Geochemistry articles within Nature Communications

Featured

• Article | 28 May 2013

  Inferred time- and temperature-dependent cation ordering in natural titanomagnetites

  Cation ordering in cubic-structured oxides can strongly affect magnetic properties. Here, the authors show that in some natural titanomagnetites, large and reversible changes in Curie temperature result from annealing at moderate temperatures (350–400 °C), most likely arising from changes in cation ordering.

  • Julie A. Bowles
  • , Mike J. Jackson
  •  & Jeffrey S. Gee

• Article | 30 April 2013

  Pyroclastic passage zones in glaciovolcanic sequences

  Subglacial volcanoes host passage zones that can be used to define high stands of englacial lakes and paleo-ice thickness. This study identifies a pyroclastic passage zone in a subglacial volcano, which may help calculate transient paleolake levels and improve estimates of paleo-ice thickness.

  • James K. Russell
  • , Benjamin R. Edwards
  •  & Lucy A. Porritt

• Article | 23 April 2013

  Discovery of seifertite in a shocked lunar meteorite

  Few high-pressure polymorphs have been found from lunar meteorites even though the moon has experienced heavy meteorite bombardment. This study presents evidence of a high-pressure polymorph of silica—seifertite—from a lunar meteorite; a record of an intense planetary collision on the moon ~2.7 Ga ago.

  • Masaaki Miyahara
  • , Shohei Kaneko
  •  & Naohisa Hirao

• Article | 09 April 2013

  Early Cretaceous chalks from the North Sea giving evidence for global change

  Calcareous nannofossils were important marine primary producers in Jurassic and Cretaceous oceans at low latitudes. Here, North Sea sediment records reveal that favourable conditions for nannoconids existed also at high latitudes, and nannoconids faced global decline at the onset of greenhouse conditions.

  • Jörg Mutterlose
  •  & Cinzia Bottini

• Article | 05 February 2013

  Effect of iron oxidation state on the electrical conductivity of the Earth’s lower mantle

  In the Earth’s lower mantle, pressure changes can cause spin transitions of iron, in turn influencing mantle properties. Here a new Mössbauer spectroscopy method is applied to show that Fe³⁺remains in the high-spin state at pressure–temperature conditions relevant for the lower mantle.

  • V. Potapkin
  • , C. McCammon
  •  & L. Dubrovinsky

• Article | 16 October 2012

  A four-dimensional X-ray tomographic microscopy study of bubble growth in basaltic foam

  Changes in bubble foam structure influence magma strength. Here, Bakeret al. measure bubble size and wall thickness of basaltic foams and find that basaltic magmas are most likely to fail immediately upon vesiculation, but a permeability increase within a few seconds may reduce the risk of explosive eruptions.

  • Don R. Baker
  • , Francesco Brun
  •  & Mark Rivers

• Article
  10 January 2012 | Open Access

  Hydrothermal vent fields and chemosynthetic biota on the world's deepest seafloor spreading centre

  The Mid-Cayman Spreading Centre is an ultraslow-spreading mid-ocean ridge in the Caribbean. This study reveals two hydrothermal vent fields on the ridge, including high-temperature vents on an off-axis oceanic core complex where, similar to Mid-Atlantic vents, an alvinocaridid shrimp is common at both vent fields.

  • Douglas P. Connelly
  • , Jonathan T. Copley
  •  & Sally Wilcox