Reducing zero-point systematics in dark energy supernova experiments     

L. Faccioli  A.G. Kim  R. Miquel  G. Bernstein  A. Bonissent  M. Brown  W. Carithers  J. Christiansen  N. Connolly  S. Deustua  D. Gerdes  L. Gladney  G. Kushner  E.V. Linder  S. McKee  N. Mostek  H. Shukla  A. Stebbins  C. Stoughton  D. Tucker 《Astroparticle Physics》2011,34(12):847-857

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Calibrating photometric redshifts of luminous red galaxies     

Nikhil Padmanabhan  Tamás Budavári  David J. Schlegel  Terry Bridges  Jonathan Brinkmann  Russell Cannon  rew J. Connolly  Scott M. Croom  István Csabai  Michael Drinkwater  Daniel J. Eisenstein  Paul C. Hewett  Jon Loveday  Robert C. Nichol  Kevin A. Pimbblet  Roberto De Propris  Donald P. Schneider  Ryan Scranton  Uro&#; Seljak  Tom Shanks  István Szapudi  Alexander S. Szalay  David Wake 《Monthly notices of the Royal Astronomical Society》2005,359(1):237-250

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Short-term response of estuarine sandflat trophodynamics to pulse anthropogenic physical disturbance: Support for the Intermediate Disturbance Hypothesis     

Ka-Man Lee  S.Y. Lee  Rod M. Connolly 《Estuarine, Coastal and Shelf Science》2011,92(4):414

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Extraterrestrial organic compounds and cyanide in the CM2 carbonaceous chondrites Aguas Zarcas and Murchison     

Jos C. Aponte  Hannah L. McLain  Danielle N. Simkus  Jamie E. Elsila  Daniel P. Glavin  Eric T. Parker  Jason P. Dworkin  Dolores H. Hill  Harold C. Connolly  Dante S. Lauretta 《Meteoritics & planetary science》2020,55(7):1509-1524

Evaluating the water‐soluble organic composition of carbonaceous chondrites is key to understanding the inventory of organic matter present at the origins of the solar system and the subsequent processes that took place inside asteroid parent bodies. Here, we present a side‐by‐side analysis and comparison of the abundance and molecular distribution of aliphatic amines, aldehydes, ketones, mono‐ and dicarboxylic acids, and free and acid‐releasable cyanide species in the CM2 chondrites Aguas Zarcas and Murchison. The Aguas Zarcas meteorite is a recent fall that occurred in central Costa Rica and constitutes the largest recovered mass of a CM‐type meteorite after Murchison. The overall content of organic species we investigated was systematically higher in Murchison than in Aguas Zarcas. Similar to previous meteoritic organic studies, carboxylic acids were one to two orders of magnitude more abundant than other soluble organic compound classes investigated in both meteorite samples. We did not identify free cyanide in Aguas Zarcas and Murchison; however, cyanide species analyzed after acid digestion of the water‐extracted meteorite mineral matrix were detected and quantified at slightly higher abundances in Aguas Zarcas compared to Murchison. Although there were differences in the total abundances of specific compound classes, these two carbonaceous chondrites showed similar isomeric distributions of aliphatic amines and carboxylic acids, with common traits such as a complete suite of structural isomers that decreases in concentration with increasing molecular weight. These observations agree with their petrologic CM type‐2 classification, suggesting that these meteorites experienced similar organic formation processes and/or conditions during parent body aqueous alteration.  相似文献   

Diamond formation episodes at the southern margin of the Kaapvaal Craton: Re–Os systematics of sulfide inclusions from the Jagersfontein Mine     

Sonja Aulbach  Steven B. Shirey  Thomas Stachel  Steven Creighton  Karlis Muehlenbachs  Jeff W. Harris 《Contributions to Mineralogy and Petrology》2009,157(4):525-540

Sulfide inclusions in diamonds from the 90-Ma Jagersfontein kimberlite, intruded into the southern margin of the Kaapvaal Craton, were analyzed for their Re–Os isotope systematics to constrain the ages and petrogenesis of their host diamonds. The latter have δ¹³C ranging between −3.5 and −9.8‰ and nitrogen aggregation states (from pure Type IaA up to 51% total N as B centers) corresponding to time/temperature history deep within the subcontinental lithospheric mantle. Most sulfides are Ni-poor ([Ni + Co]/Fe = 0.05–0.25 for 15 of 17 inclusions), have elevated Cu/[Fe + Ni + Co] ratios (0.02–0.36) and elemental Re–Os ratios between 0.5 and 46 (12 of 14 inclusions) typical of eclogitic to more pyroxenitic mantle sources. Re–Os isotope systematics indicate two generations of diamonds: (1) those on a 1.7 Ga age array with initial ¹⁸⁷Os/¹⁸⁸Os (¹⁸⁷Os/¹⁸⁸Os_i) of 0.46 ± 0.07 and (2) those on a 1.1 Ga array with ¹⁸⁷Os/¹⁸⁸Os_i of 0.30 ± 0.11. The radiogenic initial Os isotopic composition for both generations of diamond suggests that components with high time-integrated Re–Os are involved, potentially by remobilization of ancient subducted oceanic crust and hybridization of peridotite. A single sulfide with higher Os and Ni content but significantly lower ¹⁸⁷Os/¹⁸⁸Os hosted in a diamond with less aggregated N may represent part of a late generation of peridotitic diamonds. The paucity of peridotitic sulfide inclusions in diamonds from Jagersfontein and other kimberlites from the Kaapvaal craton contrasts with an overall high relative abundance of diamonds with peridotitic silicate inclusions. This may relate to extreme depletion and sulfur exhaustion during formation of the Kaapvaal cratonic root, with the consequence that in peridotites, sulfide-included diamonds could only form during later re-introduction of sulfur.  相似文献   

Interplay between tectonic, fluvial and erosional processes along the Western Border Fault of the northern Upper Rhine Graben, Germany   总被引：3，自引：1，他引：3  

Gwendolyn Peters  Thies J. Buchmann  Peter Connolly  Ronald T. van Balen  Friedemann Wenzel  Sierd A.P.L. Cloetingh 《Tectonophysics》2005,406(1-2):39-66

The northern Upper Rhine Graben, situated in the central part of the European Cenozoic rift system, is currently characterized by low intra-plate seismicity. Historical earthquakes have not been large enough to produce surface rupturing. Moreover, the records of Quaternary surface processes and human modifications are presumably better preserved than the record of the relatively slow tectonic deformation.In order to gain information on the neotectonic activity and paleoseismicity in this setting, the geological and geomorphological records of fault movements along a segment of the Western Border Fault (WBF) were studied using an integration of techniques in paleoseismology, structural analysis and shallow geophysics. The WBF segment investigated follows a 20 km long linear scarp of unclear origin. A series of geophysical measurements were performed and the results suggested that near-surface deformation structures are present at the segments' southern end. Several trenches opened at this location revealed fault structures with consistent extensional style and a maximum vertical displacement of 0.5 m. In one trench, the deformation structures were dated between 19 and 8 ka. Assuming the deformation has been caused by an earthquake, a M_w 6.5 earthquake would be implied. Aseismic deformation would point to a fault creep rate ≥ 0.04 mm/yr.A reconstruction of the sequence of events at the trench site, from Middle Pleistocene to Present, demonstrates that the morphology at the base of the scarp is the result of interplay between tectonic activity and fluvial and erosional processes. At the regional scale, a mixed origin for the WBF scarp is proposed, combining the effects of fluvial dynamics, erosion, regional uplift and localized tectonic activity on the WBF.  相似文献   

Fluid and enthalpy production during regional metamorphism   总被引：3，自引：1，他引：3  

James A. D. Connolly  Alan B. Thompson 《Contributions to Mineralogy and Petrology》1989,102(3):347-366

Models for regional metamorphism have been constructed to determine the thermal effects of reaction enthalpy and the amount of fluid generated by dehydration metamorphism. The model continental crust contains an average of 2.9 wt % water and dehydrates by a series of reactions between temperatures of 300 and 750° C. Large scale metamorphism is induced by instantaneous collision belt thickening events which double the crustal thickness to 70 km. After a 20 Ma time lag, erosion due to isostatic rebound restores the crust to its original thickness in 100 Ma. At crustal depths greater than 10 km, where most metamorphism takes place, fluid pressure is unlikely to deviate significantly from lithostatic pressure. This implies that lower crustal porosity can only be maintained if rock pores are filled by fluid. Therefore, porosities are primarily dependent on the rate of metamorphic fluid production or consumption and the crustal permeability. In the models, permeability is taken as a function of porosity; this permits estimation of both fluid fluxes and porosities during metamorphism. Metamorphic activity, as measured by net reaction enthalpy, can be categorized as endothermic or exothermic depending on whether prograde dehydration or retrograde hydration reactions predominate. The endothermic stage begins almost immediately after thickening, peaks at about 20 Ma, and ends after 40 to 55 Ma. During this period the maximum and average heat consumption by reactions are on the order 11.2·10^–14 W/cm³ and 5.9·10^–14 W/ cm³, respectively. The maximum rates of prograde isograd advance decrease from 2.4·10^–8 cm/s, for low grade reactions at 7 Ma, to 7·10^–10 cm/s, for the highest grade reaction between 45 and 58 Ma. Endothermic cooling reduces the temperature variation in the metamorphic models by less than 7% (40 K); in comparison, the retrograde exothermic heating effect is negligible. Dehydration reactions are generally poor thermal buffers, but under certain conditions reactions may control temperature over depth and time intervals on the order of 1 km and 3 Ma. The model metamorphic events reduce the hydrate water content of the crust to values between 1.0 and 0.4 wt % and produce anhydrous lower crustal granulites up to 15 km in thickness. In the first 60 Ma of metamorphism, steady state fluid fluxes in the rocks overlying prograde reaction fronts are on the order of 5·10^–11 g/cm²-s. These fluid fluxes can be accommodated by low porosities (<0.6%) and are thus essentially determined by the rate of devolitalization. The quantity of fluid which passes through the metamorphic column varies from 25000 g/cm², within 10 km of the base of the crust, to amounts as large as 240000 g/cm², in rocks initially at a depth of 30 km. Measured petrologic volumetric fluid-rock ratios generated by this fluid could be as high as 500 in a 1 m thick horizontal layer, but would decrease in inverse proportion of the thickness of the rock layer. Fluid advection causes local heating at rates of about 5.9·10^–14 W/cm³ during prograde metamorphism and does not result in significant heating. The amount of silica which can be transported by the fluids is very sensitive to both the absolute temperature and the change in the geothermal gradient with depth. However, even under optimal conditions, the amount of silica precipitated by metamorphic fluids is small (<0.1 vol %) and inadequate to explain the quartz veining observed in nature. These results are based on equilibrium models for fluid and heat transport that exclude the possibility of convective fluid recirculation. Such a model is likely to apply at depths greater than 10 km; therefore, it is concluded that large scale heat and silica transport by fluids is not extensive in the lower crust, despite large time-integrated fluid fluxes.  相似文献   

Maps as mediated seeing: Fundamentals of cartography     

Tracy Connolly 《New Zealand geographer》2007,63(3):232-233

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Diamonds and their mineral inclusions from the A154 South pipe, Diavik Diamond Mine, Northwest territories, Canada     

Cara L. Donnelly  Thomas Stachel  Steven Creighton  Karlis Muehlenbachs  Sean Whiteford 《Lithos》2007,98(1-4):160-176

Mineral inclusions recovered from 100 diamonds from the A154 South kimberlite (Diavik Diamond Mines, Central Slave Craton, Canada) indicate largely peridotitic diamond sources (83%), with a minor (12%) eclogitic component. Inclusions of ferropericlase (4%) and diamond in diamond (1%) represent “undetermined” parageneses.

Compared to inclusions in diamonds from the Kaapvaal Craton, overall higher CaO contents (2.6 to 6.0 wt.%) of harzburgitic garnets and lower Mg-numbers (90.6 to 93.6) of olivines indicate diamond formation in a chemically less depleted environment. Peridotitic diamonds at A154 South formed in an exceptionally Zn-rich environment, with olivine inclusions containing more than twice the value (of  52 ppm) established for normal mantle olivine. Harzburgitic garnet inclusions generally have sinusoidal rare earth element (REE_N) patterns, enriched in LREE and depleted in HREE. A single analyzed lherzolitic garnet is re-enriched in middle to heavy REE resulting in a “normal” REE_N pattern. Two of the harzburgitic garnets have “transitional” REE_N patterns, broadly similar to that of the lherzolitic garnet. Eclogitic garnet inclusions have normal REE_N patterns similar to eclogitic garnets worldwide but at lower REE concentrations.

Carbon isotopic values (δ¹³C) range from − 10.5‰ to + 0.7‰, with 94% of diamonds falling between − 6.3‰ and − 4.0‰. Nitrogen concentrations range from below detection (< 10 ppm) to 3800 ppm and aggregation states cover the entire spectrum from poorly aggregated (Type IaA) to fully aggregated (Type IaB). Diamonds without evidence of previous plastic deformation (which may have accelerated nitrogen aggregation) typically have < 25% of their nitrogen in the fully aggregated B-centres. Assuming diamond formation beneath the Central Slave to have occurred in the Archean [Westerlund, K.J., Shirey, S.B., Richardson, S.H., Gurney, J.J., Harris, J.W., 2003b. Re–Os systematics of diamond inclusion sulfides from the Panda kimberlite, Slave craton. VIIIth International Kimberlite Conference, Victoria, Canada, Extended Abstracts, 5p.], such low aggregation states indicate mantle residence at fairly low temperatures (< 1100 °C). Geothermometry based on non-touching inclusion pairs, however, indicates diamond formation at temperatures around 1200 °C. To reconcile inclusion and nitrogen based temperature estimates, cooling by about 100–200 °C shortly after diamond formation is required.  相似文献   

An application of the annual egg production method to estimate the spawning biomass of cod (Gadus morhua L.), plaice (Pleuronectes platessa L.) and sole (Solea solea L.) in the Irish Sea   总被引：1，自引：0，他引：1  

Armstrong  M. J.; Connolly  P.; Nash  R. D. M.; Pawson  M. G.; Alesworth  E.; Coulahan  P. J.; Dickey-Collas  M.; Milligan  S. P.; O'Neill  M. F.; Witthames  P. R.; Woolner  L. 《ICES Journal of Marine Science》2001,58(1):183-203

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