Volume 11 Issue 9, September 2018

Field work is an important and valued part of geoscience research, but can also serve as a source of stress. Careful planning can help support the mental health and wellness of participants at all career stages.

Plants influence geomorphology. Research on salt marshes suggests that feedbacks between geomorphic processes and life-history traits of plants produce species-specific signatures in the organization of biogeomorphic landscapes.

Strong anisotropy within the source region of deep earthquakes explains their apparent non-pure shear faulting mechanism.

There was minimal cooling in the North Atlantic Ocean during the Oligocene inception of the Antarctic ice sheet, according to a sediment record. This finding suggests asynchronous climate changes in the Northern and Southern hemispheres.

Robust evidence for a previously proposed sea-level fall and rise during the Last Interglacial is lacking, according to a synthesis. This calls estimates of high rates of sea-level rise at the end of the Last Interglacial into question.

Experiments suggest that magnetite precipitation on early Mars was accompanied by the release of H₂ that may have helped to warm the planet and stabilize liquid water at the Martian surface.

Biogenic aerosols produced by terrestrial vegetation substantially enhance global primary productivity of plants, according to integrated model analyses.

Deforestation by the ancient Maya led to a destabilization of organic carbon preserved in the underlying soils and reduced the magnitude of the soil carbon sink in this region.

The strength of the Southern Hemisphere westerly winds varied throughout the Holocene, according to a reconstruction from lake sediments, with periods of stronger winds coincident with higher atmospheric CO₂ levels.

Northern and Southern hemisphere temperatures were decoupled during the Eocene/Oligocene transition, suggests a sea surface temperature record from the North Atlantic.

The isotopic composition of sulfur minerals formed during the Archaean can be reconstructed from dissolved sulfur in rivers draining cratons. Analyses from Canada suggest that the Archaean sulfur cycle was in isotopic mass balance.

Microbial life colonized the land surface by 3.2 billion years ago, forming complex communities distinct from those in nearby marine environments, according to analyses of fossilized microbial mats in the Moodies Group, South Africa.

Fast-colonizing plants stabilize wetland landscapes, whereas slow-colonizing plants promote channel formation according to biogeomorphic model simulations and field observations.

The redox state of volcanic gases and melts can become decoupled during magma ascent, according to observations of gas emissions from Kīlauea’s lava lake, Hawaii. Cooling of fast-rising bubbles changes the abundance of redox-sensitive gas species.

Halogens in Siberian xenoliths show that plume–lithosphere interaction controls the volatile content of large igneous provinces. The seawater-derived volatiles, implicated in the end-Permian mass extinction, infiltrated the lithosphere during subduction.

The subduction system recorded by the Semail Ophiolite of Oman was initiated by far-field events, according to a comparison of the ages of the upper and lower plate material.

Radiation patterns for deep earthquakes could be a result of shear faulting mechanisms—similar to those for shallow earthquakes—but in highly anisotropic rock fabric, suggest seismic analyses.