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Deposition of 1.2-billion-year-old Indian limestone in shallow seas near the poles imply balmy conditions of more than 15 °C and significantly higher atmospheric greenhouse gas concentrations, which expands the spectrum of Earth’s climatic extremes.

A 3D stochastic declustering algorithm, applied to data from the dense seismic array at the Alto Tiberina Fault system, Italy, suggests the difference between earthquake size distributions of independent and triggered seismicity is not an artifact.

A proxy is developed for oxygen levels in seawater, based on U-Pb dating of dolomite. It shows a step-increase in O2 400 million years ago, suggesting that oceans were largely oxygen-limited at the ‘dawn’ of animal life.

The Isua Supercrustal Belt in Greenland hosts sedimentary rocks that were deposited 3.7 billion years ago in the forearc environment of an active convergent plate boundary, suggesting subduction-related plate tectonics in the Eoarchean, as indicated by geochemical data and tectonostratigraphic analyses of an 80-m drill core.

High-pressure and high-temperature experiments suggest a redox-controlled partitioning behavior of platinum group elements between sulfide liquid and basaltic melt, which could help constrain the formation mechanisms of magmatic sulfide deposits

Tectonic processes can lead to the formation of semi-enclosed seas and the deposition of extensive salt deposits. This Review explores the drivers and impacts of the Mediterranean Messinian salinity crisis, including previously underconsidered impacts on the global carbon cycle.

The Cenozoic eastward growth of the Tibetan Plateau can be explained by slab tear and the resulting mantle flow beneath the eastern region, according to analysis of seismic tomography, tectonic and magmatic records of the Indian mantle lithosphere.

Northeast Atlantic climate shifted into the Quaternary Ice Age around 2.6 Myr ago. Here, the authors use 3D seismic data from the northern North Sea to document detailed changes in continental-margin sedimentary architecture spanning the transition from a fluvially dominated environment to an icehouse world.

Earth’s oldest known felsic rocks formed by partial melting at low pressures and high temperatures caused by impact melting of mafic Hadean crust, according to phase equilibria and trace element modelling.

Why Earth’s crust only started becoming widely preserved in the Eoarchaean, 500 Ma after planetary accretion, is poorly understood. Here, the authors document a shift to juvenile magmatic sources in the early Eoarchaean, linking crustal preservation to the formation of stabilising melt-depleted mantle.

Methane release across the Arctic continental shelf has been attributed to modern dissociation of gas hydrate, accelerated by ocean warming. Here, the authors show that thermogenic methane was stored as subglacial gas hydrate during the last glaciation, and subsequently released following ice sheet retreat.

The role of cohesion is vital to our understanding of how sedimentary bedforms evolve. Here, the authors show that microorganisms within the sediment affect cohesion and demonstrate that ripples can take up to one hundred times as long to develop when extracellular polymeric substances are present.

Testing feedbacks between climatic and geological processes are challenging. Here, the authors show that geomorphological features of the southern Red Sea margin are best interpreted by a feedback cycle between orographic precipitation, mid-ocean spreading and coastal magmatism, and that the feedback is enhanced by the trade wind.

The Argyle deposit erupted 1.3 billion years ago into an ancient rift at the edge of a craton. Argyle coincided with supercontinent breakup, highlighting the link between diamond emplacement, former rifts and continental breakup.

Experiments under simulated hydrothermal conditions suggest that the mineral fluocerite may serve as an intermediate phase that fractionates the rare earth elements in ore-forming systems.

The flow of ice streams leaves traces in the stratigraphy of the ice sheets. Made visible by radar, they reveal the history of the upper North East Greenland Ice Stream. The ice stream is found to have existed in its current form for only about the last 2000 years.

Recycling of sedimentary phosphorus driven by increasing oceanic sulfide availability contributed to the persistent oxygenation of Earth’s atmosphere, according to analysis of Archean drill-core samples and biogeochemical modelling

This paper shows that faults comprised of heterogeneously distributed materials, as is typical for tectonic faults in nature, are weaker and more unstable than equivalent faults where the materials are homogeneously mixed together.

Back-arc spreading centre jumps have been suggested to be controlled by a number of different drivers. Here, the authors, using 3D numerical models, show that transform faults can trigger back-arc spreading centre jumps, without the need of any ad hoc factors.

Weakly coupled subduction zones may generate earthquakes that lead to tsunamis, but their structure and seismicity are poorly constrained with the Ryukyu subduction zone as one such example. Here, Arai et al. present seismological evidence from Ryukyu showing megathrust faults and low frequency earthquakes.

Tidal channel networks mediate the exchange of water, nutrients, sediment and biota between an estuary and marshes. Here, the authors show that the presence of vegetation on the marsh platform contributes to the formation of an efficient channel network.

Viscous deformation is a potentially prevalent mechanism of fault lubrication during earthquakes, according to laboratory experiments that simulate seismic faulting of various rock-forming minerals.

The second oceanic anoxic event occurred 94 million years ago and constituted a very large perturbation of the Earth's carbon cycle. Here, the authors study carbon isotopes and degrees of pyritization and demonstrate that, unlike other oceans, the Pacific remained oxygenated for most of this period.

Slow slip events have been observed in different subduction zones, but their relationship to megathrust earthquakes remains elusive. Here, the authors postulate that a transient event may have led to the 2011 Tohoku earthquake as the hypocentre falls within a zone of positive Coloumb stress change.

The influence of surface ponding on the interior of ice shelves is currently unknown. Here, the authors combine surface and borehole geophysics on the Larsen C Ice Shelf, Antarctica, with remote sensing and modelling and show how pond refreezing increases ice shelf density and temperature.

The behaviour of subducted carbonates at high pressures within the Earth is still poorly understood. Here, the authors present experimental and theoretical evidence of a new carbon–oxygen bond in a high-pressure mineral phase, which has implications for the viscosity and mobility of carbonate melts.

Our understanding of the internal dynamics of the Earth is limited by the lack of seismic data available from oceanic domains. Here, the authors use observations from floating submarine seismographs to show that this technique may provide seismic data to fill the gaps in our knowledge.

Recent studies suggest that the Moon is not as volatile-poor as once thought, and that volatile elements should be concentrated in crustal materials. Here, the authors present Zn isotopic and abundance data as evidence of evaporative loss of volatiles during formation of the Moon, supporting alternative models.

Suspended sediment currents travel through channels on the ocean floor to deliver enormous volumes of sediment to the deep ocean. Here, using a new approach for scaled laboratory experiments, the authors show how feedback between these currents and their deposits drive the formation of these submarine channels.

Utilizing supercritical geothermal water could multiply energy production, but the abundance, location and size of such resources is unclear. Here, the authors present numerical simulations and suggest that supercritical water may play a key role in removing heat from all magmatic intrusions.

Molar tooth structures are common in early- to mid-Proterozoic carbonates but extremely rare in rocks younger than 750 Ma. Here, the authors show molar tooth carbonate formation is related to benthic methane fluxes.

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.

Following the Mw6 South Napa earthquake in California, previously dry streams and springs began to flow. Here, the authors present data from repeated stream surveys and laboratory measurements and suggest that the new flows originated from groundwater in the mountains and were released by the earthquake.

It is unclear why some ocean island basalts at ‘hotspots’ have low ³He/⁴He ratios similar to mid-ocean ridge basalts. Here, the authors perform convection calculations and show that these isotopic ratios can be reproduced by the episodic entrainment of deep isolated mantle reservoirs into thermal plumes.

Meteorites falling on Earth today are believed to represent 100–150 parent bodies. Within 470 Myr ago sediments at a limestone quarry in Sweden, Schmitz et al. have found and identified a new type of meteorite based on chromium and oxygen isotopes sourced from a previously unknown parental body.

On 1 April 2014 the Mw 8.1 Iquique earthquake seemed to close the well-recognized northern Chile seismic gap, producing only a small rupture. Here, the authors present seismic reflection and multibeam bathymetry data from the area suggesting that seamount subduction played a role in halting the rupture.

The internal textures of columnar-jointed lava flows and intrusions are poorly understood. Mattssonet al. propose a melt-migration model for Icelandic basalt driven by crystallization and volume decrease inside cooling columns, which explains the macroscopic features observed in columnar-jointed basalts.

A range of mechanisms has been proposed for large-scale folding in polar ice sheets. Here, using new three-dimensional reconstructions of such folds in the onset region of the Greenland Petermann Glacier, the authors show that these formed due to flow convergence and the high mechanical anisotropy of ice.

Understanding of the Earth’s interior requires insight into the thermal properties of silicate melts under high pressure. Here, the authors present high-pressure spectroscopic measurements of iron-enriched dense silicate glasses and infer the radiative conductivity of dense melts at the core–mantle boundary.

Copepod crustaceans are extremely abundant but fossilize poorly given their fragility; the earliest known fossils are from the Cretaceous period. Selden and colleagues report copepod fossils dating from the Carboniferous in a bitumen clast in Oman, extending their fossil record by 188 million years.

The Arctic Mid-Ocean Ridge spreads extremely slowly and hydrothermal vent fields have not been reported in its vicinity. Pedersenet al. describe a black smoker vent field with large hydrothermal deposits and novel fauna distinct from those found in similar environments in the Atlantic.

The rapid decay of Earth’s dipole magnetic field has recently captured the public imagination. Here, the authors present a southern hemisphere magnetic record from South African Iron Age sites using oriented samples in the floors and suggest that the anomalous field behaviour is not just a recent feature.

Subduction is a main component of Phanerozoic plate tectonics, although the timing of initiation is controversial. Here, the authors present microstructural data from two 3.72 billion year old dunite lenses of Isua in Greenland, which suggest that subduction was already in operation during the Eoarchaean.

Recently observed rates of climatic change are typically much higher than those inferred for the geological past. Here, the authors show that maximum rates of climate change inferred from geological data are likely erroneously underestimated.

To date, covariance of carbonate and organic carbon isotope records has been assumed to denote fidelity of the original signal. This study shows that post-depositional alteration can create strong correlations, raising doubts about the use of correlated records to imply important changes in past global carbon cycling.

Tidewater glacier calving is assumed to be dependent on ice dynamics, but direct evidence is lacking. Here, Luckman et al. use satellite data to derive frontal ablation rates for dynamically contrasting Svalbard glaciers, and show that frontal ablation rate varies primarily with sub-surface ocean temperature.