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Hydrothermal (NN)-N-15-N-15 abundances constrain the origins of mantle nitrogen 期刊论文
NATURE, 2020, 580 (7803) : 367-+
作者:  Zhao, Steven;  Jang, Cholsoon;  Liu, Joyce;  Uehara, Kahealani;  Gilbert, Michael;  Izzo, Luke;  Zeng, Xianfeng;  Trefely, Sophie;  Fernandez, Sully;  Carrer, Alessandro;  Miller, Katelyn D.;  Schug, Zachary T.;  Snyder, Nathaniel W.;  Gade, Terence P.;  Titchenell, Paul M.;  Rabinowitz, Joshua D.;  Wellen, Kathryn E.
收藏  |  浏览/下载：14/0  |  提交时间：2020/05/13

Nitrogen is the main constituent of the Earth'  s atmosphere, but its provenance in the Earth'  s mantle remains uncertain. The relative contribution of primordial nitrogen inherited during the Earth'  s accretion versus that subducted from the Earth'  s surface is unclear(1-6). Here we show that the mantle may have retained remnants of such primordial nitrogen. We use the rare (NN)-N-15-N-15 isotopologue of N-2 as a new tracer of air contamination in volcanic gas effusions. By constraining air contamination in gases from Iceland, Eifel (Germany) and Yellowstone (USA), we derive estimates of mantle delta N-15 (the fractional difference in N-15/N-14 from air), N-2/Ar-36 and N-2/He-3. Our results show that negative delta N-15 values observed in gases, previously regarded as indicating a mantle origin for nitrogen(7-10), in fact represent dominantly air-derived N-2 that experienced N-15/N-14 fractionation in hydrothermal systems. Using two-component mixing models to correct for this effect, the (NN)-N-15-N-15 data allow extrapolations that characterize mantle endmember delta N-15, N-2/Ar-36 and N-2/He-3 values. We show that the Eifel region has slightly increased delta N-15 and N-2/Ar-36 values relative to estimates for the convective mantle provided by mid-ocean-ridge basalts(11), consistent with subducted nitrogen being added to the mantle source. In contrast, we find that whereas the Yellowstone plume has delta N-15 values substantially greater than that of the convective mantle, resembling surface components(12-15), its N-2/Ar-36 and N-2/He-3 ratios are indistinguishable from those of the convective mantle. This observation raises the possibility that the plume hosts a primordial component. We provide a test of the subduction hypothesis with a two-box model, describing the evolution of mantle and surface nitrogen through geological time. We show that the effect of subduction on the deep nitrogen cycle may be less important than has been suggested by previous investigations. We propose instead that high mid-ocean-ridge basalt and plume delta N-15 values may both be dominantly primordial features.


  
Missing OH reactivity in the global marine boundary layer 期刊论文
ATMOSPHERIC CHEMISTRY AND PHYSICS, 2020, 20 (6) : 4013-4029
作者:  Thames, Alexander B.;  Brune, William H.;  Miller, David O.;  Allen, Hannah M.;  Apel, Eric C.;  Blake, Donald R.;  Bui, T. Paul;  Commane, Roisin;  Crounse, John D.;  Daube, Bruce C.;  Diskin, Glenn S.;  DiGangi, Joshua P.;  Elkins, JamesW.;  Hall, Samuel R.;  Hanisco, Thomas F.;  Hannun, Reem A.;  Hintsa, Eric;  Hornbrook, Rebecca S.;  Kim, Michelle J.;  McKain, Kathryn;  Moore, Fred L.;  Nicely, Julie M.;  Peischl, Jeffrey;  Ryerson, Thomas B.;  St Clair, Jason M.;  Sweeney, Colm;  Teng, Alex;  Thompson, Chelsea R.;  Ullmann, Kirk;  Wennberg, Paul O.;  Wolfe, Glenn M.
收藏  |  浏览/下载：14/0  |  提交时间：2020/07/02
Reorganization of surviving mammal communities after the end-Pleistocene megafaunal extinction 期刊论文
SCIENCE, 2019, 365 (6459) : 1305-+
作者:  Toth, Aniko B.;  Lyons, S. Kathleen;  Barr, W. Andrew;  Behrensmeyer, Anna K.;  Blois, Jessica L.;  Bobe, Rene;  Davis, Matt;  Du, Andrew;  Eronen, Jussi T.;  Faith, J. Tyler;  Fraser, Danielle;  Gotelli, Nicholas J.;  Graves, Gary R.;  Jukar, Advait M.;  Miller, Joshua H.;  Pineda-Munoz, Silvia;  Soul, Laura C.;  Villasenor, Amelia;  Alroy, John
收藏  |  浏览/下载：10/0  |  提交时间：2019/11/27
Global estimates of mortality associated with long-term exposure to outdoor fine particulate matter 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2018, 115 (38) : 9592-9597
作者:  Burnett, Richard;  Chen, Hong;  Szyszkowicz, Mieczyslaw;  Fann, Neal;  Hubbell, Bryan;  Pope, C. Arden;  Apte, Joshua S.;  Brauer, Michael;  Cohen, Aaron;  Weichenthal, Scott;  Coggins, Jay;  Di, Qian;  Brunekreef, Bert;  Frostad, Joseph;  Lim, Stephen S.;  Kan, Haidong;  Walker, Katherine D.;  Thurston, George D.;  Hayes, Richard B.;  Lim, Chris C.;  Turner, Michelle C.;  Jerrett, Michael;  Krewski, Daniel;  Gapstur, Susan M.;  Diver, W. Ryan;  Ostro, Bart;  Goldberg, Debbie;  Crouse, Daniel L.;  Martin, Randall V.;  Peters, Paul;  Pinault, Lauren;  Tjepkema, Michael;  van Donkelaar, Aaron;  Villeneuve, Paul J.;  Miller, Anthony B.;  Yin, Peng;  Zhou, Maigeng;  Wang, Lijun;  Janssen, Nicole A. H.;  Marra, Marten;  Atkinson, Richard W.;  Tsang, Hilda;  Thuan Quoc Thach;  Cannon, John B.;  Allen, Ryan T.;  Hart, Jaime E.;  Laden, Francine;  Cesaroni, Giulia;  Forastiere, Francesco;  Weinmayr, Gudrun;  Jaensch, Andrea;  Nagel, Gabriele;  Concin, Hans;  Spadaro, Joseph V.
收藏  |  浏览/下载：53/0  |  提交时间：2019/11/27
mortality  exposure  risk  concentration  fine particulate matter  
Carbon dioxide sources from Alaska driven by increasing early winter respiration from Arctic tundra 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2017, 114 (21) : 5361-5366
作者:  Commane, Roisin;  Lindaas, Jakob;  Benmergui, Joshua;  Luus, Kristina A.;  Chang, Rachel Y. -W.;  Daube, Bruce C.;  Euskirchen, Eugenie S.;  Henderson, John M.;  Karion, Anna;  Miller, John B.;  Miller, Scot M.;  Parazoo, Nicholas C.;  Randerson, James T.;  Sweeney, Colm;  Tans, Pieter;  Thoning, Kirk;  Veraverbeke, Sander;  Miller, Charles E.;  Wofsy, Steven C.
收藏  |  浏览/下载：7/0  |  提交时间：2019/11/27
carbon dioxide  Arctic  early winter respiration  Alaska  tundra  
Geomorphology of the Elwha River and its Delta: Chapter 3 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal 科技报告
来源：US Geological Survey (USGS). 出版年： 2011
作者:  Warrick, Jonathan A.;  Draut, Amy E.;  McHenry, Michael L.;  Miller, Ian M.;  Magirl, Christopher S. magirl@usgs.gov;  Beirne, Matthew M.;  Stevens, Andrew Stevens;  Logan, Joshua B.
收藏  |  浏览/下载：6/0  |  提交时间：2019/04/05