Showing papers in "Earth and Planetary Science Letters in 2019"

TL;DR: The authors evaluated the utility of sedimentary mercury (Hg) contents as a proxy for fingerprinting ancient massive volcanism, which is often associated with biogeochemical perturbations.

TL;DR: The Izu-Bonin-Mariana (IBM) forearc contains a record of a widespread and short-lived subduction initiation event in the early Eocene as discussed by the authors.

TL;DR: In this article, Ni isotopic data for a comprehensive set of iron meteorites were analyzed, with a special focus on groups that have not been analyzed before and belong to the carbonaceous (CC) group.

TL;DR: In this article, the authors demonstrate that Hg in three OSB sections in South China (Qiliao, Yanzhi, and Jiaoye) is overwhelmingly associated with pyrite, as shown by r(Hg-TS) > 0.9 (versus r (Hg−TOC) Δ 199 Hg) values that are inconsistent with volcanic inputs.

TL;DR: In this paper, the authors analyzed six earthquake-induced landslide inventories with earthquake magnitude ranging between 6.6 and 7.9 Mw and developed magnitude-frequency curves to analyse the size distribution of landslides as a function of ground motion, distance from the seismic source (both fault trace and epicentre), local relief, and lithology.

TL;DR: In this article, an internal resistance-heated diamond-anvil cell (DAC) was employed to determine the melting temperature of pure iron up to 290 GPa, for the first time above 200 GPa by static compression experiments.

TL;DR: In this paper, the authors examined the major oxide and trace element composition of tonalite-trondhjemite-granodiorite (TTG) metamorphic rocks to assess evidence for secular change.

TL;DR: In this paper, the authors used Hf-Nd-Sr-Pb isotope analyses from 50 core samples to trace the evolution of the mantle source during the brief period of FAB-through-boninite magmatism immediately following subduction initiation.

TL;DR: In this paper, the chemical speciation of dissolved sulfur and the sulfur concentration at fixed oxygen and sulfur fugacities for a wide range of silicate melt compositions (from Fe-rich basalt to dacite) were determined using both X-ray Absorption Near-Edge Spectroscopy (XANES) and from the dependence of equilibrium sulfur concentration on the fS2/fO2 ratio measured by secondary-ion mass spectrometry (SIMS) and electron microprobe.

TL;DR: In this paper, a new δ 238 U dataset for carbonate rocks from the Lower Nama Group, Namibia, deposited in a shelf ramp succession during the terminal Neoproterozoic (∼550 to ∼547 Ma) is presented, which is consistent with an emerging picture of a dominantly anoxic Ediacaran ocean punctuated by brief ocean oxygenation events.

TL;DR: In this paper, the authors show that reaction softening promotes the replacement of strong minerals with phyllosilicates, and that this weakening originates at the grain-scale and is transmitted to the entire fault zone via the interconnectivity of the phylloshilicate-rich zones resulting in a friction as low as 0.1 μ 0.3.

TL;DR: In this article, a geochemical filter was introduced to identify clean, inclusion-free zircon and a new parameter δ K to constrain the deviation from the lattice strain model.

TL;DR: In this paper, the authors investigated quartzite flow laws based on data from 21 different experimental studies on samples deformed with added water at temperatures from 700 to 1200°C and found that the change in stress exponent indicates a transition in the rate-limiting process of dislocation creep.

TL;DR: In this paper, the redox state of glassy crystal-hosted melt inclusions from tephra and quenched lava samples from the Canary and Cape Verde Islands was investigated.

TL;DR: In this paper, the authors examined mercury chemostratigraphy, including mercury concentrations and isotopes, from high southern latitude and equatorial sections that span the Late Permian Changhsingian to Early Triassic Spathian substage successions; the Guryul Ravine section, Kashmir in northern India, and the Chaohu section in southern China.

TL;DR: In this article, the authors investigate the interaction between rock glacier creep and climatic forcing - temperature and precipitation - by developing a novel conceptual and numerical modelling approach and find that water from liquid precipitation and snow melt, rather than air temperature, is the main driver of variations in rock glacier drift.

TL;DR: In this paper, a typical VS-bearing section was found in the Lower Yangtze region, which contains ∼100 thin, interbedded volcanic ash layers across the Ordovician-Silurian (O-S) transition.

TL;DR: In this paper, the authors studied the effect of magma supply on an ultra-low mid-ocean ridge starting from quasi-melt-free detachment-dominated spreading, and transitioning to volcanic spreading as one nears prominent axial volcanos.

TL;DR: In this paper, the authors used thermogravimetry to determine that the frictionally heated sliding surface reached ∼850°C at the base of the 1.16 × 10 9 ǫ 3 Daguangbao landslide, triggered during the 2008 Ms8.2 Wenchuan earthquake.

TL;DR: In this article, the authors reconstruct paleoenvironments in the Xining Basin, NE Tibet, to show a long-term drying of the Asian continental interior from the early Eocene to the Oligocene.

TL;DR: The relationship between oxygen and evolution of early eukaryotes including algae and primitive animals in geological history has been debated, partly due to the varying estimates of oxygen levels in the mid-Proterozoic (ca. 1.8-0.8 Ga) ocean and atmosphere as discussed by the authors.

TL;DR: In this paper, the first-principles calculations based on density functional theory (DFT) were used to calculate equilibrium Ca isotope fractionation factors of Ca-bearing minerals.

TL;DR: This paper analyzed the Ba isotope composition of post-Marinoan barite horizons from Northwest Canada, Northern Norway, Brazil and South China and concluded that Ba in these horizons was sourced from a well-mixed, Ba-replete but SO4-poor reservoir that accumulated during the Marinoan Snowball Earth interval.

TL;DR: In this article, the authors improved the technique of the joint inversion of receiver function and gravity data and utilized it to improve the estimates of crustal thickness and Poisson's ratio in South China.

TL;DR: In this paper, a compilation of new calcium and magnesium isotope measurements in Marinoan cap dolostone successions worldwide was used to understand the geochemical variability of cap DOLostone units, including large excursions in carbon isotopes.

TL;DR: In this paper, phase relation models were used to constrain the fate of slab-derived carbonatite melts in the upper mantle, and the phase relation model demonstrated a reactive melting process in which the carbonatites influx increases in proportion by dissolution of olivine, orthopyroxene, garnet and precipitation of clinopyroxenes.

TL;DR: In this article, the role of mantle flow on subduction-related volcanism during back-arc extension was investigated using three-dimensional numerical models, and it was shown that for a time interval of about 10-15 Myr during backarc basin formation and spreading a wide convection cell brings mantle that has already partially depleted at the backarc to the mantle wedge.

TL;DR: The SHAWQ2k model as mentioned in this paper is based on a critical revision of the global archeomagnetic and volcanic dataset, which provides an improved description of the geomagnetic field during the last 2 millennia, and yields surprising outcomes about the emergence and development of the SAA.

TL;DR: In this article, the authors evaluate the efficacy of this model and other models for the origin of inner Solar System H2O by considering geochronological constraints on early Solar System history, constraints on primary building blocks of differentiated bodies based on nucleosynthetic isotope anomalies, and constraints from dynamical models of planet formation.

TL;DR: In this paper, a suite of new uranium (U) isotope data from marine carbonate rocks that span the entire mid-Proterozoic interval (∼1.8 to 0.8 Ga).