Solid Earth sciences

  • Article
    | Open Access

    Visualization of magma in a conduit with classical probes remains challenging due to geological heterogeneity and the geometrical structure of the conduit involved. Tanaka et al.use cosmic ray muons and report the first radiographic observation of the ascent and descent of magma along a conduit.

    • Hiroyuki K. M. Tanaka
    • , Taro Kusagaya
    •  & Hiroshi Shinohara
  • Article |

    Sedimentary rocks record planetary environmental history convolved with the internal dynamics of depositional landscapes. Ganti et al.show that the advection length of settling sediment sets bounds on internal landscape dynamics, providing a new tool to unravel sedimentary archives.

    • Vamsi Ganti
    • , Michael P. Lamb
    •  & Brandon McElroy
  • Article
    | Open Access

    Ocean acidification is affecting the stability of coral reefs, but the exact mineralogical response is poorly understood. Diaz-Pulido et al.show that, under warming conditions, the relative abundance of dolomite increases by as much as 200% and could therefore slow the climate-induced break-up of coral reefs.

    • Guillermo Diaz-Pulido
    • , Merinda C. Nash
    •  & Ulrike Troitzsch
  • Article
    | Open Access

    Understanding dyke thickness distributions is essential to quantify magma transport rates and improve eruption forecasting. Krumbholz et al.show that dyke thicknesses are Weibull-distributed and identify host-rock strength as the primary parameter that controls dyke emplacement.

    • Michael Krumbholz
    • , Christoph F. Hieronymus
    •  & Nadine Friese
  • Article |

    Humans have influenced the shaping of the landscape for generations, yet disentangling these influences from those of climate is a challenge. Giguet-Covex et al.take the novel approach of using lake sediment DNA to reconstruct a detailed picture of human land use since the Neolithic Period.

    • Charline Giguet-Covex
    • , Johan Pansu
    •  & Pierre Taberlet
  • Article |

    Kimberlite, an igneous rock in which the majority of the world’s diamonds are found, has been reported on all major continents barring Antarctica. Yaxley et al. present mineralogical and chemical data that confirms the first bona fidediscovery of kimberlite in the Antarctic.

    • Gregory M. Yaxley
    • , Vadim S. Kamenetsky
    •  & Marc Norman
  • Article |

    Obsidian lava flows accompanied some of Earth’s most powerful eruptions, yet an active advancing flow field has never been observed. Tuffen et al.present four-dimensional models of the lava flow following the 2011 eruption of Cordón Caulle, Chile, and provide new insights into silicic lava flow dynamics.

    • Hugh Tuffen
    • , Mike R. James
    •  & C. Ian Schipper
  • Article |

    The El Niño-Southern Oscillation is one of the largest sources of global climate variability, yet our understanding relative to the Topical Pacific mean state is poor. Here, geochemical analyses of marine plankton reveal a strong link between zonal sea-surface temperatures and ENSO variability.

    • Aleksey Yu Sadekov
    • , Raja Ganeshram
    •  & Alexander W. Tudhope
  • Article |

    With the exception of one occurrence, carbonatites worldwide are curiously deficient in alkalis. Here, Chen et al.present new melt inclusion data from plutonic relics in Canada that hint at a wider prevalence of alkali-enriched parental carbonatite in the geological record than previously thought.

    • Wei Chen
    • , Vadim S. Kamenetsky
    •  & Antonio Simonetti
  • Article
    | Open Access

    The mechanism by which Mars lost its early dense and carbon dioxide-rich atmosphere remains relatively unknown. Here, via mineralogical analysis of the Lafayette Martian meteorite, Tomkinson et al. infer that carbonation was an effective carbon dioxide sequestration mechanism on an early, water-rich Mars.

    • Tim Tomkinson
    • , Martin R. Lee
    •  & Caroline L. Smith
  • Article
    | Open Access

    Before the mass extinction that characterized the Late Triassic period, there were a series of biotic turnover events, the cause of which are the subject of debate. Sato et al. present geochemical evidence in support of the theory that extraterrestrial impacts had an important role in these events.

    • Honami Sato
    • , Tetsuji Onoue
    •  & Katsuhiko Suzuki
  • Article |

    Sedimentation along convergent plate margins, the destructive sites of tectonic plate collision, is poorly understood. Malatestaet al.use a cutting-edge three-dimensional subduction model to demonstrate that the trench-parallel motion of sediments has a much more important role than previously thought.

    • Cristina Malatesta
    • , Taras Gerya
    •  & Giovanni Capponi
  • Article
    | Open Access

    The astronomical time scale is an essential geochronological tool, but is presently limited to the Cenozoic and Mesozoic eras. Here, Wuet al.time-calibrate Milankovitch cycles identified in strata from South China and extend this essential tool into the late Permian.

    • Huaichun Wu
    • , Shihong Zhang
    •  & Tianshui Yang
  • Article |

    Alaskan mountain glaciers are losing ice and contribute to sea level rise, but contributions from specific ice-loss mechanisms are not known. Here, calving losses in Central Alaska are found to equal 36% of the net regional mass change each year and regional flux is dictated largely by snow accumulation rates.

    • Evan W. Burgess
    • , Richard R. Forster
    •  & Christopher F. Larsen
  • Article
    | Open Access

    Low-resistivity crustal fluids occur near fault zones, but their relation to earthquake generation is unclear. Here, electromagnetic data from the Izmit earthquake reflects the pressure-induced transition between isolated and interconnected fluids that is linked to foreshocks before large earthquakes.

    • Yoshimori Honkura
    • , Naoto Oshiman
    •  & Elif Tolak Çiftçi
  • Article |

    Debates on the formation of banded iron formations (BIFs) in ancient iron-rich oceans are dominated by contradictions between biological and non-biological iron cycling. This study provides environmental evidence that directly implicates photosynthetic iron-oxidizing microorganisms in vast-scale BIF deposition.

    • Ernest Chi Fru
    • , Magnus Ivarsson
    •  & Marco Stampanoni
  • Article |

    The evolution of continental rifting curvature can be studied using thermal convection models. Studying how this curvature controls the subsidence of offshore basins, Sacek and Ussami find that the mantle viscosity structure affects the subsidence rate and evolution of sedimentary basins along curved margins.

    • Victor Sacek
    •  & Naomi Ussami
  • Article |

    The North Anatolian Fault Zone in Turkey has produced many large earthquakes, however the Marmara region has been inactive and is facing a high probability for a large earthquake. Here, Bohnhoff et al. report on a large seismicity gap in this area with implications for a seismic hazard for Istanbul.

    • Marco Bohnhoff
    • , Fatih Bulut
    •  & Mustafa Aktar
  • Article |

    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 |

    In the Late Triassic, southern Gondwanan flora is thought to have been dominated by endemic species mainly restricted to eastern areas with some mixing with northern species. In this study, pollen and spore assemblages from Argentina reveal the presence of these mixed flora in the westernmost Gondwana as well.

    • Silvia N Césari
    •  & Carina E Colombi
  • Article |

    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 |

    The role of bacteria in the origin of iron formations (IF) remains unclear because no direct evidence for their involvement exists. This study shows that spherical siderite in deep-water IF represents a biosignature for photoferrotrophy, whereas massive siderite reflects high cyanobacterial biomass in shallow-water.

    • Inga Köhler
    • , Kurt O Konhauser
    •  & Andreas Kappler
  • Article |

    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 |

    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 |

    The onset of the ongoing summit eruption at Kilauea Volcano was associated with changes in seismic anisotropy and increased gas flux. This study shows that seismic anisotropy variations are also a function of alterations in stress conditions, and provides a new method for tracking gas flux using seismic observations.

    • Jessica H. Johnson
    •  & Michael P. Poland
  • Article |

    Clear evidence between sulphidic conditions and denitrification in the Proterozoic ocean should be observable in the rock record. Here, minimalistic biogeochemical modelling shows how periods of extensive sulphate reduction must have gone hand-in-hand with low denitrification and available nitrate.

    • R.A. Boyle
    • , J.R. Clark
    •  & T.M. Lenton
  • Article |

    In mature continental rifts, magma intrusion appears to accommodate significant crustal extension. Here, radiometric ages for lavas suggest that this style of focused magmatic accretion and rifting remained stable in the Ethiopian crust for at least ~200 kyr, prior to the onset of true oceanic spreading.

    • David J. Ferguson
    • , Andrew T. Calvert
    •  & Tim J. Wright
  • Article |

    High-pressure minerals in meteorites reflect the conditions prevailing when they were excavated and launched from their parent bodies. Tissint—a recent Martian meteorite—contains an unusual number of large high-pressure minerals, suggesting excavation from an impact of larger magnitude than for previous Martian samples.

    • Ioannis P. Baziotis
    • , Yang Liu
    •  & Lawrence A. Taylor
  • Article
    | Open Access

    Active seafloor spreading has been documented in some of the tectonically active basins of the Gulf of California. This work presents new geophysical and geochemical data as evidence that active seafloor spreading is also occurring in the northernmost Wagner and Consag basins of the Gulf.

    • Rosa Ma Prol-Ledesma
    • , Marco-Antonio Torres-Vera
    •  & Carlos Robinson
  • Article |

    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 |

    Reconstructing short-term plate-motion changes through time provides important geodynamical information, but data noise is a problem at fine temporal resolution. This study presents a trans-dimensional hierarchical Bayesian framework that eliminates noise without loss of temporal resolution.

    • Giampiero Iaffaldano
    • , Thomas Bodin
    •  & Malcolm Sambridge
  • Article |

    Kimberlites are volatile-rich magmas that form diverging pipes containing pelletal lapilli - well rounded clasts that consist of an inner seed particle. Gernonet al. suggest that pelletal lapilli are formed when fluid volatile-rich melts intrude into earlier volcaniclastic infill close to the diatreme root zone.

    • T.M. Gernon
    • , R.J. Brown
    •  & T.K. Hincks
  • Article |

    Dolomite sedimentary rock has lateral metre-scale periodic variations in porosity and composition, which may provide information on formation and transformation. This study suggests that such variations are fossilized chemical waves emerging from stress-mediated mineral-water interaction during sediment burial diagenesis.

    • Yifeng Wang
    •  & David A. Budd
  • Article
    | Open Access

    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
  • Article |

    The habitat where early humans, hominins, lived provides information about the early part of human evolution. In this study, sedimentological and stable carbon and oxygen isotope data suggest homininArdipithecus ramiduslived in a river-margin forest in a wooded grassland landscape at Aramis, Ethiopia.

    • M. Royhan Gani
    •  & Nahid D. Gani
  • Article |

    Active shortening in the Central Andes shifted from the western to the eastern margin between 10-7 Myr ago, but the mechanism of formation is still unclear. Here, using critical wedge theory and local-scale fault friction calculations, this shift is proposed to have been controlled by changes in erosion patterns.

    • Kevin Norton
    •  & Fritz Schlunegger
  • Article |

    Osteoderms are bones embedded within the dermis and are common in reptiles. Here, two osteoderms from the sauropod dinosaur Rapetosaurus indicate that the largest osteoderm known has an internal cavity equivalent to half its total volume and may have functioned as a mineral reserve in harsh environmental conditions.

    • Kristina Curry Rogers
    • , Michael D'Emic
    •  & Amanda Cagan
  • Article |

    SiO2 glass and helium are important in various fields of science and engineering. Sato et al. show SiO2glass to be less compressible in helium under high pressure, which may be relevant for the interpretation of high-pressure experiments and in the design of new materials.

    • Tomoko Sato
    • , Nobumasa Funamori
    •  & Takehiko Yagi