New tool for monitoring nuclear tests:
Corresponding author: Stephen J. Arrowsmith of Los Alamos National Laboratory.
California’s Hayward Fault System Examined:
For Northern California, the Hayward Fault System is considered to pose the greatest risk for producing a major quake in the next 30 years. It is necessary for seismologists to understand the structure of the East Bay and the mechanics of its motion in order to anticipate what will happen during an earthquake along the Hayward Fault. Scientists from USGS-Menlo Park created the most detailed 3-D model to date of the upper crust in the East Bay and geometry of the Hayward Fault. The model reveals the motion of small Hayward Fault earthquakes to be very similar to the over-all motion of the fault, with no complexities that could bound or restrict the rupture zones of large earthquakes. Seismic hazard assessments should therefore plan for earthquakes anywhere along the fault. Further, although the Hayward and Calaveras Faults are not connected at the surface, the model revealed a smooth connection between the Hayward and Calaveras Faults at depths greater than about 3 miles. Therefore, seismic hazard assessments should assume scenario earthquakes that span parts of both faults.
Authors: Jeanne L. Hardebeck, Andrew J. Michael, and Thomas M. Brocher of USGS-Menlo Park, California.
Long-term seismic behavior of an active fault: what can we learn from a 12,000-yr-long paleo-seismic record?
Daëron and colleagues from Institut de Physique du Globe de Paris (France) present results of the first paleoseismic study of the Yammoûneh fault, which is the main on-land segment of the Levant fault system (or "Dead Sea fault") in Lebanon, a region tectonically similar to the "Big Bend" in the San Andreas fault. This area offers a long historic record that spans more than 2000 years of activity. Researchers sought to answer several questions about the frequency and magnitude of historical quakes and to understand the mechanisms at work that govern the faults. They present evidence that the latest event was the great A.D. 1202 earthquake and resolve unanswered questions about the frequency of seismic activity. Large earthquakes on different fault segments appear to cluster temporally within a couple of centuries, followed by millennial spans of relative quiescence. Authors conclude that regional risk assessment needs to prepare for the possibility of a large (M>7) earthquake striking this densely populated region in the coming century.
Corresponding author: Mathieu Daëron, currently at Caltech in Pasadena, CA
Nan Broadbent | EurekAlert!
In times of climate change: What a lake’s colour can tell about its condition
21.09.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)
Did marine sponges trigger the ‘Cambrian explosion’ through ‘ecosystem engineering’?
21.09.2017 | Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
25.09.2017 | Physics and Astronomy
25.09.2017 | Health and Medicine
22.09.2017 | Life Sciences