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1
Mian, I., and M. J. Le Bas. "The biotite-phlogopite series in fenites from the Loe Shilman carbonatite complex, NW Pakistan." Mineralogical Magazine 51, no. 361 (September 1987): 397–408. http://dx.doi.org/10.1180/minmag.1987.051.361.06.
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AbstractThe Loe Shilman carbonatite sheet complex comprises an extensive amphibole sovite which is intruded by minor biotite sovite and amphibole ankeritic carbonatite. The carbonatites have fenitized the country rocks to form a metasomatic zone c. 100 m wide of alternating mafic and felsic mica-bearing banded fenites which grade into slates and phyllites. Phlogopite-rich micas occur nearest to the carbonatite contact. The biotites occur in K-feldspar + albite ± Na-amphibole ± aegirine and ± phengite fenites produced by the intrusion of the early amphibole sovite. Aegirine buffered the iron distribution and the biotites became more magnesian. Veins cross-cutting the fenites consist of biotite and/or Ba-bearing K-feldspar, and are interpreted to result from solutions emanating from the biotite sovite. The ankeritic carbonatite is responsible for the formation ofphlogopite in the fenites in a c. 3 m wide zone adjacent to the carbonatite, and evidently are the result of fenitizing fluids rich in Mg. Chemical equations calculated to balance the reactions interpreted to have taken place in the fenites suggest that about 10% of the Al and Si in the protolith was mobilized and moved towards the carbonatites during fenitization, and that the fenitizing solutions were strongly alkaline and oxidizing.
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Jamieson, R. A., G. G. Hart, G. G. Chapman, and N. W. Tobey. "The contact aureole of the South Mountain Batholith in Halifax, Nova Scotia: geology, mineral assemblages, and isograds." Canadian Journal of Earth Sciences 49, no. 11 (November 2012): 1280–96. http://dx.doi.org/10.1139/e2012-058.
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The contact aureole at the eastern margin of the South Mountain Batholith (Halifax Pluton) underlies most of the city of Halifax, Nova Scotia. The Halifax Group in the study area includes two lithological units, the Cunard and Bluestone formations. Before intrusion, both had been affected by greenschist facies regional metamorphism and deformed into northeast–southwest-trending, regional upright folds associated with a strong slaty cleavage. Contact metamorphic isograds trend obliquely across the Halifax peninsula, at a high angle to regional structural trends. At 2.5–3 km from the intrusive contact, sparse cordierite spots mark the outer limit of the contact aureole. The biotite-in isograd is marked by the development of biotite within chlorite + muscovite stacks inherited from regional metamorphism. Pyrrhotite is the dominant sulphide mineral throughout the contact aureole. With increasing metamorphic grade, assemblages in both units are marked by increasing modal abundance of cordierite and biotite, with K-feldspar variably developed within ca. 600 m of the contact. However, there is a marked difference in the distribution and appearance of andalusite between the two units. In aluminous pelites of the Cunard formation, idioblastic chiastolite appears before biotite more than 1500 m from the contact. In the less aluminous Bluestone formation, andalusite is present only within ca. 500 m of the contact, where it forms xenoblastic, spongy crystals. In both units, the assemblage andalusite + biotite + K-feldspar ± cordierite is developed near the contact, with local fibrolite and evidence of incipient partial melting. Petrographic constraints suggest pressure–temperature conditions at the contact of ca. 2.5–3.0 kbar (1 kbar = 100 MPa) at ca. 650 °C.
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Shawwa, Nabil A., Robert P. Raeside, David W. A. McMullin, and Christopher R. M. McFarlane. "Employing contact metamorphism to assess the conditions of pluton emplacement and timing of recrystallization in southwestern Kellys Mountain, Cape Breton Island, Nova Scotia." Canadian Journal of Earth Sciences 54, no. 11 (November 2017): 1165–78. http://dx.doi.org/10.1139/cjes-2017-0052.
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At Kellys Mountain, Cape Breton Island, Nova Scotia, the late Neoproterozoic Glen Tosh formation (a low-grade metapsammite–metapelite unit of the George River Metamorphic Suite) has been intruded by diorite, granodiorite, and granite plutons, and the diorite hosts a narrow contact metamorphic aureole. New mapping and sampling in the contact aureole reveals that the metasedimentary rocks have reached amphibolite-facies metamorphism resulting in the development of neoformed biotite, muscovite, cordierite, ilmenite, garnet, andalusite, sillimanite, monazite, and spinel within the meta-pelite, a mineral assemblage also found in the Kellys Mountain Gneiss as a result of low-pressure regional metamorphism. Neoformed minerals and the disappearance of foliation defines a contact metamorphic aureole within 300 m of the pluton contacts. Petrographic and microprobe analyses of equilibrium assemblages in metapelitic units of the contact aureole yielded metamorphic pressures of 250 MPa, implying an intrusion depth of ∼9 km, with temperatures ranging from 365 to 590 °C. The presence of earlier-formed andalusite and garnet indicates the rocks may have initially undergone a low-pressure regional metamorphic event prior to contact metamorphism. Monazite in the contact aureole was dated using in-situ U–Pb methods and yielded an age of 480.9 ± 3.7 Ma, interpreted as the time of formation of the contact metamorphic aureole.
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Likhanov, Igor I., Vladimir V. Reverdatto, and Isabella Memmi. "Short-range mobilization of elements in the biotite zone of contact aureole of the Kharlovo gabbro intrusion (Russia)." European Journal of Mineralogy 6, no. 1 (February 4, 1994): 133–44. http://dx.doi.org/10.1127/ejm/6/1/0133.
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Benkó, Zsolt, Aberra Mogessie, Ferenc Molnár, Steven Hauck, Mark Severson, and Karl Ettinger. "The Influence of Thermal Differences and Variation of Cl–F–OH Ratios on Cu-Ni-PGE Mineralization in the Contact Aureole of the South Kawishiwi Intrusion, Duluth Complex." Geosciences 8, no. 12 (December 12, 2018): 474. http://dx.doi.org/10.3390/geosciences8120474.
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In the contact metamorphic aureole of the Duluth Complex, Cu-Ni-PGE mineralization occurs locally up to 100 m from the intrusion-footwall contact (Spruce Road area), whereas elsewhere (Dunka Pit deposit) the footwall granite and metapelite (Serpentine deposit) are barren. This study aimed to understand the effect of temperature and halogen fugacity variations on the presence or absence of mineralization in these footwall units. The mafic mineral assemblages, two-pyroxene, titanium-in-quartz, and biotite-apatite thermometers indicate that temperatures could be as high as 920 °C in the mineralized areas of the footwall, whereas the maximum temperature was lower by about 100 °C in the unmineralized part of the intrusion. Variation of the halogen concentrations and fugacities was monitored with the analysis of halogen concentrations in biotite and apatite. Fluorine and chlorine concentrations in biotite increase as a function of the distance from contact in the mineralized drill core and decrease in the unmineralized zones. Chlorine concentrations in apatite increase parallel with the distance from contact in the mineralized zones, whereas fluorine concentrations show only minor variation. Concentrations of these elements may have had subtle effect on the partial melting in the footwall units and indirectly facilitated the infiltration of the sulfide liquid into the footwall.
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Saunders, James A., and Gilles O. Allard. "The Scott Lake deposit: a contact-metamorphosed volcanogenic massive sulfide deposit, Chibougamau area, Quebec." Canadian Journal of Earth Sciences 27, no. 2 (February 1, 1990): 180–86. http://dx.doi.org/10.1139/e90-018.
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The Scott Lake volcanogenic massive sulfide deposit lies near the margin of a large, early kinematic granitoid intrusion in the vicinity of Chibougamau, Quebec. The deposit was contact metamorphosed by the intrusion, and subsequently it was metamorphosed to the greenschist facies during the Kenoran Orogeny. Pyrite, magnetite, and sphalerite are the most abundant metallic minerals, and minor amounts of chalcopyrite, pyrrhotite, and loellingite are also present. Both pyrite and magnetite locally occur as porphyroblasts up to several centimetres in diameter. Metamorphic textures developed in the massive sulfide ore appear to have formed during contact metamorphism, and they remained intact through the subsequent regional event. However, silicate minerals (biotite and possibly amphibole) that grew during contact metamorphism were largely retrograded during regional metamorphism. The presence of biotite indicates that contact metamorphism took place at 400°–500 °C. Application of the sphalerite geobarometer gives a pressure of approximately 4.5 kbar (450 MPa), which probably reflects the later regional event.
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Pawar, Rasika, Vasudeo Zambare, Siddhivinayak Barve, and Govind Paratkar. "Application of Protease Isolated from Bacillus sp. 158 in Enzymatic Cleansing of Contact Lenses." Biotechnology(Faisalabad) 8, no. 2 (March 15, 2009): 276–80. http://dx.doi.org/10.3923/biotech.2009.276.280.
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Heinzelmann, Elsbeth. "Olten Meeting – A Contact Forum for Biotech - November 19, 2008." CHIMIA International Journal for Chemistry 63, no. 1 (February 25, 2009): 74–75. http://dx.doi.org/10.2533/chimia.2009.74.
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Dubosq, Renelle, David Schneider, Alfredo Camacho, and Christopher Lawley. "Geochemical and Geochronological Discrimination of Biotite Types at the Detour Lake Gold Deposit, Canada." Minerals 9, no. 10 (September 30, 2019): 596. http://dx.doi.org/10.3390/min9100596.
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The Detour Lake deposit is at a faulted contact between mafic volcanic and siliciclastic to volcaniclastic rocks, differing from other orogenic Au deposits in the dominantly greenschist facies Abitibi region, by possessing amphibolite facies assemblages. Consequently, typical indicator minerals for mineralization, like secondary biotite, may not be useful for locating ore zone, due to the challenge of distinguishing hydrothermal versus metamorphic and magmatic phases. Herein, geochemical and 40Ar/39Ar geochronological data are presented for biotite from mineralized and barren (distal) magmatic rocks to characterize potential geochemical and geochronological variations between biotite types. Petrological observations reveal four biotite types: (1) Biotite hosted in mineralized, sulphidized quartz-calcite veins, (2) halo biotite at the margins of the aforementioned veins; (3) host rock biotite defining the foliation within the mafic volcanic rocks of the deposit; and (4) biotite defining the foliation within the barren meta-plutonic host rocks. Chemical analysis reveals a lower Ti- and higher Mg-content of mineralized biotite types, indicative of secondary hydrothermal processes. 40Ar/39Ar ages for all biotite types (2600–2390 Ma) post-date the main syn-deformation mineralization event at Detour Lake (≤2700 Ma). These results suggest chemical variations within biotite are due to a post-mineralization hydrothermal event, thus biotite should be used cautiously as a vector for gold mineralization in amphibolite facies terranes.
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Schumacher, Renate. "Zincian staurolite in Glen Doll, Scotland." Mineralogical Magazine 49, no. 353 (September 1985): 561–71. http://dx.doi.org/10.1180/minmag.1985.049.353.10.
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AbstractTextures and relict mineralogy in the Dalradian gneisses from the southern contact aureole of the Glen Doll diorite trace the development of three stages of metamorphism through regional and contact metamorphic phases. Regional metamorphic stage I is characterized by the stability of sillimanite+muscovite; recognition of a subsequent regional metamorphic stage II of lower grade is based on textural criteria, the stability of kyanite and staurolite + quartz, and geothermometry/geobarometry. The breakdown of zincian staurolite occurred under the conditions of contact metamorphism (stage III). Textural evidence from the outer part of the contact aureole suggests that zincian staurolite broke down by the following oxidation reaction:zincian staurolite + muscovite + quartz + O2 → andalusite + Zn-rich spinel + magnetite + biotite + H2O.Various stages of completion of this reaction have been observed in different parts of a sample. Predominance of magnetite over Zn-rich spinel (⩽ 14 wt. % ZnO) as a breakdown product can be explained by the initial breakdown of Fe-staurolite component + muscovite + quartz+O2 to form andalusite+biotite+magnetite. These product phases were joined by the Zn-rich spinel when sufficient Zn-staurolite component had concentrated in the unreacted staurolite. Rare local examples where Zn-rich spinel is dominant over magnetite may reflect lower O2 fugacity and/or higher initial Zn contents of the staurolite.
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Barr, Sandra M., Alan S. Macdonald, and John Blenkinsop. "The Cheticamp pluton: a Cambrian granodioritic intrusion in the western Cape Breton Highlands, Nova Scotia." Canadian Journal of Earth Sciences 23, no. 11 (November 1, 1986): 1686–99. http://dx.doi.org/10.1139/e86-156.
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The Cheticamp pluton consists of biotite granodiorite (locally megacrystic) in the north and museovite–biotite granodiorite in the south, in probable faulted contact. These two rock types, especially the biotite granodiorite, show a broad range in modal and chemical compositions. They are interpreted to be cogenetic, with the museovite–biotite grandiorite derived from the biotite granodiorite by crystal fractionation involving mafic minerals, plagioclase, and sphene. The overall peraluminous composition of the suite resulted from the fractionation process, probably enhanced by alteration, rather than from derivation from peraluminous source rocks.A seven-point, whole-rock, Rb–Sr isochron indicates an age of 525 ± 40 Ma. The pluton intruded dioritic rocks and quartzo-feldspathic gneisses, thus indicating Precambrian ages for these units. It probably also postdates the Western Highlands volcanic–sedimentary complex, a major undated stratigraphic unit in the Cape Breton Highlands. Although the age overlaps the range of Rb–Sr ages from plutons of the Avalon Terrane of the Appalachian orogen, the geological setting of the Cheticamp pluton differs from that of true Avalonian plutons, such as those in southeastern Cape Breton Island.
12
Tettelaar, Tanya, and Aphrodite Indares. "Granulite-facies regional and contact metamorphism of the Tasiuyak paragneiss, northern Labrador: textural evolution and interpretation." Canadian Journal of Earth Sciences 44, no. 10 (October 1, 2007): 1413–37. http://dx.doi.org/10.1139/e07-029.
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The Tasiuyak paragneiss at the western margin of the Nain Plutonic Suite has been subjected to two granulite-facies metamorphic events: (i) regional metamorphism during the Paleoproterozoic Torngat orogeny, and (ii) contact metamorphism due to emplacement of the Mesoproterozoic Nain Plutonic Suite. Regional metamorphism led to partial melting of pelitic rocks and the development of a locally well-preserved sequence of prograde and retrograde textures. These textures are partly controlled by bulk composition and formed in the pressure–temperature (P–T) field of the continuous reaction: biotite + sillimanite + plagioclase + quartz = garnet + K-feldspar + melt, along a hairpin P–T path with peak conditions of ~8–10 kbar (0.8–1.0 GPa) and up to 870 °C in the NaKFMASH (Na2O–K2O–FeO–MgO–Al2O3–SiO2–H2O) system. These textures controlled the development of the contact metamorphic assemblages. Contact metamorphism of the pelitic rocks between the Tessiarsuyungoakh intrusion and the Makhavinekh Lake pluton led to growth of orthopyroxene-cordierite symplectite after garnet–biotite, and cordierite–spinel symplectite after garnet–sillimanite. These phase associations attest to reactions in specific microtextural settings, some of which produced a second generation of partial melt. Maximum temperatures were above ~750 °C and pressures were lower than those of the regional metamorphism. The aureole around the Makhavinekh Lake pluton is ~4 km wide and shows a progressive development of the contact metamorphic assemblages toward the pluton. In contrast, the contact metamorphic overprint is incipient around the Tessiarsuyungoakh intrusion, which developed a ~20 m wide contact aureole and is most prominent in screens of paragneiss within that intrusion.
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Bose, Sankar, Kaushik Das, and Masato Fukuoka. "Fluorine content of biotite in granulite-grade metapelitic assemblages and its implications for the Eastern Ghats granulites." European Journal of Mineralogy 17, no. 5 (October 18, 2005): 665–74. http://dx.doi.org/10.1127/0935-1221/2005/0017-0665.
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Heflik, Wiesław, Lucyna Natkaniec-Nowak, Paweł P. Zagożdżon, Katarzyna D. Zagożdżon, Magdalena Dumańska-Słowik, and Janina Jarocka. "Mineralogical and Petrographical Characteristics of Hornfels from Kowary (The Lower Silesia)." Gospodarka Surowcami Mineralnymi 32, no. 2 (June 1, 2016): 45–62. http://dx.doi.org/10.1515/gospo-2016-0013.
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Abstract Hornfels from the closed “Wolność” mine (Kowary, the Lower Silesia) are recognized as thermally metamorphosed rocks belonging to hornblende-hornfels facies or locally a facies of pyroxene hornfels. Their texture reveal the traces of some deformations such as folding or fractures. Their protholit is described as a pelitic deposit enriched with clay minerals. The sediment was altered into meta-pelities-aleurites after the diagenesis, and later the rock was intensely thermally metamorphosed at the contact with the intrusion of the Karkonosze granitoid. Three varieties are distinguished based on their colour: green, grey and black. Green and black colours result from the predominance of hornblende and biotite over other rock components, respectively. Whereas grey hornfels are composed of similar amounts of both mafic minerals: biotite and hornblende. Quartz, mica minerals (biotite and muscovite), amphibole, (hornblende), acid plagioclase and andalusite, epidote group (clinozoisite), orthoclase and pyroxene make up hornfels components. Locally, andalusite is accompanied by sillimianite, which indicates a higher degree of contact metamorphism alterations. Three generations of minerals are distinguished in the rocks: allogenic (I), metamorphic (II) and hydrothermal (III). The allogenic phases are represented by heavy minerals such as zircon, apatite and monazite, which are characteristic of the protholit. The main components of the rocks (e.g. quartz, hornblende, feldspars, andalusite, sillimanite, mica minerals) belong to metamorphic minerals. Chalcopyrite, pyrite and fluorite are surely hydrothermally originated phases. Granitoides found at the contact zone with hornfels indicate traces of metasomatic alteration as a result of endomorphism in this region.
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Sun, Yue, Yuanli Wang, Lei Li, Lijing Sun, Linyan He, and Xiafang Sheng. "Distinct biotite-weathering activities of Arthrobacter pascens F74 under different contact conditions." Journal of Basic Microbiology 60, no. 4 (December 16, 2019): 362–71. http://dx.doi.org/10.1002/jobm.201900518.
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Noh, Jungrae, Changyeob Kim, Vinod O. Samuel, Yirang Jang, Seung-Ik Park, and Sanghoon Kwon. "Fluid Infiltration and Mass Transfer along a Lamprophyre Dyke–Marble Contact: An Example from the South-Western Korean Peninsula." Minerals 10, no. 9 (September 20, 2020): 828. http://dx.doi.org/10.3390/min10090828.
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In this contribution, we report the metasomatic characteristics of a lamprophyre dyke–marble contact zone from the Hongseong–Imjingang belt along the western Gyeonggi Massif, South Korea. The lamprophyre dyke intruded into the dolomitic marble, forming a serpentinized contact zone. The zone consists of olivine, serpentine, calcite, dolomite, biotite, spinel, and hematite. Minor F and Cl contents in the serpentine and biotite indicate the composition of the infiltrating H2O-CO2 fluid. SiO2 (12.42 wt %), FeO (1.83 wt %), K2O (0.03 wt %), Sr (89 ppm), U (0.7 ppm), Th (1.44 ppm), and rare earth elements (REEs) are highly mobile, while Zr, Cr, and Ba are moderately mobile in the fluid. Phase equilibria modelling suggests that the olivine, spinel, biotite, and calcite assemblage might be formed by the dissolution of dolomite at ~700 °C, 130 MPa. Such modelling requires stable diopside in the observed conditions in the presence of silica-saturated fluid. The lack of diopside in the metasomatized region is due to the high K activity of the fluid. Our log activity K2O (aK2O)–temperature pseudosection shows that at aK2O~−40, the olivine, spinel, biotite, and calcite assemblage is stable without diopside. Subsequently, at ~450 °C, 130 MPa, serpentine is formed due to the infiltration of H2O during the cooling of the lamprophyre dyke. This suggests that hot H2O-CO2 fluids with dissolved major and trace elements infiltrated through fractures, grain boundaries, and micron-scale porosity, which dissolved dolomite in the marble and precipitated the observed olivine-bearing peak metasomatic assemblage. During cooling, exsolved CO2 could increase the water activity to stabilize the serpentine. Our example implies that dissolution-reprecipitation is an important process, locally and regionally, that could impart important textural and geochemical variations in metasomatized rocks.
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Douglas, Thomas A., Paul W. Layer, Rainer J. Newberry, and Mary J. Keskinen. "Geochronologic and thermobarometric constraints on the metamorphic history of the Fairbanks Mining District, western Yukon-Tanana terrane, Alaska." Canadian Journal of Earth Sciences 39, no. 7 (July 1, 2002): 1107–26. http://dx.doi.org/10.1139/e02-024.
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This study presents new petrologic and thermochronologic information from the Fairbanks district of east central Alaska that indicate a complex metamorphic and structural history for the western YukonTanana terrane. Garnetbiotite and garnetpyroxene thermometry and jadeite barometry yield prograde temperatures and pressures for the Chatanika eclogite (523°C, 1415 kbar (1 kbar = 100 MPa)). Cooling from peak eclogitization is estimated from 40Ar/39Ar single grain geochronology at ~210180 Ma. Secondary white mica ages of 140115 Ma along the fault contact between eclogite and underlying lower amphibolite-facies rocks constrain the age of the event that placed the Chatanika eclogite over the Fairbanks schist. Based on observations from field mapping and diamond drill samples, we interpret this structural contact as a thrust fault. Garnetbiotite mineral pairs are reset by as much as 200°C within this fault zone. Biotite and white mica ages of ~100110 Ma, combined with Jurassic amphibole ages in Fairbanks schist samples, indicate the Fairbanks schist and Chatanika eclogite cooled through biotite and white mica argon closure temperatures in the early Cretaceous. Intrusion of mid-Cretaceous, calc-alkalic, gold-related granitic plutons in the Fairbanks district are evidenced by loss of radiogenic argon in many of the 40Ar/39Ar age fractions. Eocene basalt is visible in six widely separated localities within the eastern part of the Fairbanks district. However, the pervasiveness of a 50 Ma resetting event in samples as far as 30 km from present day basalt localities indicates the Eocene flows were either deposited throughout the Fairbanks area or are associated with large plutons at depth.
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Mitchell, Isabelle, Stefan Steiner, Michael Altorfer, and Laura Suter-Dick. "Swiss Startup Framework: A Highly Effective Network Supporting the Generation of Emerging Biotech Businesses." CHIMIA International Journal for Chemistry 74, no. 10 (October 28, 2020): 765–67. http://dx.doi.org/10.2533/chimia.2020.765.
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For over 50 years, Switzerland has been one of the leading countries driving innovation in biotechnology and its industrial applications. Today, some 1,000 biotech companies form a tightly knit, cross-functional network ranging from research through to manufacturing. This network comprises R&D companies, contract research organizations, and highly specialized advisors and biotech investors. Together, they form an external innovation pool that complements the in-house R&D capacity of the large multi-national pharma companies. A highly effective startup framework, solid acceleration mechanisms, and innovative investors enable the emergence of a continuous flow of biotech startups that revitalize the industry with new technologies and products supporting drug development and diagnostics.
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Puziewicz, Jacek, and Anna Pietranik. "Two-mica andalusite-bearing granite with no primary muscovite: constraints on the origin of post-magmatic muscovite in two-mica granites." Geoscience Records 3, no. 1 (December 1, 2016): 7–17. http://dx.doi.org/10.1515/georec-2016-0006.
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Abstract The two-mica granite from Gęsiniec (Strzelin Granitic Massif, SW Poland) consists of quartz, K-feldspar, normally zoned plagioclase (30 ± 7 % An), subordinate biotite and muscovite and magmatic andalusite. Andalusite crystallised before the outer parts of plagioclase grains were formed. Biotite has constant Fe/(Fe + Mg) ratio of approximately 0.81. Five textural types of muscovite occur in the granite: (1) muscovite replacing andalusite, (2) embayed interstitial muscovite, (3) muscovite forming aggregates with biotite, (4) muscovite accompanying biotite and chlorite in microfissures and (5) fine muscovite forming fringes at the contact between larger muscovite plates and K-feldspar. They are commonly associated with albite. Crystallisation of muscovite started significantly below the granite solidus, mostly by the replacement of andalusite. Formation of muscovite continued during cooling of host rock. The growth of individual plates was initiated at different undercoolings and the plates whose crystallisation was frozen at different stages of growth occur. Those that were formed earlier are richer in titanium and iron relative to the later ones. As the rock contains no Ti and Fe saturating phases, the content of Ti and Mg in muscovite depends on their local availability. The homogeneous Fe/(Fe + Mg) ratio of biotite indicates that it was re-equilibrated at the post-magmatic stage.
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Lihter, Iva, Kyle P. Larson, Sudip Shrestha, John M. Cottle, and Alex D. Brubacher. "Contact metamorphism of the Tethyan Sedimentary Sequence, Upper Mustang region, west-central Nepal." Geological Magazine 157, no. 11 (April 24, 2020): 1917–32. http://dx.doi.org/10.1017/s0016756820000229.
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AbstractThe Upper Mustang region of west-central Nepal contains exposures of metamorphosed Tethyan Sedimentary Sequence rocks that have been interpreted to reflect either contact metamorphism related to the nearby Mugu pluton or regional metamorphism associated with the North Himalayan domes. New monazite geochronology results show that the Mugu leucogranite crystallized at c. 21.3 Ma, while the dominant monazite age peaks from the surrounding garnet ± staurolite ± sillimanite schists range between c. 21.7 and 19.4 Ma, generally decreasing in age away from the pluton. Metamorphic temperature estimates based on Ti-in-biotite and garnet–biotite thermometry are highest in the specimens closest to the pluton (648 ± 24°C and 615 ± 25°C, respectively) and lowest in those furthest away (578 ± 24°C and 563 ± 25°C, respectively), while pressure estimates are all within uncertainty of one another, averaging 5.0 ± 0.5 kbar. These results are interpreted to be consistent with contact metamorphism of the rocks in proximity to the Mugu pluton, which was emplaced at c. 18 ± 2 km depth after local movement across the South Tibetan detachment system had ceased. While this new dataset helps to characterize the metamorphic rocks of the Tethyan Sedimentary Sequence and provides new constraints on the thickness of the upper crust, it also emphasizes the importance of careful integration of metamorphic conditions and inferred processes that may affect interpretation of currently proposed Himalayan models.
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Owen, J. Victor. "Cordierite + spinel parageneses in pelitic gneiss from the contact aureoles of the Mistastin batholith (Quebec) and the Taylor Brook gabbro complex (Newfoundland)." Canadian Journal of Earth Sciences 28, no. 3 (March 1, 1991): 372–81. http://dx.doi.org/10.1139/e91-034.
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The contact aureoles of the Mistastin batholith and the Taylor Brook gabbro complex contain cordierite + spinel-bearing assemblages derived from quartz-, K-feldspar-, sillimanite-, garnet-, and biotite-bearing pelitic gneiss. Andalusite occurs locally. As a result of continuous, cordierite-forming reactions, garnet and biotite have recrystallized to relatively Fe-rich compositions compared with their counterparts outside the aureoles.Mosaics of fine-grained cordierite and spinel replace sillimanite and biotite throughout the Mistastin aureole. Similar assemblages and textures are preserved in metapelite in the outer part of the Taylor Brook aureole, where garnet adjacent to sillimanite is replaced by cordierite + spinel. The formation of spinel-free cordierite porphyroblasts by garnet-, sillimanite-, biotite-, and quartz-consuming reactions depleted metapelites in both aureoles in quartz, permitting the formation of the undersaturated assemblages. The undersaturated cordierite + spinel assemblages formed on a domainal scale (individually, a few hundred cubic millimetres in volume) and coexist metastably with saturated assemblages elsewhere in the same rock. Peak temperatures (700–750 °C) determined for both aureoles were insufficient to stabilize quartz + spinel parageneses owing to the low gahnite content of the oxide (ZnO < 2 wt.%).Metapelites in the innermost part of the Taylor Brook aureole appear to have been desilicified by the formation and fractionation of anatectic melt, yielding migmatitic rocks virtually devoid of quartz and K-feldspar. In contrast, migmatite in the inner part of the Mistastin aureole retains a quartz + two-feldspar mineralogy, so, as in the nonmigmatitic paragneiss, undersaturated assemblages are present only on a domainal scale.These aureole rocks demonstrate that undersaturated assemblages are not only characteristic of thermally- recrystallized low-grade pelites but also can occur in contact aureoles developed in granulite-facies paragneiss. Aluminous rocks can become undersaturated by subsolidus, quartz-consuming reactions yielding cordierite, or by the formation of anatectic liquids.
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ELEFTHERIADIS, G., W. FRANK, and K. PETRAKAKIS. "40 Ar/39/Ar dating and cooling history of the Pangeon granitoids, Rhodope Massif (Eastern Macedonia, Greece)." Bulletin of the Geological Society of Greece 34, no. 3 (January 1, 2001): 911. http://dx.doi.org/10.12681/bgsg.17116.
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The Pangeon granitoids are distinguished into two pétrographie types with sharp contacts: (a) heterogranular, medium- to coarse-grained, hornblende+biotite- bearing porphyritic tonalités and granodiorites (PTG), and, (b) equigranular, medium-grained, biotite±muscovite-bearing granodiorites and granites (MGG). Dark-coloured, medium-grained monzodioritic enclaves occur in PTG rocks. Hornblende 40Ar/39Ar spectra from the PTG rocks yielded cooling ages of 21.7±0.5 Ma to 18.8±0.6 Ma. With the exception one sample, the corresponding hornblende ages from enclaves coincide well with the above ages. The age of 21.7±0.5 Ma is considered as the lower limit for the PTG rocks emplacement. Muscoviteplateau ages of c. 15.7±0.5 Ma and total gas biotite ages of 15.2±0.4 Ma to 13.8±0.5 Ma from the studied rocks, constrain the cooling history of the Pangeon granitoids (with some local variations) in the range 430 - 300Ί C.
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Neves, Luis J. P. F. "Trace element content and partitioning between biotite and muscovite of granitic rocks: a study in the Viseu region (Central Portugal)." European Journal of Mineralogy 9, no. 4 (July 23, 1997): 849–58. http://dx.doi.org/10.1127/ejm/9/4/0849.
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Bröcker, M., and L. Franz. "The contact aureole on Tinos (Cyclades, Greece): tourmaline-biotite geothermometry and Rb-Sr geochronology." Mineralogy and Petrology 70, no. 3-4 (December 14, 2000): 257–83. http://dx.doi.org/10.1007/s007100070006.
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Shanmuga Priyaa, S., and S. Sanjeevi. "Delineation of sub-pixel level sedimentary litho-contacts by super resolution mapping of Landsat image." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-8 (December 23, 2014): 1389–96. http://dx.doi.org/10.5194/isprsarchives-xl-8-1389-2014.
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To delineate the geological formation at the surface, satellite image classification approaches are often preferred. This study aims to produce a super resolved map with better delineation of the litho-contacts from the medium resolution Landsat image. Conventionally used per-pixel classification provides an output map at the same resolution of the satellite image, while the super resolved map provides the high resolution output map using the medium resolution image. In this study, four test sites are considered for delineating different litho-contacts using super resolution mapping approach in Cuddalore district, southern India. The test sites consists of charnockite, fissile hornblende-biotite gneiss, marine sandstone and sandstone with clay, limestone with calcareous shale and clay, clay with limestone bands/lenses, mio-pliocene and quaternary argillaceous and calcareous sandstone, fluvial and fluviomarine formations. This work compares the per-pixel, super resolved output derived from linear spectral unmixing (LSU) based HNN and spectral angle mapper (SAM) based HNN approaches. The super resolution mapping approach was performed on the medium resolution (30 m) Landsat image to obtain the litho-contact maps and the results are compared with the existing maps and observations from field visits. The results showed improved accuracy (90.92%) of the map prepared by the SAM based super resolution approach compared to the LSU based super resolution approach (90.14%) and the maximum likelihood classification approach (83.74%). Such an improved accuracy of the super resolved map (6 m resolution) is due to the fact that the lithological mapping is done not merely at the resolution of the image, but at the sub-pixel level. Hence, it is inferred that super resolution mapping applied to multispectral images may be preferred for mapping lithounits and litho-contacts than the conventional per-pixel and sub-pixel image classification methods.
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Majka, Jarosław, Mateusz P. Sęk, Stanisław Mazur, Bożena Gołębiowska, and Adam Pieczka. "Polymetamorphic evolution of pelites inferred from tourmaline zoning – the Rędziny hornfels case study at the eastern contact of the Karkonosze Granite, Sudetes, Poland." Mineralogia 49, no. 1-4 (December 1, 2018): 17–34. http://dx.doi.org/10.2478/mipo-2018-0003.
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AbstractTourmaline occurring in hornfelses from the eastern envelope of the Karkonosze Granite (Western Sudetes, Poland) reveals at least two stages of crystallization expressed by its complex zoning. The cores and mantles of the crystals probably grew during prograde metamorphism under intermediate pressure-temperature conditions reflected by increasing Mg, Ti and Ca. Outermost rims show enrichment in Al and Ca, indicating growth during contact metamorphism in the presence of an Al-saturating phase. The Ti-content in biotite indicates that the temperature of the contact metamorphic event did not exceed 650ºC. The presence of andalusite and the lack of garnet and cordierite also indicates pressure conditions of ~ 2-3 kbar, typical of the C1 bathozone of Carmichael (1978) or the P1 bathozone of Pattison (2001).
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Ullah, Rahman, Nie Fengjuin, Zhang Chengyong, Saqib Izhar, Idrees Safdar, Zhang Xin, and Asim Ali. "Occurrence of a Likely Tuff Bed between the Middle and Upper Siwaliks, Taunsa area, Dera Ghazi Khan, Eastern Sulaiman Range, Pakistan." International Journal of Economic and Environmental Geology 11, no. 1 (July 6, 2020): 24–34. http://dx.doi.org/10.46660/ijeeg.vol11.iss1.2020.407.
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A likely tuff bed lies along the gradational contact of the Middle and Upper Siwaliks in eastern Sulaiman Range, Taunsa area of Dera Ghazi Khan district, Pakistan. This tuffaceous unit is 0.5–3 m thick and extends for 10 km along the north-south strike in the eastern limb of the Zindapir anticline. It is greyish white to white on fresh surface, fine-grained to silty at the bottom and clayey at the top and thus shows a fining upward grain-size grading. The lower part of the ash bed shows a prominent lamination defined by megascopically visible abundant biotite, while the central and upper parts are so fine-grained that the individual minerals cannot be seen in hand sample. Unlike the lower well-laminated part, the central and upper parts are crudely laminated to apparently massive. The bulk samples analysed with X-ray diffraction consist of quartz, feldspar (plagioclase), biotite, clays, calcite and some ore mineral likely spinel, while the clay-size fractions contain illite, chlorite, biotite and probably their mixed-layered varieties. The colour, texture, presence of abundant biotite and stratigraphic position of the Taunsa tuff correlate with those reported from Potwar plateau and from Kashmir basin. However, the apparent absence of smectite from the XRD pattern makes the Taunsa ash bed different from both Potwar and Kashmir tuffs. The present stratigraphic position of the tuff bed corresponds to shallow diagenetic zone, while the absence of smectite in the tuff and crystallinity of illite suggest that the tuff is probably derived upon reworking from a deeper diagenetic zone belonging to a lower stratigraphic level. The Eocene or other older pre-Siwalik units in Pakistan may have or had some primary ashfall deposits as reported in the northwestern Himalayas of India. This older volcanic ash may have been reworked to its present site of occurrence along the gradational contact of the Middle and the Upper Siwaliks in Taunsa area of Dera Ghazi Khan. However, the primary source of the Taunsa tuff may belong more likely to Chagai arc in Pakistan than to Dacht-e-Nawar volcanic complex in Afghanistan.
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Ullah, Rahman, Nie Fengjuin, Zhang Chengyong, Saqib Izhar, Idrees Safdar, Zhang Xin, and Asim Ali. "Occurrence of a Likely Tuff Bed between the Middle and Upper Siwaliks, Taunsa area, Dera Ghazi Khan, Eastern Sulaiman Range, Pakistan." International Journal of Economic and Environmental Geology 11, no. 1 (July 6, 2020): 24–34. http://dx.doi.org/10.46660/ojs.v11i1.407.
Full textAbstract:
A likely tuff bed lies along the gradational contact of the Middle and Upper Siwaliks in eastern Sulaiman Range, Taunsa area of Dera Ghazi Khan district, Pakistan. This tuffaceous unit is 0.5–3 m thick and extends for 10 km along the north-south strike in the eastern limb of the Zindapir anticline. It is greyish white to white on fresh surface, fine-grained to silty at the bottom and clayey at the top and thus shows a fining upward grain-size grading. The lower part of the ash bed shows a prominent lamination defined by megascopically visible abundant biotite, while the central and upper parts are so fine-grained that the individual minerals cannot be seen in hand sample. Unlike the lower well-laminated part, the central and upper parts are crudely laminated to apparently massive. The bulk samples analysed with X-ray diffraction consist of quartz, feldspar (plagioclase), biotite, clays, calcite and some ore mineral likely spinel, while the clay-size fractions contain illite, chlorite, biotite and probably their mixed-layered varieties. The colour, texture, presence of abundant biotite and stratigraphic position of the Taunsa tuff correlate with those reported from Potwar plateau and from Kashmir basin. However, the apparent absence of smectite from the XRD pattern makes the Taunsa ash bed different from both Potwar and Kashmir tuffs. The present stratigraphic position of the tuff bed corresponds to shallow diagenetic zone, while the absence of smectite in the tuff and crystallinity of illite suggest that the tuff is probably derived upon reworking from a deeper diagenetic zone belonging to a lower stratigraphic level. The Eocene or other older pre-Siwalik units in Pakistan may have or had some primary ashfall deposits as reported in the northwestern Himalayas of India. This older volcanic ash may have been reworked to its present site of occurrence along the gradational contact of the Middle and the Upper Siwaliks in Taunsa area of Dera Ghazi Khan. However, the primary source of the Taunsa tuff may belong more likely to Chagai arc in Pakistan than to Dacht-e-Nawar volcanic complex in Afghanistan.
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Owen, J. Victor. "Significance of epidote in orbicular diorite from the Grenville Front zone, eastern Labrador." Mineralogical Magazine 55, no. 379 (June 1991): 173–81. http://dx.doi.org/10.1180/minmag.1991.055.379.05.
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AbstractOrbicules in diorite from the Grenville Front zone of eastern Labrador are defined by shell structures alternately enriched and depleted in biotite, epidote and magnetite. Hornblende occurs locally in orbicule cores and the matrix, but not in the shells. The shells enclose plagioclase-rich (An40–45), leucodioritic cores containing biotite, epidote, magnetite and/or hornblende-bearing mafic clots. The matrix of the orbicules is mineralogically-similar to the orbicule cores, but is mesocratic, and contains relatively sodic plagioclase and accessory quartz and K-feldspar. In places, hornblende contains quartz oikocrysts, implying the resorption of early-formed clinopyroxene, and is rimmed by biotite and epidote. The latter phases also occur as inclusions in quartz-free hornblende interpreted to have crystallized directly from the magma. Epidote has a pistacite content of 21 to 26 and occurs as (1) tiny, idiomorphic crystals (‘epidote I’) enclosed by plagioclase or hornblende, and (2) relatively large (to 1 mm) grains with vermicular textures (‘epidote II’), particularly where in mutual contact with biotite (or hornblende) and plagioclase. These microstructures suggest that epidote is a magmatic phase which formed by direct crystallization from the magma, and by reaction of previously-formed minerals with the magma.The following approximate paragenetic sequence has been inferred for orbicule cores and the matrix: clinopyroxene (clinopyroxene resorbed [→ poikilitic hornblende]), epidote I, Ca-Na plagioclase, biotite, hornblende (biotite and/or hornblende ± plagioclase resorbed [→ epidote II]), quartz + K-feldspar. Biotite compositions became progressively more Fe-rich during crystallization (XMg ⋍ 0.6 → 0.4), and the first-formed plagioclase (inclusions in quartz-free hornblende in orbicule cores) is more calcic (An51) than the last (matrix grains: An35).The appearance of epidote early in the crystallization history of the diorite testifies to elevated PH2O and PTotal (PT). The most aluminous hornblende indicates maximum PT of 5 to 6 kbar. Orbicule shell structures are interpreted to have crystallized from supercooled boundary layers enclosing water-saturated globules within the dioritic magma. Although sufficient to suppress the formation of hornblende in the shell structures, the extent of magma supercooling did not permit the development of comb layering in the orbicules. Supercooling is attributed to an influx into the magma of water from an unidentified source.
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Recio, C., A. E. Fallick, and J. M. Ugidos. "A stable isotopic (δ18O, δD) study of the late-Hercynian granites and their host-rocks in the Central Iberian Massif (Spain)." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 83, no. 1-2 (1992): 247–57. http://dx.doi.org/10.1017/s0263593300007938.
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ABSTRACTStable isotopic ratios (mainly 18O/16O, but also D/H) have been measured for the three most important types of late-Hercynian granites, and their hosts, in the western area of the Central Iberian Massif (CIM), Spain. These granites are amphibole-bearing biotite granites, biotite granites and cordierite-bearing biotite granites. No intrusive relationships have been observed among them; the contact of each granite with the others is always gradational. Host-rocks are Precambrian/Cambrian metasediments, ranging from low-grade schists to migmatites (nebulites).Whole-rock δ18OSMOW values are as follows: amphibole-bearing biotite granites 8·9 ± 0·58% (1σ, n = 17); biotite granites 9·0 ± 0·35% (1σ, n = 11); cordierite-bearing biotite granites 9·6 ± 0·24% (1σ, n = 21). δ18O values for nebulites, into which some of these granites were emplaced, are significantly higher, at 11·1 ± 0·58‰ (1σ, n = 13). The Precambrian to Cambrian shales gave an average value of δ18O = 11·9 ± l·23‰ (lδ, n = 5). Whole-rock oxygen isotope ratios indicate that the origin of the granites was in neither purely sedimentary/metasedimentary rocks nor pristine mantle melts. δ18O values close to 9·0‰ require a crustal protolith, having an important recycled component.Oxygen isotope results are compatible with the cordierite-bearing granites being generated by assimilation of nebulite-like material by a biotite granite magma. However, 18O/16O of mineral separates obtained from the three different granites and the nebulite indicate that isotopic equilibrium, if ever reached, has not been preserved. The modified isotopic equilibrium is attributed to fluid activity, but mineral-pair δ-δ plots suggest that the granite system behaved as a closed system, and that the fluid was deuteric (magmatic) in origin. This implies that if assimilation did happen, it occurred at a temperature higher than the closure temperature of the different minerals to isotopic exchange. In a δ18O vs δD plot, hornblende and biotite separates from the granites plot within the igneous field. A simple mesocrustal anatectic origin for the peraluminous late Hercynian granites of the western area of the CIM is difficult to sustain on the basis of the stable isotope data, consistent with other field, petrographic and geochemical evidence. Cordierite in the cordierite-bearing granites is not “restitic” from a deep source area, but rather is xenocrystic from the high-grade metamorphic country rock (nebulites).
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Preston, R. J., M. J. Hole, and J. Still. "The occurrence of Zr-bearing amphiboles and their relationships with the pyroxenes and biotites in the teschenite and nepheline syenites of a differentiated dolerite boss, Islay, NW Scotland." Mineralogical Magazine 64, no. 3 (June 2000): 459–68. http://dx.doi.org/10.1180/002646100549526.
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AbstractThe Cnoc Rhaonastil minor dolerite intrusion on Islay, NW Scotland represents a single body of alkali olivine basalt magma which differentiated in situ, from leucodolerite, through teschenite to minor nepheline syenite. The syenites occur as isolated nests and pegmatitic schlieren within the leucodolerite, and schlieren of gabbroic pegmatite also occur at the margin of the teschenite. The differentiated rocks contain pyroxene, amphibole and biotite of variable compositions which reflect both primary fractionation processes and late-stage deuteric alteration and reaction.Mafic phases within the gabbroic pegmatite, teschenite and syenite are typically rimmed and speckled with biotite, the composition of which is controlled by the local environment of crystallization. The nepheline syenites contain primary ferro-kaersutite which, where in contact with interstitial patches, has been altered to arfvedsonite, which occasionally contains up to 1.2 wt.% ZrO2. The occurrence of Zr-arfvedsonite (and of Zr-aegirine) in interstitial patches suggests that variably trace element-enriched domains existed within the residual melts on very small scales.
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Rosenthal, Adam R. "Love of Life: Deconstruction, Biotech & the Survival of Indefinite Life." Oxford Literary Review 40, no. 2 (December 2018): 156–80. http://dx.doi.org/10.3366/olr.2018.0250.
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Derrida's concept of survival, born out of Benjamin's work on translation in The Task of the Translator, has become a fixed element of readings of his work in recent years. Of particular interest in his final seminars on The Beast and the Sovereign and The Death Penalty, survival might be said to do to the concept of life what writing had done to that of speech. In this essay, I explore how the Derridean concept of survival, far from excluding dreams of immortality, in fact opens them. By putting deconstruction into contact with biotechnological fantasies of brain uploading and biological immortality, this essay asks what deconstruction's love of life might be able to teach us about the desire for immortal life in general, and biotechnological ventures, such as Dmitri Itskov's 2045 Initiative, in particular.
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Keppie, J. Duncan, and R. D. Dallmeyer. "40Ar/39Ar mineral ages from Kellys Mountain, Cape Breton Island, Nova Scotia: implications for the tectonothermal evolution of the Avalon composite terrane." Canadian Journal of Earth Sciences 26, no. 8 (August 1, 1989): 1509–16. http://dx.doi.org/10.1139/e89-129.
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Hornblende from a diorite stock within the Kellys Mountain plutonic complex within the Avalon composite terrane, and hornblende, muscovite, and biotite from amphibolite and gneiss within the contact aureole record similar 40Ar/39Ar plateau ages of 493–498 Ma. These data indicate relatively rapid cooling through the contrasting temperatures appropriate for intracrystalline retention of argon in the different minerals. This is consistent with the relatively high level of intrusion of the pluton (3–10 km) suggested previously from the study of mineral assemblages developed in the contact aureole. These relationships suggest that intrusion of the Kellys Mountain complex took place at approximately 500 Ma, indicating an age close to the Cambro-Ordovician boundary. The complex may have formed in the same within-plate rifting regime as the Middle Cambrian Bourinot Group volcanic sequences exposed within the Avalon composite terrane.
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Graham, N. T., M. Feely, and B. Callaghan. "Plagioclase-rich microgranular inclusions from the late-Caledonian Galway Granite, Connemara, Ireland." Mineralogical Magazine 64, no. 1 (February 2000): 113–20. http://dx.doi.org/10.1180/002646100549030.
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AbstractWe report on the occurrence, petrology and geochemistry of recently recognized leucocratic plagioclase-rich microgranular inclusions hosted by two granite facies in the late-Caledonian Galway Granite, Connemara, Ireland. They have been recorded at 66 localities along an ESE trending, 4 km wide corridor which incorporates the contact zone between their host granites (i.e. The Megacrystic Granite and the Mingling and Mixing Zone Granodiorite). The inclusions are discoidal in shape and oriented parallel to the general ESE trending foliation in the granites with the most elongate (6.0 × 0.6 cm) occurring in zones of strongest fabric intensity. Contacts between the inclusions and the host granite are sharp with no chilled margin visible. They display a fine-grained (<1 mm) interlocking texture with occasional crystals of plagioclase ranging up to 2 mm in length. Microprobe analysis shows that the plagioclase is essentially oligoclase (An22–32) in composition and is similar to that (i.e. An21–30) occurring in the host granites. Furthermore, the oligoclase accounts for between 61 and 78% of the mode which is reflected in the major element chemistry of the inclusions. Other minerals (in decending order of abundance) include K-feldspar, quartz, biotite and magnetite. The origin of the inclusions is unclear. However, the results of the microprobe analysis provide evidence of a link between them and their host granites.
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Yuan, Jiaxin, Qingye Hou, Zhongfang Yang, Zhaochu Hu, and Tao Yu. "LA-ICP-MS Analysis of Minerals from the Shizhuyuan W-Polymetallic Deposit, South China: Implications for Mineralization of Pb, W, Mo and Bi." Minerals 10, no. 9 (August 24, 2020): 748. http://dx.doi.org/10.3390/min10090748.
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The South China Block (SCB) is a globally important metallogenic district containing numerous W-Sn deposits. Extensive studies of W-polymetallic deposits in this region have greatly improved our understanding of the petrogenesis, geochronology and metallogenesis of these systems. However, studies on the mobilization of ore-forming elements between mineralization- and alteration-related minerals using in situ analyses are rare. Using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), we analyzed W, Pb, Mo and Bi concentrations in silicate minerals and scheelite from granites and skarns associated with the Shizhuyuan W-polymetallic deposit in the Nanling Range in the SCB. Data show that muscovitized biotite in granites contains high W contents. Pb mainly occurs in K-feldspar and plagioclase in granites and epidote and scheelite in skarns. Bi mainly occurs in epidote in skarns. Scheelite in skarns contains high W and Mo contents. Pb isomorphously substitutes K or Ca in silicate minerals and scheelite. W isomorphously substitutes Ti in biotite. Mo isomorphously substitutes W in scheelite and occurs as W-bearing submicroscopic inclusions in minerals with low contents. Bi isomorphously substitutes Pb when the Pb content is relatively high and occurs as Bi-bearing micro or submicroscopic inclusions in minerals when the Pb content is low. Biotite and feldspar are altered in a magmatic-hydrothermal process, W enriched in biotite, Pb enriched in feldspar and the W-, Pb-, Mo- and Bi-bearing submicroscopic inclusions are excluded from minerals and released to the magmatic-hydrothermal fluids. Large amounts of W are precipitated in scheelite when the fluids come in contact with carbonate rocks to form skarn, while a few contents of Pb, Mo and Bi are distributed in skarn minerals. Thus, large amounts of Pb, Mo, Bi and residual W remain in the fluids, which results in the formation of a W-Sn-Mo-Bi massive skarn ore.
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Macey, P. H., R. J. Thomas, H. P. Smith, D. Frei, and P. J. le Roux. "Lithostratigraphy of the Naros Granite (Komsberg Suite), South Africa and Namibia." South African Journal of Geology 124, no. 3 (September 1, 2021): 795–804. http://dx.doi.org/10.25131/sajg.124.0040.
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Abstract The Naros Granite occurs as a large, northwest-trending ovoid batholith roughly 30 km long and 15 km wide straddling the Orange River border between South Africa and Namibia, 25 km northeast of Onseepkans. It consists mainly of a leucocratic to mesocratic grey, coarse-grained equigranular hornblende-biotite granite-granodiorite that is locally mildly feldspar porphyritic. Small, ovoid mafic autoliths are common and characteristic of the Naros Granite. The composition of the unit varies from granite to granodiorite with a minor leucogranitic phase observed along the southern margin of the batholith. Hornblende and biotite are ubiquitous mafic minerals but small amounts of orthopyroxene occur locally. The Naros Granite has yielded tightly-constrained U-Pb zircon ages between 1 114 Ma and 1 101 Ma. The Naros Granite is generally unfoliated to weakly deformed with only localised shearing along contacts with the surrounding country rocks giving rise to orthogneissic fabrics. It has an intermediate to felsic composition (mean SiO2: 63.9 ± 2.2 wt.%) and is strongly metaluminous. This, together with its biotite-hornblende ± orthopyroxene mineral assemblage and the abundance of mafic autoliths, suggests it is an I-type granitoid, with the source magma produced by partial melting of older igneous rocks that had not undergone any significant chemical weathering. The Naros Granite is the youngest and most evolved member of the ~1.11 Ga Komsberg Suite, a collection of late- to post-tectonic I-type metaluminous, intermediate to felsic, biotite ± hornblende granitoids and their charnockitic equivalents that have intruded the older pre-tectonic gneisses of the Kakamas Domain of the Namaqua Metamorphic Sector.
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Searle, M. P., M. B. Crawford, and A. J. Rex. "Field relations, geochemistry, origin and emplacement of the Baltoro granite, Central Karakoram." Transactions of the Royal Society of Edinburgh: Earth Sciences 83, no. 3 (1992): 519–38. http://dx.doi.org/10.1017/s0263593300005861.
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AbstractThe Miocene Baltoro granite forms a massive plutonic unit within the Karakoram batholith, and is composed of comagmatic monzogranites and leucogranites with a mineralogy consisting of quartz-K-feldspar-plagioclase-biotite ± muscovite ± garnet, with accessory sphene, zircon, monazite and opaques. Geochemically the Baltoro granites are mildly peraluminous, and show a calc-alkaline trend on trace-element normalised diagrams with high LIL/HFS element ratios and negative Nb, P and Ti anomalies. REE are strongly fractionated with little or no Eu anomaly. Leucogranites are depleted in most elements compared to monzogranites with notable exceptions being Rb, K and the HREEs. Initial 87Sr/86Sr ratios are 0·7072-0·7128, considerably lower than High Himalayan leucogranites (0·74-0·79), and are indicative of a lower continental crust source. The probable petrogenesis of the Baltoro granite involves dehydration melting of a biotite-rich pelite to produce a voluminous, hot, water-undersaturated magma which could then separate from its source and intrude through an already thickened and still hot crust. Fractional crystallisation of the monzogranites produced the leucogranites and a pegmatite dyke swarm. A suite of lamprophyre dykes including amphibolerich vogesites and biotite-rich minettes intrude the country rock, dominantly to the north, around the Baltoro granite. These calc-alkaline shoshonitic lamprophyres are volatile-rich mantle-derived melts intruded around the same time as the granite, indicating simultaneous melting of the mantle and lower crust beneath the Karakoram during the Miocene, approximately 30 Ma after the India-Asia collision which initially caused the crustal thickening. Intrusion of mantle melts provided heat to promote crustal melting and may have selectively contaminated the granite magma.The Baltoro granite intrudes sillimanite gneisses with melt pods along the southern margin indicating temperatures above 700°C at the time of intrusion. Locally, internal fabrics and numerous aligned xenoliths along the southern margin in the Biafo glacier region indicate steep, southward-directed thrusting during emplacement. Along the northern contact, the Baltoro granite intrudes anchimetamorphic to greenschist facies metasedimentary rocks with an andalusite-bearing contact aureole. Northward-directed culmination collapse normal faulting during Miocene emplacement is inferred, in order to explain the P-T differences either side of the pluton. This also provided an extensional stress regime in the upper crust to accommodate the rising magma.
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Ellis, D. J., and M. Obata. "Migmatite and melt segregation at Cooma, New South Wales." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 83, no. 1-2 (1992): 95–106. http://dx.doi.org/10.1017/s0263593300007781.
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ABSTRACTThe Cooma Complex of southeastern New South Wales comprises an andalusite-bearing S-type granodiorite surrounded by migmatites and low-pressure metamorphosed pelitic and psammitic sediments. The migmatite formed by the melting reaction:Biotite + Andalusite + K-feldspar + Quartz + V = Cordierite + Liquidat about 350–400 MPa , 670-730°C.The melanosome consists of biotite + cordierite + andalusite + K-feldspar + plagioclase + quartz + ilmenite, whereas the leucosome consists of cordierite + K-feldspar + quartz with extremely rare biotite and plagioclase. In a closed system, freezing of the leucosome melt patches should have resulted in cordierite back-reaction with melt to produce biotite and andalusite. The virtually anhydrous mineralogy of the leucosome patches, lack of cordierite reaction and the absence of biotite selvedges at the leucosome-melanosome contacts, indicates that the melt did not completely solidify in situ. These observations can be explained by an initial peritectic melting reaction in the migmatite being arrested from back-reaction upon cooling because of the removal of hydrous melt, enabling leucosome cordierite to escape back-reaction. We propose that the melanosome is the residue of partial melting but that the leucosome patches do not represent frozen melt segregations but rather the liquidus minerals (cumulates) which precipitated from the melt.In the restite-rich granodiorite from the core of the Cooma Complex, cordierite of similar composition to that in the migmatite has reaction rims of biotite and andalusite and there are coexisting biotite and andalusite in the matrix. The granodiorite consisted of about 50 wt% melt together with resite biotite, quartz and plagioclase, which can possibly be identified in the surrounding migmatite. Previous work suggested that the Cooma Granodiorite can be derived from a mixture of the surrounding metasediments which are of similar composition in the high and low-grade areas surrounding the granodiorite. Re-examinatibn of those data shows that the high-grade metasediments are more An-rich than the low-grade rocks. The Cooma Granodiorite is very similar to the high-grade rocks in terms of Or-Ab-An ratio. This suggests derivation of the Cooma Granodiorite from the high-grade rocks and not from the relatively An-poor low-grade rocks which are typical of exposed sediments in the Lachlan Fold Belt. It is most likely that the granodiorite and envelope of high-grade rocks have been emplaced into the compositionally different lower grade rocks from slightly greater depths.
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Plougarlis, Anastasios, Markos Tranos, and Lambrini Papadopoulou. "The tectonostratigraphic architecture of the Serbo-Macedonian massif in the Vertiskos and Kerdilion mountains (Northern Greece)." Bulletin of the Geological Society of Greece 57, no. 1 (March 24, 2021): 1. http://dx.doi.org/10.12681/bgsg.25054.
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The lithologies and structural features of the exposed rocks of the Serbo-Macedonian massif in the Vertiskos and Kerdilion Mts. have been studied in detail by carrying out km-long cross-sections. Moreover, a new tectonostratigraphic architecture for the massif is proposed, based on the migmatization and anatexis that the rocks pertain, under which the specific exposed rocks have been placed into the Vertiskos and Kerdilion Units. The latter approach differs from the traditional view, which is based solely on the lithological difference between the units. In particular, in the Vertiskos Mt., mica schists, garnet-bearing two-mica gneisses, and predominantly two-mica gneisses, without a sign of anatexis and migmatization, overlie tectonically, biotite gneisses and layered amphibolite gneisses into which migmatization and anatexis takes place. The former constitute the Vertiskos Unit, whereas the latter have been grouped into the Kerdilion Unit, since they are of similar lithologies and affinities with rocks of the Kerdilion Unit. The Kerdilion Mt. is a large antiform made up of biotite gneisses alternating with marbles, which are similarly characterized by intense migmatization and anatexis. These rocks are intruded by the Oreskia granite, which is foliated and follows the general trend of the country rocks. All the rocks are folded with isoclinal to tight folds, and the contact between the two units is a mylonitic shear zone with a top-to-the-SW sense-of-shear. Also, a large volume of ultramafic rocks occurs between the Vertiskos and Kerdilion Mts., including metamorphosed rocks like metagabbros to massive amphibolites, which is assigned to the Therma-Volvi-Gomati Complex (TVGC). These rocks have been found in tectonic contact, i.e., shear zones with top-to-the-SW sense-of-shear, only with the rocks of the Kerdilion Unit. Taking into account our new tectonostratigraphic architecture, the contact between the Vertiskos and Kerdilion Units is not located along the western side of the marbles, as the latter are exposed in the Kerdilion Mt. It is traced westerly in the Vertiskos Mt. dipping with intermediate angles towards the SW, due to NW-trending, map-scale, isoclinal folding. The ultramafic rocks of the TVGC are in tectonic contact with the rocks of the Kerdilion Unit, but not the two-mica gneisses of the Vertiskos Unit, and the Arnea granite intrudes not only the Vertiskos Unit as previously considered, but the rocks of the Kerdilion Unit, as well.
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Soria, Carlos A. "Bioterr Labitech, un nuevo fitonematicida a base de benzimidazol." Revista Ecuatoriana de Medicina y Ciencias Biológicas 30, no. 1-2 (July 10, 2017): 28. http://dx.doi.org/10.26807/remcb.v30i1-2.71.
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Se estudió el efecto del Bioterr Labitech, un nuevo fitonematicida a base de benzimidazol, como una alternativa al uso de nematicidasorganofosforados y clorinados. Se utilizaron varios cultivos comerciales para demostrar, primero, la incidencia de diferentes géneros denematoparásitos en dichas plantaciones, y segundo, el control de los mismos utilizando diferentes dosificaciones, únicas o repetitivas,del producto. No se reportó fitotoxicidad en banano (Musaparadisiaca), tomate de árbol(Solanum betaseum), rosas(Rosasp.) y tomate riñón(Solanum lycopersicum), inclusive utilizando dosis por encima de las recomendadas. En los suelos de los rosales estudiados, se encontró principalmente Meloidogyne, Paratylenchusy Pratylenchus, como los más numerosos. El Bioterr redujo el número de nemátodos del suelo en rosas y tomate de árbol a niveles considerados fitopatológicamente tolerables. También hubo disminución parasitaria en las agallas radiculares causadas por Meloidogynesp. El control dentro de las agallas parece indicar que el producto actúa, no solamente por contacto externo fuera de la raíz con parásitos libres, sino también en forma sistémica con los endoparásitos. Se reporta diferencias significativas en la sensibilidad parasitaria comparada con los saprófitos que resultan menos afectados. Se anota esta diferencia considerando la importancia de estos últimos en el mantenimiento del equilibrio bioquímico de los suelos.
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McMaster, T. J., M. M. Smits, S. J. Haward, J. R. Leake, S. Banwart, and K. V. Ragnarsdottir. "High-resolution imaging of biotite dissolution and measurement of activation energy." Mineralogical Magazine 72, no. 1 (February 2008): 115–20. http://dx.doi.org/10.1180/minmag.2008.072.1.115.
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AbstractWe have used a direct imaging technique, in situ atomic force microscopy(AFM) to observe the earliest stages of the dissolution of a biotite surface byoxalic acid at temperatures close to ambient conditions, using a speciallydesigned AFM liquid cell and non-invasive intermittent contact mode of operation. From the nm-resolution data sets in x, yand z dimensions, we have measured dissolution rates and determined activation energies for the process as a function of temperature, via a mass-loss calculation. The value of Ea obtained, 49±2 kJ mol-1, appears to be too high to indicate a diffusion-controlled process and is more in line with expectations based on a process limited by the rate of ligand-induced metal cation detachment from the (001) surface. This is consistent with visual observations of the relative rates of etch-pit formation and growth, and accepted knowledge of the biotite crystal structure. Separate calculations based on planar area etch-pit growth, and measurements of etch-pit perimeters confirm this result, and also indicate substantiallyhigher activation energy, up to 80 kJ mol-1, when the edge pits are in an incipient stage.
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Lee, Jeong, Tae-Eung Sung, Eungdo Kim, and Kwangsoo Shin. "Evaluating Determinant Priority of License Fee in Biotech Industry." Journal of Open Innovation: Technology, Market, and Complexity 4, no. 3 (August 2, 2018): 30. http://dx.doi.org/10.3390/joitmc4030030.
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This research aimed to build a solid basis through analytic hierarchy process (AHP) analysis to develop a reliable and practical valuation model that reflects the characteristics of the biotech industry and propose a reference formula to estimate the license fee by drug class for potential business transactions. In this study, we reviewed 135 related studies and found 167 related determinants. We surveyed 25 or more specialists in the biopharmaceutical industries. The survey group consisted of National Research Institutes (‘Group 1’), Companies (‘Group 2’), and Government Agencies–Universities (‘Group 3’). The average of the total group and Group 3 showed the same tendency at a Level 3 ranking, where the priority in determining the license fee was arranged in the order of ‘the market factor, the technology factor, the financial factor, and the environmental factor’ in light of the factors, and ‘patent characteristics, licensee characteristics, and licensor characteristics’ for the characteristics. We noted that the patent characteristics were primarily significant in technology transactions and their contract fee in the groups (Total, Group 2 and Group 3), followed by licensee characteristics. In terms of the in-depth index, we noted that the development phase and attrition rate, intellectual property tradability, and licensee licensing experience, followed by quality of technology, were the most influential determinants.
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Neofotistos, Petros Georgios, Markos Damianos Tranos, and Renée Heilbronner. "Geology and deformation of the Serbo-Macedonian massif in the northern part of the Athos Peninsula, Northern Greece: Insights from two detailed cross-sections." Bulletin of the Geological Society of Greece 56, no. 1 (July 21, 2020): 167. http://dx.doi.org/10.12681/bgsg.22529.
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The Athos peninsula occupies the south-eastern part of the wider Chalkidiki peninsula in Central Macedonia, Greece. It is mainly built up by crystalline rocks belonging to the Serbo-Macedonian massif, traditionally constituting, along with the Rhodope massif, the Hellenic hinterland. According to the basic geological map of the peninsula, its northern part is mainly composed of marbles grouped into the Kerdyllion Unit, and biotite gneisses and two-mica gneisses grouped into the Vertiskos Unit of the Serbo-Macedonian massif, whereas the contact between the units is considered as a normal contact, although it has been re-evaluated as tectonic later on. Moreover, amphibolites and ultramafic rocks exist along with the previously mentioned rocks, making the geology and relationship between the two units much more complicated. Two detailed cross-sections and structural analysis permit us to revise the geology of the region concluding that the marbles, the amphibolite gneisses, formerly independent amphibolites, and the biotite gneisses belong to the Kerdyllion Unit that is strongly characterized by migmatization and anatexis, whereas the Vertiskos Unit is represented predominantly by two-mica gneisses that were not extensively, if at all, affected by these phenomena. Isoclinal folding and intense shearing with an overall top-to-the-S sense of shear resulted in the main fabric of the rocks and the mylonitic shear zone between the units. More importantly, the two-mica gneiss of the Vertiskos Unit is sandwiched between the rocks of the Kerdyllion Unit. We attribute both isoclinal folding and shearing to a Mesozoic tectonic event associated with an amphibolite facies metamorphism, leading to an Alpine reworking of the Serbo-Macedonian massif. This Alpine reworking continues during Eocene times with an ENE-WSW compression, giving rise to asymmetric to inverted folds, co-axially refolding pre-existing fabrics and structures. Our work strongly suggests that the overall structure and tectono-stratigraphy concerning the Vertiskos and Kerdyllion Units as well as the contact between them should not be based on the existence of the marbles, as traditionally followed up till now, but on the migmatization and anatexis processes that are almost absent from the rocks of the Vertiskos Unit.
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O'Connor, P. J., and C. B. Long. "Radioelement abundance data for some Dalradian rocks from Co. Donegal, Ireland." Mineralogical Magazine 49, no. 354 (December 1985): 643–48. http://dx.doi.org/10.1180/minmag.1985.049.354.02.
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AbstractData for U, Th, and K, determined by epithermal neutron activation methods, are reported for Lower and Middle Dalradian lithologies from Co. Donegal, Ireland. Abundances are identical to rocks with stratigraphical correlation in the Scottish Dalradian and appear not to have been affected by regional metamorphism to biotite and possibly even garnet grade during the Grampian orogenic phase, or later contact metamorphism in the aureole of the Main Donegal pluton. Uraniferous Dalradian lithologies have not been encountered in Donegal. Incorporation of Dalradian rocks, either by assimilation or as extensive raft trains within the Main Donegal granite, is therefore unlikely to have contributed to the development of known pegmatite-hosted U mineralization associated with this late Caledonian pluton.
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Sharma, Ram S., Jane D. Sills, and M. Joshi. "Mineralogy and metamorphic history of norite dykes within granulite facies gneisses from Sand Mata, Rajasthan, NW India." Mineralogical Magazine 51, no. 360 (June 1987): 207–15. http://dx.doi.org/10.1180/minmag.1987.051.360.03.
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AbstractMetanorite dykes intrude the Banded Gneiss Complex at various places in Rajasthan, N.W. India. They show neither chilled margins nor gradational contacts with the country rock amphibolite or granulite facies gneisses. They have ophitic to subophitic texture with strongly zoned subcalcic clinopyroxene and orthopyroxene, olivine and plagioclase, with subsidiary biotite. During slow cooling a series of reaction coronas developed with garnet forming round biotite, ilmenite and orthopyroxene; hornblende round pyroxenes and orthopyroxene, hornblende ± spinel round olivine, which may be totally replaced. It is inferred that the dykes crystallised from a tholeiitic magma at about 1100-1150 °C and were intruded during the waning stages of granulite facies metamorphism. The corona minerals grew at about 650–700 °C. A series of reactions to account for the development of the coronas is proposed using measured mineral compositions. Although these reactions do not balance for individual corona formation, metamorphism was probably isochemical with Ca, Na, K, Ti, Si and H2O only mobile on the scale of a thin section. Si and H2O were possibly mobile on a larger scale.
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FESTA, VINCENZO, ALFREDO CAGGIANELLI, ANTONIO LANGONE, and GIACOMO PROSSER. "Time–space relationships among structural and metamorphic aureoles related to granite emplacement: a case study from the Serre Massif (southern Italy)." Geological Magazine 150, no. 3 (November 16, 2012): 441–54. http://dx.doi.org/10.1017/s0016756812000714.
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AbstractTectonic and thermal perturbations, related to emplacement of granodiorite in the upper continental crust, have been investigated in the late-Hercynian basement exposed in southern Calabria (Italy). Here, the structural aureole is marked by the presence of a major rim fold adjacent to the intrusive contact for a length of at least 20 km. Geometrical analysis of the structural aureole and related foliations, lineations and crenulations reveals that the perturbed zone is at least 3000 m wide and characterized by an open synform trending nearly parallel to the intrusive contact. This pattern is compatible with a laccolith-like mode of magma emplacement, related to the accretion of the pluton that shouldered weak phyllitic and slaty wall rocks. The metamorphic aureole, about 1800 m wide, is characterized by biotite, cordierite and andalusite that appear sequentially in spotted schists and hornfelses approaching the intrusive contact. The peak assemblage equilibrated between 535 and 590°C at pressures between 175 and 200 MPa, confirmed by Al-in-hornblende barometry on granodiorite. Microstructural analysis allowed the inference of a time lag between the thermal and tectonic perturbations. With the aid of thermal modelling it was possible to quantify the time required to reach the peak temperature at a distance from the intrusive contact where cordierite spots and andalusite porphyroblasts clearly overprint crenulations. This estimate represents the time limit to accomplish deformation in the inner portion of the aureole and thus indicates a minimum strain rate of 4 × 10−14 s−1 within the country rocks during granodiorite intrusion.
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Mónok, Dávid, and György Füleky. "A talaj kadmium szennyezettségének vizsgálata angolperje (Lolium perenne L.) bioteszttel." Agrokémia és Talajtan 66, no. 2 (December 2017): 333–47. http://dx.doi.org/10.1556/0088.2017.66.2.3.
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Cadmium accumulation in soils causes ecological, biological and human health risks. Previous studies have shown that reductions in the shoot height and fresh biomass of ryegrass (Lolium perenne L.) are a sensitive indicator of the cadmium pollution level in soils. Four soils with different types and properties were included in the experiment. In the first period of the biotest, 2 g cotton-wool pads moistened with distilled water were planted with 2 g of perennial ryegrass seeds and the seedlings were grown for 6 days. On the 7th day the cotton-wool pads containing the seedlings were placed on soils polluted with four levels of cadmium: 0, 1, 2 and 4 mg Cd kg−1 soil, added to the soil in the form of cadmium acetate. After a first nutrient-deficient period, the seedlings took up nutrients and toxic substances intensively from the soil samples. After a 14-day period of soil–plant contact the fresh biomass, dry biomass and Cd concentration of the shoots were measured, in addition to which the shoot height was measured every 2 days. Cadmium treatment significantly reduced the shoot height and fresh weight of ryegrass in all the tested soils, and the damaging effect was proportional to the applied dose. A reduction of more than 10% in the shoot height and fresh weight were observed even at a Cd pollution level of 1 mg Cd kg−1 soil. At the highest Cd level the decrease in shoot height was more than 40% and the decrease in fresh weight more than 35% in all the soils. The increasing level of Cd application significantly increased the Cd concentration of the shoots. More Cd was accumulated in ryegrass shoots on soils with low pH and low organic matter content. The results indicate that the ryegrass biotest method is suitable for the characterization of Cd contamination in different soils.
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Liu, Jie, Yue Xin Han, and Wan Zhong Yin. "Research on Process Mineralogy of Potassium-Rich Shale." Advanced Materials Research 158 (November 2010): 197–203. http://dx.doi.org/10.4028/www.scientific.net/amr.158.197.
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The process mineralogy of potassium-rich shale from Chaoyang of Liaoning, China, was studied. Research results showed there are much less variety and smaller quantities in mineral compositions. Calculated mineral composition by means of chemical composition analysis combined with XRD, MLA, IR and TG-DSC analyses showed that main minerals with were Potassium-feldspar, muscovite, biotite and illite, and gangue minerals were quartz and small amounts of hematite. Potassium-rich minerals such as potassium-feldspar and muscovite contact smoothly with quartz respectively, and there was the direction arrangement among potassium-feldspar, quartz and muscovite in the shale. And quartz and hematite were main cement in the shale. The influences of the research results on the potassium extraction from potassium-rich shale were distinct.
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Gruiz, K., A. Murányi, M. Molnár, and B. Horváth. "Risk assessment of heavy metal contamination in Danube sediments from Hungary." Water Science and Technology 37, no. 6-7 (March 1, 1998): 273–81. http://dx.doi.org/10.2166/wst.1998.0762.
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The aim of the current research is to establish a suitable Environmental Risk Assessment (ERA) scheme for Danube sediments in Hungary by determining contaminants' concentrations by chemical analysis and by assessing their ecotoxicological effects. Seventeen sedimentation sites were identified, mainly upstream of Budapest, between river kilometres 1811 and 1586. The heavy metal contents and basic properties of sediments were determined. Excess heavy metal content was used to characterize the extent of heavy metal contamination. Direct contact biotests were developed for testing the toxic effect of contaminated sediments. Ecotoxicological effects were measured by three bacterial tests and one plant bioassay. Effect Concentrations were determined by the inhibition of the bioluminescence of Photobacterium phosphoreum. The resultant inhibition of different partial toxic effects was characterized by Cu equivalent. Chemical and ecotoxicological results were studied together, making it possible to characterize the extent of the pollution and its biological effects at the same time. It was concluded that combined chemical and ecotoxicological characterization of contaminated sediments may serve as a strong basis for assessing the site-specific risk of heavy metal pollution.
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Darling, Ryan, Eric Bonner, and Pei Li. "Workshop on Recent Issues in Bioanalysis (WRIB) Poster Award winners 2019." Bioanalysis 11, no. 24 (December 2019): 2245–49. http://dx.doi.org/10.4155/bio-2019-0263.
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The 13th WRIB was held in New Orleans, LA, USA in April 2019. It drew over 1000 professionals representing large pharmas, biotechs, contract research organizations and multiple regulatory agencies from around the world. The Global Bioanalytical Community convened in New Orleans to discuss current topics of interest in bioanalysis, biomarkers, immunogenicity and gene therapy. High quality, better compliance to regulations and scientific excellence are always the foundations of this workshop. Bioanalysis and Bioanalysis Zone are very proud to be supporting the WRIB Poster Awards again this year, and we feature the profiles of the authors of the winning posters. Visit www.bioanalysis-zone.com to see the winning posters in full.