154 research outputs found

    Lower Coverdale and Gaytons: Middle Devonian and possibly older anorthosite-ferronorite, gabbro, and quartz monzonite intrusions in southeastern New Brunswick

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    The Lower Coverdale intrusion near Moncton, New Brunswick, has been intersected in drill holes at depths of 100–200 m below unconformably overlying Carboniferous sandstone, onglomerate and, locally, limestone of the Windsor, Mabou, and Cumberland groups. A large positive aeromagnetic anomaly suggests that the intrusion has a subsurface area of at least 30–40 km2. As revealed by drill core and cuttings, the intrusion consists of interlayered coarse-grained anorthosite and ferronorite, both intruded by gabbro, quartz monzonite, and minor felsic dykes. The ferronorite is high in Ti and P, and contains interstitial patite and ilmenite/magnetite and layers of apatite-ilmenite rock (nelsonite) up to several metres thick. Much of the core shows pervasive effects of metamorphism and alteration but microprobe analyses of the freshest samples revealed that the plagioclase in both anorthosite and ferronorite has andesine composition. The anorthosite and ferronorite are chemically distinct, but their close spatial association suggests a genetic link. In contrast, the younger gabbroic rocks differ in mineralogy and chemistry from, and appear unrelated to, the anorthosite and ferronorite. They are altered but not metamorphosed, and preserve intergranular textures. They contain more calcic plagioclase and augite, and have low Ti and P. The deepest drill hole in the Lower Coverdale intrusion encountered highly altered coarse-grained quartz monzonite at a depth of 1095–1206 m. The quartz monzonite is mineralogically and chemically similar to quartz monzonite in quarries near Gaytons, 20 km to the east. Virtually identical Middle Devonian U-Pb zircon ages of 90.6 ± 1.0 Ma and 390.0 ± 0.5 Ma were obtained for samples from the Lower Coverdale and Gaytons quartz monzonite, espectively. However, the anorthosite-ferronoritegabbro is likely considerably older: perhaps ca. 540 Ma like gabbroic rocks elsewhere in the Brookville terrane; or possibly esoproterozoic, like intrusions with similar characteristics in Grenvillian parts of the Precambrian shield. RÉSUMÉ On a croisé l’intrusion de Lower Coverdale près de Moncton (Nouveau-Brunswick) dans des puits forés à des profondeurs de 100 à 200 m au-dessous de grès du Carbonifère sus-jacent non concordant, de conglomérat et, par endroits, de calcaire des groupes de Windsor, de Mabou et de Cumberland. Une anomalie aéromagnétique positive étendue permet de supposer que l’intrusion a une superficie souterraine d’au moins 30 à 40 kilomètres carrés. Les carottes de forage et les déblais révèlent que l’intrusion est constituée de ferronorite et d’anorthosite à grains grossiers interstratifiées, toutes deux pénétrées par du gabbro, de l’adamellite et des dykes felsiques secondaires. La ferronorite est riche en Ti et en P et renferme de ’ilménite/magnétite et de l’apatite interstitielles ainsi que des couches d’ilménite-apatite (nelsonite) pouvant avoir plusieurs mètres d’épaisseur. Une vaste part des carottes témoignent des effets intenses d’un métamorphisme et d’une altération, mais des analyses à la microsonde des échantillons les plus frais ont révélé que le plagioclase à l’intérieur de l’anorthosite et de la ferronorite est composé d’andésine. L’anorthosite et la ferronorite sont chimiquement distinctes, mais leur association spatiale étroite laisse supposer un lien génétique. Par contre, les roches gabbroïques plus récentes ont une composition minéralogique et chimique différant de celles de l’anorthosite et de la ferronorite et elles ne semblent pas y être apparentées. Elles sont altérées mais ne sont pas métamorphisées et elles conservent des textures intergranulaires. Elles renferment plus de plagioclase calcique et d’augite et ont une faible teneur en Ti et en P. Le puits de forage le plus profond dans l’intrusion de Lower Coverdale a recoupé de l’adamellite à grains grossiers fortement altérée à une profondeur de 1 095 à 1 206 m. L’adamellite est minéralogiquement et chimiquement similaire à l’adamellite des carrières situées près de Gaytons, à 20 kilomètres à l’est. On a obtenu des datations U-Pb sur zircon pratiquement identiques du Dévonien moyen de 390,6 ± 1,0 Ma et de 390,0 ± 0,5 Ma d’échantillons d’adamellite de Lower Coverdale et de Gaytons, respectivement. Le gabbro l’anorthosite-ferronorite, toutefois, est probablement beaucoup plus âgé : il a peut-être 540 Ma, comme les roches gabbroïques d’ailleurs à l’intérieur du terrane de Brookville, ou il pourrait remonter au Mésoprotérozoïque, comme les intrusions présentant des caractéristiques analogues dans les parties grenvilliennes du bouclier précambrien

    Generation of Boundary Manikin Anthropometry

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    The purpose of this study was to develop 3D digital boundary manikins that are representative of the anthropometry of a unique population. These digital manikins can be used by designers to verify and validate that the components of the spacesuit design satisfy the requirements specified in the Human Systems Integration Requirements (HSIR) document. Currently, the HSIR requires the suit to accommodate the 1st percentile American female to the 99th percentile American male. The manikin anthropometry was derived using two methods: Principal Component Analysis (PCA) and Whole Body Posture Based Analysis (WBPBA). PCA is a statistical method for reducing a multidimensional data set by using eigenvectors and eigenvalues. The goal is to create a reduced data set that encapsulates the majority of the variation in the population. WBPBA is a multivariate analytical approach that was developed by the Anthropometry and Biomechanics Facility (ABF) to identify the extremes of the population for a given body posture. WBPBA is a simulation-based method that finds extremes in a population based on anthropometry and posture whereas PCA is based solely on anthropometry. Both methods yield a list of subjects and their anthropometry from the target population; PCA resulted in 20 female and 22 male subjects anthropometry and WBPBA resulted in 7 subjects' anthropometry representing the extreme subjects in the target population. The subjects anthropometry is then used to 'morph' a baseline digital scan of a person with the same body type to create a 3D digital model that can be used as a tool for designers, the details of which will be discussed in subsequent papers

    Prospectus, January 14, 1991

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    https://spark.parkland.edu/prospectus_1991/1000/thumbnail.jp

    Time-Dependent Point Source Search Methods in High Energy Neutrino Astronomy

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    We present maximum-likelihood search methods for time-dependent fluxes from point sources, such as flares or periodic emissions. We describe a method for the case when the time dependence of the flux can be assumed a priori from other observations, and we additionally describe a method to search for bursts with an unknown time dependence. In the context of high energy neutrino astronomy, we simulate one year of data from a cubic-kilometer scale neutrino detector and characterize these methods and equivalent binned methods with respect to the duration of neutrino emission. Compared to standard time-integrated searches, we find that up to an order of magnitude fewer events are needed to discover bursts with short durations, even when the burst time and duration are not known a priori.Comment: LaTeX; 17 Pages, 4 figures; submitted to Astroparticle Physic

    The Ursinus Weekly, April 29, 1971

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    Hermann F. Eilts addresses Ursinus • New Weekly staff named; Charles L. Chambers, editor • Pi Gamma Mu elects new president, Dr. Eugene Herbert Miller of Ursinus, at their annual national board meeting • Cub and Key Society names new members • The Myrin Library dedication set for Sunday, May 22, 1971 • Editorial: Statement of purpose • No psychologist this year, administration tells SFARC • Campus perspective: Changing with the times • Marchers invade Washington for week of demonstrations • Editorial: Before you march • Letters to the editor: Eating in garbage; Sex objects • Ecology crushes UC apathy as recycling days continue • Academic committee studies curriculum • Faculty suggest change in eligibility of students • Showboat to highlight Spring I.F. weekend • A marathon that wasn\u27t : Freshmen still determined • Wilma Scott Heide of N.O.W. talks of women\u27s liberation • Chancellor Helfferich to direct the Campus Chest presentation • Movie critic: Ryan\u27s daughter • Albert and trio prove victorious • Tennis team starts slow; Bears find winning ways • Golf tees off; Squad now 3-5https://digitalcommons.ursinus.edu/weekly/1144/thumbnail.jp

    Prospectus, November 9, 1990

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    https://spark.parkland.edu/prospectus_1990/1025/thumbnail.jp

    Quantified effect of seawater biogeochemistry on the temperature dependence of sea spray aerosol fluxes

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    Future change in sea surface temperature may influence climate via various air-sea feedbacks and pathways. In this study, we investigate the influence of surface seawater biogeochemical composition on the temperature dependence of sea spray number emission fluxes. Dependence of sea spray fluxes was investigated in different water masses (i.e. subantarctic, subtropical and frontal bloom) with contrasting biogeochemical properties across a temperature range from ambient (13&ndash;18 &deg;C) to 2 &deg;C, using seawater circulating in a plunging jet sea spray generator. We observed sea spray total concentration to increase significantly at temperatures below 8 &deg;C, with an average 4-fold increase at 2 &deg;C relative to initial concentration at ambient temperatures. This temperature dependence was more pronounced for smaller size sea spray particles (i.e. nucleation and Aitken modes). Moreover, temperature dependence varied with water mass type and so biogeochemical properties. While the sea spray flux at moderate temperatures (8&ndash;11 &deg;C) was highest in frontal bloom waters, the effect of low temperature on the sea spray flux was highest with subtropical seawaters. The temperature dependence of sea spray flux was also inversely proportional to the seawater cell abundance of the cyanobacterium Synechococcus, which facilitated parameterization of temperature dependence of sea spray emission fluxes as a function of Synechococcus for future implementation in modelling exercises.</p

    Prospectus, September 6, 1989

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    https://spark.parkland.edu/prospectus_1989/1018/thumbnail.jp
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