37,473 research outputs found
Efficient preservation of young terrestrial organic carbon in sandy turbidity-current deposits
No full text© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Hage, S., Galy, V. V., Cartigny, M. J. B., Acikalin, S., Clare, M. A., Grocke, D. R., Hilton, R. G., Hunt, J. E., Lintern, D. G., McGhee, C. A., Parsons, D. R., Stacey, C. D., Sumner, E. J., & Talling, P. J. Efficient preservation of young terrestrial organic carbon in sandy turbidity-current deposits. Geology, 48(9), (2020): 882-887, doi:10.1130/G47320.1.Burial of terrestrial biospheric particulate organic carbon in marine sediments removes CO2 from the atmosphere, regulating climate over geologic time scales. Rivers deliver terrestrial organic carbon to the sea, while turbidity currents transport river sediment further offshore. Previous studies have suggested that most organic carbon resides in muddy marine sediment. However, turbidity currents can carry a significant component of coarser sediment, which is commonly assumed to be organic carbon poor. Here, using data from a Canadian fjord, we show that young woody debris can be rapidly buried in sandy layers of turbidity current deposits (turbidites). These layers have organic carbon contents 10× higher than the overlying mud layer, and overall, woody debris makes up >70% of the organic carbon preserved in the deposits. Burial of woody debris in sands overlain by mud caps reduces their exposure to oxygen, increasing organic carbon burial efficiency. Sandy turbidity current channels are common in fjords and the deep sea; hence we suggest that previous global organic carbon burial budgets may have been underestimated.We thank C. Johnson, M. Lardie, A. Gagnon, A. McNichol, and the NOSAMS (National Ocean Sciences Accelerator Mass Spectrometry) team (Woods Hole Oceanographic Institution [WHOI], Massachusetts, USA) for their help with ramped oxidation system and isotopes. We thank the captain and crew of CCGS Vector. Support was provided by UK Natural Environment Research Council (NERC) grants NE/M007138/1 (to Cartigny) and NE/L013142/1 (to Talling), NE/P005780/1 and NE/P009190/1 (to Clare); a Royal Society Research Fellowship (to Cartigny); an International Association of Sedimentologists Postgraduate Grant and National Oceanography Centre Southampton–WHOI exchange program funds (to Hage); an independent study award from WHOI (to Galy); the Climate Linked Atlantic Sector Science (CLASS) program (NERC grant NE/R015953/1); and the European Research Council under the European Union’s Horizon 2020 research and innovation program (Grant 725955, to Parsons). We thank François Baudin, Xingqian Cui, editor James Schmitt, and three anonymous reviewers
Cardiac services for care of suspected acute coronary syndromes in Australia and New Zealand hospitals
No full textAbstract 18319Isuru Ranasinghe, Carolyn Astley, Bernadette Aliprandi-Costa, Derek Chew, Christopher J Ellis, Christopher J Hammett, Tom G Briffa, Tegwen E Howell, Karen J Lintern, Hella Parker, Bridie Carr, Greg D Gamble, Rosanna Tavella, Julie Redfern, John French, David Briege
1ST MEASUREMENT OF GAMMA(D(S)(+)-]MU+NU)/GAMMA(D(S)(+)-]PHI-PI+)
No full textComplete Author List:
ACOSTA D, ATHANAS M, MASEK G, PAAR H, BEAN A, GRONBERG J, KUTSCHKE R, MENARY S, MORRISON RJ, NAKANISHI S, NELSON HN, NELSON TK, RICHMAN JD, RYD A, TAJIMA H, SCHMIDT D, SPERKA D, WITHERELL MS, PROCARIO M, YANG S, BALEST R, CHO K, DAOUDI M, FORD WT, JOHNSON DR, LINGEL K, LOHNER M, RANKIN P, SMITH JG, ALEXANDER JP, BEBEK C, BERKELMAN K, BESSON D, BROWDER TE, CASSEL DG, CHO HA, COFFMAN DM, DRELL PS, EHRLICH R, GALIK RS, GARCIASCIVERES M, GEISER B, GITTELMAN B, GRAY SW, HARTILL DL, HELTSLEY BK, JONES CD, JONES SL, KANDASWAMY J, KATAYAMA N, KIM PC, KREINICK DL, LUDWIG GS, MASUI J, MEVISSEN J, MISTRY NB, NG CR, NORDBERG E, OGG M, PATTERSON JR, PETERSON D, RILEY D, SALMAN S, SAPPER M, WORDEN H, WURTHWEIN F, AVERY P, FREYBERGER A, RODRIGUEZ J, STEPHENS R, YELTON J, CINABRO D, HENDERSON S, KINOSHITA K, LIU T, SAULNIER M, SHEN F, WILSON R, YAMAMOTO H, ONG B, SELEN M, SADOFF AJ, AMMAR R, BALL S, BARINGER P, COPPAGE D, COPTY N, DAVIS R, HANCOCK N, KELLY M, KWAK N, LAM H, KUBOTA Y, LATTERY M, NELSON JK, PATTON S, PERTICONE D, POLING R, SAVINOV V, SCHRENK S, WANG R, ALAM MS, KIM IJ, NEMATI B, ONEILL JJ, SEVERINI H, SUN CR, ZOELLER MM, CRAWFORD G, DAUBENMIER CM, FULTON R, FUJINO D, GAN KK, HONSCHEID K, KAGAN H, KASS R, LEE J, MALCHOW R, MORROW F, SKOVPEN Y, SUNG M, WHITE C, WHITMORE J, WILSON P, BUTLER F, FU X, KALBFLEISCH G, LAMBRECHT M, ROSS WR, SKUBIC P, SNOW J, WANG PL, WOOD M, BORTOLETTO D, BROWN DN, FAST J, MCILWAIN RL, MIAO T, MILLER DH, MODESITT M, SCHAFFNER SF, SHIBATA EI, SHIPSEY IPJ, WANG PN, BATTLE M, ERNST J, KROHA H, ROBERTS S, SPARKS K, THORNDIKE EH, WANG CH, DOMINICK J, SANGHERA S, SHELKOV V, SKWARNICKI T, STROYNOWSKI R, VOLOBOUEV I, ZADOROZHNY P, ARTUSO M, HE D, GOLDBERG M, HORWITZ N, KENNETT R, MONETI GC, MUHEIM F, MUKHIN Y, PLAYFER S, ROZEN Y, STONE S, THULASIDAS M, VASSEUR G, ZHU G, BARTELT J, CSORNA SE, EGYED Z, JAIN V, SHELDON P, AKERIB DS, BARISH B, CHADHA M, CHAN S, COWEN DF, EIGEN G, MILLER JS, OGRADY C, URHEIM J, WEINSTEIN A
Slope failures along the deformation front of the Cascadia margin: linking slide morphology to subduction zone parameters
No full textMarine acoustic data are used to map and characterize submarine slope failure along the accretionary prism of Cascadia. Two main styles of slope failure are identified: (1) failures with curved head scarps, which are predominantly associated with incoherent debris-flow deposits; and (2) failures with rectangular head scarps, which are predominantly associated with intact sediment blocks. Rectangular head scarps mostly occur on thrust ridges with slope angles <16° and ridge heights <650 m, whereas curved head scarps occur predominantly on steeper and higher ridges. Off Vancouver Island, failure style and head-scarp geometry also change with ridge azimuth. We propose that the curved head scarps and debris flows may be a result of higher kinetic forcing of the downsliding sediments and a higher degree of mixing. At the more gently sloped, less elevated ridges, the kinetic forcing may be smaller, which leads to intact failure masses. Extensional faults at ridges with curved scarps may result from oversteepening and collapse of the sediments that cannot withstand their own weight due to limited internal shear strength. The slide geometries and potential controls on failure style may inform subsequent studies in assessing the risks for tsunami generation from submarine slope failures along the Cascadia margin
1982 2nd Year Natural Resource Management
No full textColor photo; unmounted.Second Year Nat Rats: back - J Sumner, G Saunders, D Appleton, L Sparrow, M Watson, M Stokes; centre - C MacDonald, I Hopton, A Comas, D Simpson, M Short, G Motson, S Holden, P Young; front - D Ganino, S Petho, L Hearde, K Ayliffe, L Miller, V Lintern, M Pearse
J. D. Brannan letter to Warren G. Harding, January 24, 1921
No full textIn this letter dated January 24, 1921 (the author mistakenly writes 1920), J. D. Brannan at Harvard University Law School to President-elect Warren G. Harding in regards to his choices for cabinet appointments. Brannan recommends Senator Elihu Root for Secretary of State, Charles Evans Hughes for Attorney General, Senator John W. Weeks for Secretary of the Treasury or Secretary of the Navy, and General Leonard Wood for Secretary of War, and includes qualifications for each. After discussing tensions among the government and organized labor leaders, he does not specify an appointment for Secretary of Labor, but includes Herbert Hoover as a qualified candidate.
This letter is part of the Warren G. Harding Papers (MSS 345). This collection includes correspondence, business records, and other materials documenting Harding’s business career as owner and editor-in-chief of The Daily Marion Star, as well as the various stages of his political career. A significant portion of the collection, and what’s available on Ohio Memory, highlights his 1920 presidential campaign, spanning just before publicly announcing his candidacy to handily defeating Ohio Governor James M. Cox in the election. Correspondents include both Ohio and national businessmen, political figures, and ordinary citizens writing with questions, support, congratulatory notes, and campaign advice. Some of the most interesting insights into the tumultuous political climate in the U.S., the extreme factionalism within the Republican Party in Ohio, and Harding’s campaign strategies are described in letters between Harding and his campaign manager, Harry M. Daugherty. Some of the topics addressed include women’s suffrage, Prohibition, the League of Nations, African American representation and issues, and lingering peace negotiations following World War I
Combining in situ monitoring using seabed instruments and numerical modelling to assess the transient stability of underwater slopes
No full textThe stability of submarine slopes is often characterized using campaign-based geophysical and geotechnical measurements in combination with numerical modelling. However, such one-off measurements do not reflect transient changes in slope stability. In situ monitoring of physical parameters critical for slope stability over periods of months to years can provide crucial information on slope stability and can also be used in an early-warning system for submarine landslides and the possibly resulting tsunamis. We review existing techniques that are capable of monitoring seafloor deformation over long periods of time. Based on numerical models we can identify the magnitude of parameters related to landslide-induced seafloor deformation. Simulations of three different failure scenarios up to the point of failure show that the development of the stress state of a slope and hence stability over time can be captured by measurements of tilt, pressure and strain at the seafloor. We also find that different failure mechanisms induce different deformation signals at the seafloor, in particular tilt. Hence, with a site- and target-specific survey design (or a large pool of instruments), seafloor deformation measurements in combination with numerical modelling can be used to determine the temporal evolution of slope stability as well as to identify underlying failure mechanisms
Geophysical and geochemical measurements on gravity cores along a transect down the Tuaheni Landslide Complex, northeastern New Zealand
No full textThe southern Tuaheni Landslide Complex (TLC) at the Hikurangi subduction margin displays distinctive morphological features along its distribution over the Tuaheni slope offshore Gisborne, New Zealand. The datasets provide geophysical (MSCL) and geochemical (XRF) core logs from a gravity core transect that systematically samples surficial sediments from the source area to the toe of this landslide complex
The deuteron spin-dependent structure function g(1)(d) and its first moment
No full textAlexakhin VY, Alexandrov Y, Alexeev GD, et al. The deuteron spin-dependent structure function g(1)(d) and its first moment. Phys.Lett. B. 2007;647(1):8-17.We present a measurement of the deuteron spin-dependent structure function g(1)(d) based on the data collected by the COMPASS experiment at CERN during the years 2002-2004. The data provide an accurate evaluation for Gamma(d)(1), the first moment of g(1)(d) (x), and for the matrix element of the singlet axial current, a(0). The results of QCD fits in the next to leading order (NLO) on all g(1) deep inelastic scattering data are also presented. They provide two solutions with the gluon spin distribution function Delta G positive or negative, which describe the data equally well. In both cases, at Q(2) = 3 (GeV/c)(2) the first moment of Delta G(x) is found to be of the order of 0.2-0.3 in absolute value. (c) 2007 Elsevier B.V. All rights reserved
Aspect-ratio dependence of the transition to the ultimate state of turbulent Rayleigh-Bénard convection
No full textWe report on measurements of the ultimate-state transition in turbulent Rayleigh-B\'enard convection obtained in a large facility known as the ``Uboot of G\"ottingen" and using pressurized sulfur hexafluoride as the convecting fluid. We found that the transition occurs over a range of which becomes more narrow as increases, ranging from which is at most weakly dependent on and close to to which varies from about for to about for
- …
