux espèces proches de lamproies. La lamproie de rivière Lampetra fluviatilis (LF) est anadrome et parasite alors que la lamproie de Planer L. planeri (LP) est résidente en eau douce et non parasite. Malgré des histoires de vie différentes, les deux espèces utilisent les mêmes habitats de reproduction, peuvent s’hybrider et sont considérées comme des écotypes avec un isolement reproducteur partiel. Grâce à de précédents travaux, nous savons que la première génération d’hybrides est viable et des marqueurs génétiques permettent de différentier les deux écotypes. Jusqu’ici, peu d’hybrides de seconde génération ou de rétrocroisements ont été identifiés. Ces hybrides pourraient avoir une valeur sélective moins importante, ce qui expliquerait le flux de gènes limité et le maintien des deux écotypes.Néanmoins, une analyse de l’hybridation sur plus de 1000 individus d’une même population a montré que la majorité des individus étaient hybrides avec environ 40% de F1s. A l’échelle du génome, deux régions semblent concentrer la majorité des différences entre LP et LF. Les différences structurales ainsi que les gènes présents dans ces régions ont été identifiés. En outre, des expériences de compétition spermatique n’ont révélé aucune barrière prézygotique malgré des différences de qualité spermatique entre les mâles LP et LF. En conclusion, il semble que l’intensité des barrières à la reproduction entre LF et LP soit faible, en lien avec une divergence génétique concentrée dans deux régions du génome<br>Reproductive isolation is a key issue in the study of speciation. Here, we investigated the mechanisms of reproductive isolation between two closely related lamprey species. The river lamprey Lampetra fluviatilis (LF) is anadromous and parasitic of other fish species whereas the brook lamprey L. planeri (LP) is freshwater resident and non-parasitic. Despite different life histories, the two species use the same breeding habitats, can hybridize and are considered as partially reproductively isolated ecotypes. From previous studies, we know that first- generation hybrids (F1) are viable and molecular markers allow the distinction of both ecotypes.So far, few second-generation hybrids (F2) or backcrosses (F1xF0) have been identified. Such hybrids may have a lower fitness, which could explain the limited gene flow and maintenance of the two ecotypes. However, an analysis of hybridization in 1000 individuals from a single population revealed that most individuals were hybrids including about 40% of F1s. At the genome scale, two regions of the genome seem to concentrate the majority of differences between LP and LF. Structural differences as well as the genes present in those regions were identified. Sperm competition experiments revealed no prezygotic post-mating barrier even though sperm quality differs between LP and LF males. To conclude, it seems that the intensity of reproductive barriers between LF and LP is low, in relation with a genetic divergence concentrated in two regions of the genome
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Davy, Andrew Timothy. "The size distributions of diamonds in kimberlites and lamproites." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47405.

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Pflieger, Jean-François. "Organisation du système vestibulaire chez la lamproie, Petromyzon marinus." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0017/NQ47635.pdf.

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Rougemont, Quentin. "Évolution de la divergence entre la lamproie fluviatile (Lampetra fluviatilis) et la lamproie deplaner (Lampetra planeri) inférée par approches expérimentales et de génomique des populations." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S141/document.

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Cette thèse étudie le processus de spéciation entre la lamproie fluviatile (Lampetra fluviatilis) et la lamproie de Planer (L. planeri). Les deux espèces présentent des stratégies d'histoire de vie extrêmement différentes : L. fluviatilis est parasite et anadrome alors que L. planeri n'est pas parasite et reste strictement dulcicole. Toutefois, leur degré d'isolement reproducteur et leur histoire de divergence demeurent méconnus. Ces questions ont été abordées par des approches expérimentales, de génomique de populations et de simulations démographiques. Des croisements expérimentaux ont révélé un faible isolement reproducteur, confirmé par des degrés variables de flux géniques dans les populations naturelles. Les analyses génétiques ont montré que les deux taxons représentaient probablement des écotypes avec un isolement reproducteur partiel suggérant que les barrières reproductives endogènes ne réduisaient que partiellement la migration efficace entre écotypes. L'importance du contexte géographique actuel et passé dans l'étude de la spéciation a aussi été mise en évidence par des analyses à l'échelle du génome. Ainsi, les populations isolées de L. planeri évoluent principalement sous l'effet de la dérive génétique et ont une diversité réduite. Les inférences démographiques ont suggéré que la divergence a été initiée en allopatrie puis suivie de contacts secondaires résultant en un parallélisme génomique partiel entre réplicas de paires de populations. Une hétérogénéité de la divergence génomique a démontré que les ilots génomiques de différenciation ne résultaient pas de l'action récente de la divergence écologique. En outre, nos résultats suggèrent un impact faible de la fragmentation anthropique des cours d'eau sur la diversité génétique des populations de L. planeri. Les populations résidentes possèdent une diversité génétique plus grande lorsque le flux de gènes avec L. fluviatilis dans les parties aval des cours d'eau. Globalement cette thèse a démontré que les paires d'écotypes parasites et non-parasites de lamproies représentent un excellent modèle d'étude de la spéciation et notamment de l'architecture génomique de la divergence<br>This thesis investigates the process of speciation between the European lampreys Lampetra fluviatilis and L. planeri. The two species have drastically different life history strategies: L. fluviatilis is parasitic and anadromous while L. planeri is non-parasitic and strictly freshwater resident. Yet their level of reproductive isolation and history of divergence remain poorly understood. A multidisciplinary approach including experiments, population genomics analyses and historical reconstruction was undertaken to address these issues. Experimental crosses revealed a very low level of reproductive isolation, partially mirrored by variable levels of gene flow in wild populations. Genetic analyses revealed that the two taxa were best described as partially reproductively isolated ecotypes suggesting that endogenous genetic barriers partially reduced effective migration between ecotypes. Genome wide analyses showed the importance of the current and ancient geographical context of speciation. In particular, parapatric L. planeri populations diverged mostly through drift and displayed a reduced genetic diversity . Demographic inferences suggested that divergence have likely emerged in allopatry and then secondary contacts resulted in partial parallelism between replicate population pairs. A strong heterogeneity of divergence across the genome was revealed by sympatric populations suggesting that genomic islands of differentiation were not linked to ongoing ecological divergence. Further investigations showed that the genetic diversity of L. planeri populations was weakly affected by human-induced river fragmentation. Resident populations displayed a higher diversity when gene flow was possible with L. fluviatilis populations in downstream sections of rivers. Overall this thesis showed that parasitic and non-parasitic lamprey ecotypes represent a promising model for studying speciation and notably the genomic architecture of divergence
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Lagadec, Ronan. "Mécanismes de latéralisation de l'épithalamus chez la lamproie et la roussette." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066423/document.

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Les vertébrés font partie des animaux à symétrie bilatérale mais celle-ci n'est pas parfaite et de nombreuses asymétries sont visibles entre les côtés gauche et droit, notamment au niveau du système nerveux. L'épithalamus s'est imposé comme le modèle de référence pour l'étude des mécanismes de latéralisation du cerveau. Cette structure dérivée du diencéphale dorsal se compose de deux noyaux bilatéraux, les habénulæ et du complexe pinéal, qui regroupe les glandes pinéale et parapinéale. Les habénulæ présentent des asymétries plus ou moins marquées chez tous les grands groupes de vertébrés. La parapinéale est également asymétrique mais elle est absente dans de nombreux taxa. Chez le poisson zèbre, espèce modèle de référence pour l'étude des mécanismes de formation des asymétries épithalamiques, une migration latéralisée de la parapinéale est nécessaire à l'élaboration des asymétries habénulaires. Les mécanismes génétiques sous-jacents ont également été en partie décryptés. La première asymétrie visible dans le diencéphale dorsal correspond à une activité de la voie de signalisation Nodal à gauche. Si cette voie Nodal est essentielle pour induire une asymétrie neurogénétique précoce, elle ne l'est pas pour la formation des asymétries épithalamiques définitives. Son rôle se restreint à biaiser la directionnalité des asymétries en influençant la migration de la parapinéale. Les asymétries habénulaires sont induites par la position finale de la parapinéale. La conservation à l'échelle des vertébrés des mécanismes décrits chez le poisson-zèbre reste une question ouverte. Au cours de ce travail de thèse, j’ai cherché à comprendre l’évolution de ces mécanismes en étudiant un chondrichtyen, la roussette Scyliorhinus canicula et des cyclostomes, les lamproies Petromyzon marinus et Lampetra planeri. Leur position phylogénétique ainsi que les asymétries majeures en taille observées entre les habénulæ gauche et droite font de ces espèces de bons modèles pour comprendre leur origine chez les vertébrés. Mes travaux conduisent à trois conclusions principales :(1) on retrouve, comme chez le poisson zèbre, une expression asymétrique de la voie Nodal dans le diencéphale dorsal gauche de la lamproie et de la roussette; la directionnalité de cette asymétrie est conservée entre les trois espèces, ce qui permet d’exclure une inversion de latéralité précédemment proposée chez la lamproie sur la base d’arguments de taille relative des habénulæ(2) La voie Nodal est essentielle à la formation des asymétries habénulaires chez la roussette et la lamproie, ce qui suggère un rôle ancestral dans l’élaboration des asymétries épithalamiques.(3) une analyse détaillée des patrons de prolifération-différenciation des habénulæ au cours du développement de la roussette met en évidence des asymétries moléculaires et cellulaires multiples ; elle démontre en particulier l’existence d’une neurogenèse asymétrique qui débute plus précocement à gauche. Ces travaux donnent un éclairage nouveau sur l’origine et la diversification des mécanismes contrôlant la formation des asymétries cérébrales chez les vertébrés. L’étude de la roussette et la lamproie, deux organismes modèles non conventionnels, ouvrent de nouvelles perspectives pour leur compréhension<br>Vertebrates are part of the bilaterally symmetric animals but this one is not perfect and numerous asymmetries can be seen between the left and right sides, especially in the nervous system. The epithalamus has proven itself to be the model system for brain lateralization mechanisms’ studies. This structure derived from the dorsal diencephalon contains by the bilaterally paired habenular nuclei and the pineal complex, which includes the pineal gland and parapineal organ. The habenulae exhibit more or less marked left-right asymmetries among most of the major vertebrate taxa. The parapineal is also asymmetrical but it is absent in many taxa. Zebrafish is the model system for the studies of the developmental mechanisms of epithalamic asymmetries. In this species, a lateralized parapineal migration is required for the establishment of habenular asymmetries. The underlying genetic mechanisms have also been partially decrypted. The first conspicuous asymmetry in the dorsal diencephalon corresponds to a left-sided expression of components of the Nodal signalling pathway. This asymmetric Nodal signalling activity is essential to induce an early neurogenetic asymmetry but not necessary the formation of epithalamic asymmetries per se. Its role is restricted to provide a bias to the parapineal organ’s lateralized migration, and thus influence the laterality of epithalamic asymmetries. Indeed, habenular asymmetries are induced by the final position of the parapineal organ. Conservation of these mechanisms described in zebrafish across vertebrates remains an open question. During this thesis, I tried to understand the evolution of these mechanisms by studying a Chondrichthyes, the catshark Scyliorhinus canicula and cyclostomes, the lampreys Petromyzon marinus and Lampetra planeri. Their phylogenetic position and the major asymmetries in size observed between their left and right habenulae make these species good model systems to understand the origin of these mechanisms in vertebrates. My work leads to three main conclusions:(1) As in zebrafish, we have found an asymmetric expression of the components of the Nodal signalling pathway in the left dorsal diencephalon of the catshark and the lamprey. The laterality of the asymmetry is conserved between these three species, which allows us to exclude a reversed laterality in lampreys like it was proposed on the basis of arguments related to the size of habenular nuclei.(2) The Nodal signalling pathway is requied for the establishment of habenular asymmetries in the catshark and lamprey thus suggesting an ancestral role in the development of epithalamic asymmetries.(3) A detailed analysis of proliferation-differentiation patterns in the catshark habenulae during their development highlighted multiple cellular and molecular asymmetries. In particular it showed the existence of an earlier left-sided asymmetric neurogenesis.These studies provide new insights about the origin and diversification of the mechanisms controlling the establishment of vertebrates’ brain asymmetries. The study of the lamprey and the dogfish, two unconventional model systems open new perspectives for their understanding
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Books on the topic "Lamproite"

1

Jaques, A. L. The kimberlites and lamproites of Western Australia. G.P.O., 1986.

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Alekseevich, Bogatikov Oleg, Kononova V. A, and Institut geologii rudnykh mestorozhdeniĭ, petrografii, mineralogii i geokhimii (Akademii͡a︡ nauk SSSR), eds. Lamproity. Nauka, 1991.

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International, Kimberlite Conference (4th 1986 Perth Western Australia). Post-conference field excursion guide to the lamproites of the Kimberley Region, Western Australia. s.n., 1987.

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W. Dan Hausel. Diamonds & Mantle Source Rocks in the Wyoming Craton: With a Discussion of Other US Occurrences. Wyoming State Geological Survey, 1998.

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W. Dan Hausel. Geology and geochemistry of the Leucite Hills volcanic field. Wyoming State Geological Survey, 2006.

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Mitchell, Roger H. Kimberlites, orangeites, and related rocks. Plenum Press, 1995.

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Mitchell, Roger H. Petrology of lamproites. Plenum Press, 1991.

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Dunne, Kathryn P. E., 1963-, Grant Brian 1946-, Geological Association of Canada, Mineralogical Association of Canada, and Mid-Continent Diamonds Symposium (1993 : Edmonton, Alta.), eds. Mid-continent diamonds: GAC-MAC Symposium volume, Edmonton, Alberta, May 17-18, 1993. Mineral Deposit Research Unit, The University of British Columbia, 1993.

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Mitchell, Roger H., and Steven C. Bergman. Petrology of Lamproites. Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-3788-5.

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Lampronti, Galleria Cesare. Galleria Cesare Lampronti: Maastricht 2005. Galleria Cesare Lampronti, 2005.

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Book chapters on the topic "Lamproite"

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Mitchell, Roger H., and Steven C. Bergman. "The Lamproite Clan." In Petrology of Lamproites. Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-3788-5_1.

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Mitchell, Roger H., and Steven C. Bergman. "Description of Lamproite Occurrences." In Petrology of Lamproites. Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-3788-5_3.

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Hearn, B. Carter. "Smoky Butte lamproite, Montana." In Montana High-Potassimn Igneous Province: Crazy Mountains to Jordan, Montana. American Geophysical Union, 1989. http://dx.doi.org/10.1029/ft346p0075.

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Mitchell, Roger H., and Steven C. Bergman. "Tectonic Framework of Lamproite Genesis." In Petrology of Lamproites. Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-3788-5_4.

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Sahu, N., T. Gupta, S. C. Patel, et al. "Petrology of Lamproites from the Nuapada Lamproite Field, Bastar Craton, India." In Proceedings of 10th International Kimberlite Conference. Springer India, 2013. http://dx.doi.org/10.1007/978-81-322-1170-9_9.

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Mitchell, Roger H., and Steven C. Bergman. "Potassic Rocks and the Lamproite Clan." In Petrology of Lamproites. Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-3788-5_2.

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Mitchell, Roger H., and Steven C. Bergman. "Petrological Facies and Igneous Forms of the Lamproite Clan." In Petrology of Lamproites. Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-3788-5_5.

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Mitchell, Roger H., and Steven C. Bergman. "Petrogenesis of Lamproites." In Petrology of Lamproites. Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-3788-5_10.

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Mitchell, Roger H., and Steven C. Bergman. "Mineralogy of Lamproites." In Petrology of Lamproites. Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-3788-5_6.

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Mitchell, Roger H., and Steven C. Bergman. "The Geochemistry of Lamproites." In Petrology of Lamproites. Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-3788-5_7.

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Conference papers on the topic "Lamproite"

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Neuhoff, Jackson, William O. Nachlas, Basil Tikoff, and Philip Neuhoff. "LAMPROITE-LIKE VOLCANICS ALONG THE WESTERN IDAHO SHEAR ZONE." In Joint 118th Annual Cordilleran/72nd Annual Rocky Mountain Section Meeting - 2022. Geological Society of America, 2022. http://dx.doi.org/10.1130/abs/2022cd-373956.

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Roark, Trevor, and Michael T. DeAngelis. "GEOCHEMICAL EXAMINATION OF GARNETS FROM THE PRARIE CREEK LAMPROITE, MURFREESBORO, ARKANSAS." In 51st Annual GSA South-Central Section Meeting - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017sc-289303.

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Spencer, Jason P., Thomas A. Colby, and Michael T. DeAngelis. "PETROLOGICAL AND GEOCHRONOLOGICAL INVESTIGATION OF THE BLUE BALL LAMPROITE NEAR WALDRON, ARKANSAS, USA." In Joint 53rd Annual South-Central/53rd North-Central/71st Rocky Mtn GSA Section Meeting - 2019. Geological Society of America, 2019. http://dx.doi.org/10.1130/abs/2019sc-326976.

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Kaur, Parminder, Gurmeet Kaur, Roger H. Mitchell, and Sebastian Tappe. "Nature and origin of lamproite hypabyssal intrusives from the Jharia basin in eastern India." In International Kimberlite Conference. University of Alberta, 2024. http://dx.doi.org/10.29173/ikc4041.

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Lupini, Isabella, Pamela Kempton, Andreas Möller, and Claudia Adam. "A geochronological perspective on the geodynamic models of kimberlite and lamproite magmatism in Kansas." In International Kimberlite Conference. University of Alberta, 2024. http://dx.doi.org/10.29173/ikc4190.

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Joni, Anele, G. H. Howarth, C. Harris, P. E. Janney, S. Hashibi, and J. Robey. "The Origin of Eclogitic Corundum and Garnet Xenocrysts from the Kareevlei Kaapvaal Lamproite (Group II Kimberlite)." In International Kimberlite Conference. University of Alberta, 2024. http://dx.doi.org/10.29173/ikc4163.

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Vieira Conceição, Rommulo, Vinicius Henrique Marcon, Márcio Roberto Wilbert de Souza, et al. "Carbonatite/Lamproite Liquid Imissibility in the Earth’s Mantle Through the Nefeline-Diopside-Kalsilite ±CO2, CH4, H2O Diagram." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.2680.

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Kempton, Pamela, Isabella Lupini, Andreas Möller, and Claudia Adam. "AGE CONSTRAINTS ON THE TIMING OF KIMBERLITE AND LAMPROITE MAGMATISM IN KANSAS BASED ON U-PB GEOCHRONOLOGY OF PEROVSKITE." In 59th Annual Meeting of the GSA South-Central Section - 2025. Geological Society of America, 2025. https://doi.org/10.1130/abs/2025sc-408280.

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Dobry, Catherine C., Sandra Jackson, Glenn Worthington, and Michael DeAngelis. "FIELD MAPPING AND GEOCHEMICAL ANALYSIS OF DIAMOND-BEARING LAMPROITE AND ADJACENT SEDIMENTS FROM THE WORTHINGTON DIAMOND MINE, PIKE COUNTY, ARKANSAS." In 59th Annual Meeting of the GSA South-Central Section - 2025. Geological Society of America, 2025. https://doi.org/10.1130/abs/2025sc-408143.

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Doucet, Luc S., and Andrea Giuliani. "Predicting geochemical and isotopic compositions as well as lithosphere-asthenosphere boundary depth and diamond grade in kimberlites and lamproite using Artificial Intelligence." In International Kimberlite Conference. University of Alberta, 2024. http://dx.doi.org/10.29173/ikc4080.

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Reports on the topic "Lamproite"

1

Kjarsgaard, B. A. Lamproite-hosted diamond. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1995. http://dx.doi.org/10.4095/208036.

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Hogarth, D. D., and T. D. Peterson. Lamproite dykes of southeast Baffin Island. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1996. http://dx.doi.org/10.4095/211704.

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Peterson, T. D., and R. H. Rainbird. Tectonic and Petrological Significance of Regional Lamproite - Minette Volcanism in the Thelon and Trans - Hudson Hinterlands, Northwest Territories. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1990. http://dx.doi.org/10.4095/131245.

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Peterson, T. D. Lamproites. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1996. http://dx.doi.org/10.4095/210971.

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Peterson, T. D. Lamproïtes. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1996. http://dx.doi.org/10.4095/210970.

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Kjarsgaard, B. A. Gîtes de diamants dans des lamproïtes. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1995. http://dx.doi.org/10.4095/208037.

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Hogarth, D. D., and T. D. Peterson. Dykes de lamproïte dans le sud-est de l'île de Baffin. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1996. http://dx.doi.org/10.4095/211705.

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