New Pepers 2013/12/15–2013/12/22 ELSEVIER

Geochimica et Cosmochimica Acta

1. Carbonation rates of peridotite in the Samail Ophiolite, Sultanate of Oman, constrained through 14C dating and stable isotopes
Author(s): Evelyn M. Mervine , Susan E. Humphris , Kenneth W.W. Sims , Peter B. Kelemen , William J. Jenkins

Palaeogeography, Palaeoclimatology, Palaeoecology

2. Late Quaternary productivity changes in the equatorial Indian Ocean (ODP Hole 716A)
Author(s): Sudipta Sarkar , Anil K. Gupta

Highlights
•Major productivity shift is recorded across the mid-Brunhes climatic transition (~ 300 Kyrs ago) at Hole 716A.
•Surface productivity and organic flux diminished after the mid-Brunhes transition at Hole 716A.
•Indian Ocean Equatorial Westerlies (IEW) played vital role in productivity shifts at Hole 716A.
•Shallow to intermediate and deep-sea environments were coupled during the late Quaternary at Hole 716A.
•Faunal population remains least affected across glacial-interglacial transitions.

Keywords
Hole 716A; late Quaternary; mid-Brunhes; equatorial Indian Ocean; foraminifera; paleoenvironment; Indian Ocean equatorial westerlies (IEW)

3. Palynofacies and stable C and N isotopes of Holocene sediments from Lake Macuco (Linhares, Espírito Santo, southeastern Brazil): Depositional settings and palaeonvironmental evolution
Author(s): Flávio Lima Lorente , Luiz Carlos Ruiz Pessenda , Francisca Oboh-Ikuenobe , Antonio Alvaro Buso Jr. , Marcelo Cancela Lisboa Cohen , Karin Elise Bohns Meyer , Paulo César Fonseca Giannini , Paulo Eduardo de Oliveira , Dilce de Fátima Rossetti , Marcos Antonio Borotti Filho , Marlon Carlos França , Darciléa Ferreira de Castro , José Albertino Bendassolli , Kita Macario

Highlights
•A lake in southeastern Brazilian coast was studied by palynofacies, δ13C, δ15N and C/N
•An estuarine system occurred between 7,5 and 3,8 k cal yr. B.P.
•Over the past 3,8 k cal yr. B.P. a lake was developed
•Transgressive and regressive events occurred in the study site during the Holocene.

Keywords
Holocene; organic matter; palynofacies; carbon and nitrogen isotopes; southeastern Brazil

4. Stable isotopes on foraminifera and ostracods for interpreting incidence of the Toarcian Oceanic Anoxic Event in Westernmost Tethys: Role of water stagnation and productivity
Author(s): Matías Reolid

Highlights
•δ13C and δ18O from bulk rock and shells of foraminifera and ostracods from T-OAE.
•δ13C values are lower in Lenticulina indicating more depleted 13C in sediment pore-water of deep infaunal microhabitat.
•Lowest δ13C, diversity and abundance of foraminifera and higher TOC occur during suboxic conditions.
•δ13C of deep infauna reflect the suboxic conditions better than shallow infauna and whole sediment.
•Differences between δ18O of Dentalina and Lenticulina shells correspond to vital effect.

Keywords
Lagenina; vital effect; microhabitat effect; isotopic excursion; redox conditions; Lower Jurassic

5. Paleoclimatic changes on the southern Tibetan Plateau over the past 19,000years recorded in Lake Pumoyum Co, and their implications for the southwest monsoon evolution
Author(s): Mitsugu Nishimura , Tetsuya Matsunaka , Yoshimune Morita , Takahiro Watanabe , Toshio Nakamura , Liping Zhu , Fumiko Watanabe Nara , Akio Imai , Yasuhiro Izutsu , Kazuya Hasuike

Highlights
•We reconstructed the paleoclimate in the southern Tibetan Plateau (STP) since 19 ka.
•The paleoclimate was ameliorated earliest within the SW monsoon domain on the TP.
•The STP experienced almost no impact from all major dry/cold reversals.
•The first SW monsoon on the TP after the Y.D. generated at 11.4 ka BP in the STP.
•Subsequently, the monsoon extended from STP over the entire TP taking 3-4 kyrs.
Keywords
Southern Tibetan Plateau; Lake Sediments; Multi-proxy Analysis; Paleoclimatic Changes; Southwest Monsoon

6. Adélie Penguin dietary remains reveal Holocene environmental changes in the western Ross Sea (Antarctica)
Author(s): Sandra Lorenzini , Carlo Baroni , Ilaria Baneschi , Maria Cristina Salvatore , Anthony E. Fallick , Brenda L. Hall

Highlights
•The C and N isotopic composition of Adélie penguin guano samples has been investigated.
•Dietary remains have been found in sorted guano samples and taxonomically identified.
•A detailed paledietary record has been reconstructed for the southern Ross Sea.
•New insights into the Holocene oceanographic conditions of Ross Sea are discussed.
Keywords
Adélie Penguin; ornithogenic soil; stable isotope; palaeoenvironment; palaeoceanography

7. Geochemical records of palaeoenvironmental controls on peat forming processes in the Mfabeni peatland, Kwazulu Natal, South Africa since the Late Pleistocene
Author(s): A. Baker , J. Routh , M. Blaauw , A.N. Roychoudhury

Highlights
•Mfabeni peatland oldest land based climate record in southern Africa
•5 linear sedimentation rate stages indicating changes in hydraulic conditions
•High resolution hydraulic and plant assemblage record and their climatic controls
•Archive suggests an anti-phase climatic link with the northern hemisphere

Keywords
Palaeoenvironment; Palaeoclimate; Subtropical coastal peatland; Stable C and N isotopes; Elemental analyses

8. Nitrogen and organic carbon isotope stratigraphy of the Yangtze Platform during the Ediacaran-Cambrian transition in South China
Author(s): Lorenzo Cremonese , Graham A. Shields-Zhou , Ulrich Struck , Hong-Fei Ling , Lawrence M. Och

Highlights
•N and Corg analyses indicate an articulated and periodically complete nitrogen cycle.
•Nitrogen isotopes are potent geochemical tools to monitor the oxidative conditions of the seawater.
•We are able to build a paleoseawater circulation system across the Pc-C boundary.
•Episodically occurrence of green/purple sulfur Bacteria has been envisaged.
•Nitrogen isotopes preserved in rock sediments retained their original values.

Keywords
Ediacaran; Cambrian; nitrogen isotopes; organic carbon isotopes; Yangtze platform; marine biogeochemistry
9. Ecological effects of natural hazards and human activities on the Ecuadorian Pacific coast during the Late Holocene
Author(s): Sophak Lim , Marie-Pierre Ledru , Francisco Valdez , Benoît Devillers , Alfred Hougnon , Charly Favier , Laurent Bremond
Highlights
•A sediment core on coastal eastern Pacific dates back to 5000 cal yr BP
•XRF, stereomicroscopic, charcoal and pollen contents were analyzed.
•At ~ 3000 yr BP an earthquake induced changes in fluvial and geomorphological features.
•Increase of human activities was observed between 2980 and 1170 cal yr BP
•Climate conditions have not changed in the Choco region during the past 5000 years

Keywords
Pacific coast; rainforest; Ecuador; Choco biogeographic region; pollen; Holocene

Quaternary Research

10. Geochronology and paleoenvironment of pluvial Harper Lake, Mojave Desert, California, USA
Author(s): Anna L. Garcia , Jeffrey R. Knott , Shannon A. Mahan , Jordon Bright

Keywords
Mojave River; Harper Lake; Paleoclimate; Polar jet stream; Ostracode; Lake Manix; Geochronology; Radiocarbon; OSL; IRSL

Quaternary Science Reviews

11. Insights into continental temperatures in the northwestern Black Sea area during the Last Glacial period using branched tetraether lipids
Author(s): Lise Sanchi , Guillemette Ménot , Edouard Bard

Highlights
•We used branched GDGTs to infer Last Glacial temperatures in Black Sea catchment.
•We propose temperature corrections regarding possible branched GDGT origins.
•Cold spells related to the Younger Dryas, LGM and HE 2–3 are detected.
•Dansgaard–Oeschger interstadials 2–8 are not imprinted in the signals.

Keywords
brGDGTs; Black Sea; Continental paleotemperatures; MBT/CBT; Last Glacial; Abrupt climate changes

12. Arctic Ocean perennial sea ice breakdown during the Early Holocene Insolation Maximum
Author(s): Christian Stranne , Martin Jakobsson , Göran Björk

Keywords
Arctic climate; Holocene; Milankovitch cycles; Bølling–Allerød; Albedo feedback; Arctic sea ice

Chemical Geology
Earth and Planetary Science Letters
Palaeogeography, Palaeoclimatology, Palaeoecology
Global and Planetary Change
Marine Geology
Quaternary Geochronology
Quaternary International
Nothing Relevant

新着論文紹介 This Week’s New Paper (2013/12/24) AGU, etc…

♪G-cubed♪

1. Comparable hydrogen isotopic fractionation of plant leaf wax n-alkanoic acids in arid and humid subtropical ecosystems

G-cubed by Li Gao, Mei Zheng, Matthew Fraser, Yongsong Huang

DOI: 10.1002/2013GC005015

♪GRL♪

2. Interactions between externally-forced climate signals from sunspot peaks and the internally-generated Pacific Decadal and North Atlantic Oscillations

Harry Loon, Gerald A. Meehl

DOI: 10.1002/2013GL058670

3. Is climate sensitivity related to dynamical sensitivity? A Southern Hemisphere perspective

Kevin M. Grise, Lorenzo M. Polvani

DOI: 10.1002/2013GL058466

4. Response of atmospheric CO2 to the abrupt cooling event 8200 years ago

Jinho Ahn, Edward J. Brook, Christo Buizert

DOI: 10.1002/2013GL058177

♪JGR-Oceans♪

5. Polynya dynamics drive primary production in the Larsen A and B embayments following ice shelf collapse

Mattias R. Cape, Maria Vernet, Mati Kahru, Gunnar Spreen

DOI: 10.1002/2013JC009441

6. A closer look at the Central Pacific El Niño and warm pool migration events from 1982-2011

Autumn Kidwell, Young-Heon Jo, Xiao-Hai Yan

DOI: 10.1002/2013JC009083

♪Paleoceanography♪

7. Middle Eocene to Late Oligocene Antarctic Glaciation/Deglaciation and Southern Ocean productivity

Giuliana Villa, Chiara Fioroni, Davide Persico, Andrew P. Roberts, Fabio Florindo

DOI: 10.1002/2013PA002518

8. Consequences of shoaling of the Central American Seaway determined from modelling Nd isotopes

P. Sepulchre, T. Arsouze, Y. Donnadieu, J.-C. Dutay, C. Jaramillo, J. Le Bras, E. Martin, C. Montes, A. J. Waite

DOI: 10.1002/2013PA002501

GBC, GSA Bulletin, Climate of the past新着なし

JOURNAL REVIEW December 16 – December 23 (Nature, Science, PNAS, Nature Geoscience, Nature Communications)

NATURE

1. China lands rover on Moon

David Cyranoski

China has become only the third country to soft-land a craft on the Moon— and the first to do so since the Soviet Union in 1976. Its Chang’e 3 spacecraft dropped safely to the surface on 14 December.

2. Seabed scars raise questions over carbon-storage plan

Richard Monastersky

Unexpected fractures above the world’s biggest storage site could provide path for leaks.

3. Worldwide acceleration of mountain erosion under a cooling climate

Frédéric Herman, Diane Seward, Pierre G. Valla,  Andrew Carter, Barry Kohn, Sean D. Willett & Todd A. Ehlers

Nature 504, 423–426 (19 December 2013) doi:10.1038/nature12877

To establish what effect the Late Cenozoic cooling climate shift might have had on global erosion, inverse modelling of thermochronometric ages is used to show that erosion rates are increased by cooling, especially in glaciated mountain ranges.

SCIENCE

4. Sea-Level Rise by 2100

John A. Church, Peter U. Clark, Anny Cazenave, Jonathan M. Gregory, Svetlana Jevrejeva, Anders Levermann, Mark A. Merrifield, Glenn A. Milne, R. Steven Nerem, Patrick D. Nunn, Antony J. Payne, W. Tad Pfeffer, Detlef Stammer, and Alakkat S. Unnikrishnan

Science 20 December 2013: Vol. 342 no. 6165 pp. 1445, DOI:10.1126/science.342.6165.1445-a

5. Unexpected Stable Stoichiometries of Sodium Chlorides

Weiwei Zhang, Artem R. Oganov, Alexander F. Goncharov, Qiang Zhu, Salah Eddine Boulfelfel, Andriy O. Lyakhov, Elissaios Stavrou, Maddury Somayazulu, Vitali B. Prakapenka, and Zuzana Konôpková

Science 20 December 2013: 1502-1505.

We synthesized cubic and orthorhombic NaCl₃ and two-dimensional metallic tetragonal Na₃Cl. These experiments establish that compounds violating chemical intuition can be thermodynamically stable even in simple systems at nonambient conditions.

Our results suggest that new stable compositions with unusual chemical bonding may exist in other simple systems, such as important planet-forming systems such as Mg-Si-O and H-C-N-O.

PNAS

6. Formation of highly porous aerosol particles by atmospheric freeze-drying in ice clouds

Gabriela Adler, Thomas Koop, Carynelisa Haspel, Ilya Taraniuk, Tamar Moise, Ilan Koren, Reuven H. Heiblum, and Yinon Rudich

PNAS 2013 110 (51) 20414-20419; published ahead of print December 2, 2013, doi:10.1073/pnas.1317209110

Here we simulate an atmospheric freeze-drying cycle of aerosols in laboratory experiments using proxies for atmospheric aerosols. We find that aerosols that contain organic material that undergo such a process can form highly porous aerosol particles with a larger diameter and a lower density than the initial homogeneous aerosol. These observations may have implications for subsequent cloud formation cycles and aerosol albedo near cloud edges.

7. Sensitivity to ocean acidification parallels natural pCO2 gradients experienced by Arctic copepods under winter sea ice

Ceri N. Lewis, Kristina A. Brown, Laura A. Edwards, Glenn Cooper, and Helen S. Findlay

PNAS 2013 110 (51) E4960-E4967; published ahead of print December 2, 2013, doi:10.1073/pnas.1315162110

Here, we report results from Arctic under-ice investigations of copepod natural distributions associated with late-winter carbonate chemistry environmental data and their response to manipulated pCO2 conditions (ocean acidification (OA) exposures). The results support the hypothesis that the natural range of pCO2 experienced by an organism determines its sensitivity to future OA

NATURE GEOSCIENCE

8. Delamination and recycling of Archaean crust caused by gravitational instabilities

Tim E. Johnson, Michael Brown, Boris J. P. Kaus & Jill A. VanTongeren

Nature Geoscience 7, 47–52 (2014) doi:10.1038/ngeo2019

The Archaean Earth was much hotter than today. Numerical modelling shows that the base of thickened crust that formed at the time would have been so dense that it dripped back into the mantle.

9. Ebullition and storm-induced methane release from the East Siberian Arctic Shelf

Natalia Shakhova, Igor Semiletov, Ira Leifer, Valentin Sergienko, Anatoly Salyuk, Denis Kosmach, Denis Chernykh, Chris Stubbs, Dmitry Nicolsky, Vladimir Tumskoy & Örjan Gustafsson

Nature Geoscience 7, 64–70 (2014) doi:10.1038/ngeo2007

Large quantities of methane lie trapped beneath the floor of the Arctic Ocean. Measurements in the southern Laptev Sea around the Lena River delta suggest that bubbles and storms facilitate the flux of some of this submarine methane to the atmosphere.

10. Ocean-driven heating of Europa’s icy shell at low latitudes

K. M. Soderlund, B. E. Schmidt, J. Wicht & D. D. Blankenship

Nature Geoscience 7, 16–19 (2014) doi:10.1038/ngeo2021

Liquid water may hide beneath the frozen surfaces of Jupiter's moon Europa and other icy worlds. Extending ocean science beyond Earth, planetary oceanographers are linking Europa's ocean dynamics to its enigmatic surface geology.

11. Potential influence of sulphur bacteria on Palaeoproterozoic phosphogenesis

Aivo Lepland, Lauri Joosu, Kalle Kirsimäe, Anthony R. Prave, Alexander E. Romashkin, Alenka E. Črne, Adam P. Martin, Anthony E. Fallick, Peeter Somelar, Kärt Üpraus, Kaarel Mänd, Nick M. W. Roberts, Mark A. van Zuilen, Richard Wirth & Anja Schreiber

Nature Geoscience 7, 20–24 (2014) doi:10.1038/ngeo2005

The first known phosphorus-rich deposits formed 2 billion years ago, but their origins are unclear. Geochemical and palaeontological analyses of 2-billion-year-old deposits from northwest Russia suggest that the presence of sulphur-oxidizing bacteria and a sharp oxic–anoxic transition in the sediments allowed for phosphorus accumulation in this setting.

12. Evidence for biogenic graphite in early Archaean Isua metasedimentary rocks

Yoko Ohtomo, Takeshi Kakegawa, Akizumi Ishida, Toshiro Nagase & Minik T. Rosing

Nature Geoscience 7, 25–28 (2014) doi:10.1038/ngeo2025

The Archaean rocks of Isua, West Greenland, contain graphite, but its origins are debated. Geochemical and microscopic analyses suggest that the graphite was formed from biologically formed carbon that was deposited at least 3.7 billion years ago.

13. Recurring slope lineae in equatorial regions of Mars

Alfred S. McEwen, Colin M. Dundas, Sarah S. Mattson, Anthony D. Toigo, Lujendra Ojha, James J. Wray, Matthew Chojnacki, Shane Byrne, Scott L. Murchie & Nicolas Thomas

Nature Geoscience 7, 53–58 (2014) doi:10.1038/ngeo2014

Dark streaks that appear on the surface of Mars during warm seasons have been observed at the mid-latitudes and tentatively attributed to the flow of briny water. Imagery from the Mars Reconnaissance Orbiter over multiple Mars years suggests that these seasonally active features are also present in equatorial regions, where liquid surface water is not expected.

14. Warming early Mars with CO₂ and H₂

Ramses M. Ramirez, Ravi Kopparapu, Michael E. Zugger, Tyler D. Robinson, Richard Freedman & James F. Kasting

Nature Geoscience 7, 59–63 (2014) doi:10.1038/ngeo2000

Ancient valleys suggest a warm early Mars where liquid water flowed, but a greenhouse effect strong enough to offset a dim early Sun has been difficult to explain. Climate simulations suggest that sufficient concentrations of the greenhouse gases CO₂ and H₂ — outgassed during volcanic eruptions — could have warmed Mars above water’s freezing point.

NATURE COMMUNICATIONS

15. Spatial optimization of carbon-stocking projects across Africa integrating stocking potential with co-benefits and feasibility

Michelle Greve, Belinda Reyers, Anne Mette Lykke & Jens-Christian Svenning

Nature Communications 4, Article number: 2975 doi:10.1038/ncomms3975

Received 28 June 2013 Accepted 21 November 2013 Published 19 December 2013

Africa is one of the fastest growing regions for the voluntary carbon market. Here, Greve et al. quantify the potential for aboveground C stocking across tropical Africa and assess the optimal placement of carbon-stocking projects when also taking co-benefits and feasibility into account. 

16. The discovery of kimberlites in Antarctica extends the vast Gondwanan Cretaceous province

Gregory M. Yaxley, Vadim S. Kamenetsky, Geoffrey T. Nichols, Roland Maas, Elena Belousova, Anja Rosenthal & Marc Norman

Nature Communications 4, Article number: 2921 doi:10.1038/ncomms3921

Received 09 September 2013 Accepted 12 November 2013 Published 17 December 2013

Here we report the first bona fide Antarctic kimberlite occurrence, from the northern Prince Charles Mountains, emplaced during rifting of India from Australia-Antarctica.

Journal Review 11 – 17 Dec (Nature, Science, Geology, PNAS, Nature Communications)

NATURE

1. Melting ice spurs wild weather

Nature 504, 190 (12 December 2013) doi: 10.1038/504190c

Nature Clim. Change http://doi.org/qds (2013)

Arctic sea-ice retreat and, to a lesser degree, decreased snow cover were found to alter large-scale atmospheric circulation patterns. These typically cause heatwaves and other extreme weather events at mid-latitudes.

2. Life possible in the early Universe

Zeeya Merali

Nature 504, 201 (12 December 2013) doi: 10.1038/504201a

The energy required to keep water liquid in the early Universe could have come from the cosmic microwave background, the afterglow of the Big Bang, rather than from host stars. A habitable epoch of 2 to 3 million years was proposed, during which all rocky planets would have been able to maintain liquid water regardless of their distance from a star.

3. Gas production contaminates water

Nature 504, 191 (12 December 2013) doi: 10.1038/504191f

Environ. Sci. Technol. 47, 11849-11857 (2013)

Wastewater from oil and gas production has been shown to cause an increase in contaminants, such as chloride and radium, in surface waters and sediments in Western Pennsylvania.

4. Food fuelled with fungi

Nicola Jones

Nature 504, 199 (12 December 2013) doi: 10.1038/504199a

Researchers have harnessed the symbiotic relationship endophytes have with plants to improve crop yield and reduce water use.

SCIENCE

5. New results send Mars rover on a quest for ancient life

Richard A. Kerr

Vol. 342 no. 6164 pp. 1300-1301 doi: 10.1126/science.342.6164.1300

Lakebed samples from Mars may indicate organic carbon content. The Curiosity rover has also determined how recently surface rocks have been exposed by erosion, opening the way to more systematic searches for molecular fossils by showing scientists how to maximise chances of finding organic matter that has only recently been exposed to cosmic rays.

6. Europe readies peerless star mapper

Daniel Clery

Vol. 342 no. 6164 p. 1305 doi: 10.1126/science.342.6164.1305

Gaia will map the positions and motions of stars in the Milky Way with 200 times the accuracy of Hipparcos, its predecessor in the early 1990s.

GEOLOGY

7. Riverine mixing and fluvial iron formation: A new type of Precambrian biochemical sediment

Peir K. Pufahl, Franco Pirajno & Eric. E. Hiatt

Vol. 41 no. 12 p. 1235-1238 doi: 10.1130/G34812.1

Fluvial iron formation is a new type of Fe-rich microbial-biochemical sediment that formed by mixing river discharge and seawater in coastal environments. Because these precipitated at the interface between terrestrial and marine realms instead of typically marine settings, they may allow further research into ocean-atmosphere evolution.

8. Subduction and deformation of the continental lithosphere in response to plate and crust-mantle coupling

E. Willingshofer, D. Sokoutis, S. W. Luth, F. Beekman & S. Cloetingh

Vol. 41 no. 12 p. 1239-1242 doi: 10.1130/G34815.1

Experimental results show subduction of slabs is deepest in cases with strong decoupling at the plate interface and at the level of the lower crust of the downgoing plate, with upper-plate deformation restricted to the area close to the plate contact. The degree of plate coupling determines the efficiency of subduction of continental lithosphere under conditions of collision of neutrally buoyant lithospheres. The results explain the geometry and sequence of deformation in subduction-dominated orogens, such as the Carpathians or the Dinarides.

9. Glacier slip and seismicity induced by surface melt

Peter L. Moore, J. Paul Winberry, Neal R. Iverson, Knut A. Christianson, Sridhar Anandakrishnan, Miriam Jackson, Mark E. Mathison & Denis Cohen

Vol. 41 no. 12 p. 1247-1250 doi: 10.1130/G34760.1

Direct measurements of basal hydrology, sliding and broadband seismicity were obtained in a unique subglacial facility in Norway. In the most pronounced episode, rapid delivery of surface meltwater to the bed briefly enhanced basal slip following a period of elevated high-frequency seismic activity related to surface crevassing. The results support theoretical models for hydraulic jacking and illustrate how melt-induced increases in speed can be short-lived if cavity growth or ice-bed decoupling allows basal water more efficient drainage.

NATURE COMMUNICATIONS

10. Increases in terrestrially derived carbon stimulate organic carbon processing and CO₂ emissions in boreal aquatic ecosystems

Jean-Francois Lapierre, Francois Guillemette, Martin Berggren & Paul A. del Giorgio

Nature Communications 4, 2972 (2013) doi: 10.1038/ncomms3972

Via the analysis of hundreds of boreal lakes, rivers and wetlands in Canada, the proportion of biologically degradable dissolved organic carbon was shown to remain constant and the photochemical degradability to increase with terrestrial influence. There is thus a strong causal link between dissolved organic carbon concentrations and aquatic fluxes of carbon dioxide, mediated by the degradation of land-derived organic carbon in aquatic ecosystems.