A tremor source on the San Andreas Fault produced an unusual sequence of low-frequency earthquakes until it was disrupted by the 2004 Parkfield earthquake; the peculiar recurrence pattern has now been modelled, showing that such slip behaviour occurs when the tremor asperity size is close to the critical nucleation size of earthquakes.

Biospheric relationships between production and consumption of biomass have been resilient to changes in the Earth system over billions of years. This relationship has increased in its complexity, from localized ecosystems predicated on anaerobic microbial production and consumption to a global biosphere founded on primary production from oxygenic photoautotrophs, through the evolution of Eukarya, metazoans, and the complexly networked ecosystems of microbes, animals, fungi, and plants that characterize the Phanerozoic Eon (the last ∼541 million years of Earth history).

Although iron- and sulfate-reducing bacteria in subsurface environments have crucial roles in biogeochemical cycling of C, Fe, and S, how specific electron donors impact the compositional structure and activity of native iron- and/or sulfate-reducing communities is largely unknown. To understand this better, we created bicarbonate-buffered batch systems in duplicate with three different electron donors (acetate, lactate, or glucose) paired with ferrihydrite and sulfate as the electron acceptors and inoculated them with subsurface sediment as the microbial inoculum.

This paper provides the state-of-the-art discussion of major aspects of the composition and evolution of the Earth’s core. A comparison of experimentally-derived density of Fe with seismological data shows that the outer liquid core has a homogeneous structure and a ~10% density deficit, whereas the solid inner core has a complex heterogeneous anisotropic structure and a ~5% density deficit. Recent estimations of the core-mantle boundary (CMB) and inner core boundary temperatures are equal to 3800–4200 K and 5200–5700 K, respectively.

The devastating magnitude-7.8 earthquake that struck Nepal in April caused surprisingly few landslides, researchers say — confirming the early impressions of scientists who raced to map collapsed terrain in the quake’s aftermath. However, there is still hot debate over just how severe the event’s impacts were.

In 2002, Munk defined an important enigma of 20th century global mean sea-level (GMSL) rise that has yet to be resolved.

In the present study, the strong motion data of the 4 April 2011 western Nepal earthquake (M 5.7) recorded by a dense network of 24 strong motion accelerograph stations have been used to estimate horizontal and vertical component of the peak ground acceleration (PGA) to better understand its bearing on the seismic hazard scenario of the Central Himalayan region.

Original Source

Current models to explain regional-scale landslide events are not able to account for the possible effects of the legacy of previous earthquakes, which have triggered landslides in the past and are known to drive damage accumulation in brittle hillslope materials. This paper tests the hypothesis that spatial distributions of earthquake-induced landslides are determined by both the conditions at the time of the triggering earthquake (time-independent factors) and the legacy of past events (time-dependent factors).

Glacial erosion is fundamental to our understanding of the role of Cenozoic-era climate change in the development of topography worldwide, yet the factors that control the rate of erosion by ice remain poorly understood. In many tectonically active mountain ranges, glaciers have been inferred to be highly erosive, and conditions of glaciation are used to explain both the marked relief typical of alpine settings and the limit on mountain heights above the snowline, that is, the glacial buzzsaw.