Articles tagged with Seismology
Researchers use geophones to estimate elephant numbers by detecting footfalls, providing a more accurate and time-efficient method than counting dung balls or aerial censuses. The new technique has the potential to improve conservation management and reserve planning in central Africa.
Scientists developed a new method to image the earth's rupture during the Dec. 26 Indian Ocean earthquake, providing a fresh perspective on the massive event. The technique uses first-arriving seismic waves to create detailed images in under 30 minutes, which could be used for public-warning and tsunami-alert systems.
Researchers estimated that the quake caused a massive 5-20 meter displacement along the 1,300-kilometer fault, leading to significant rearrangement of the Earth's surface. The tremors triggered devastating tsunamis killing over 300,000 people across Southeast Asia.
Scientists led by Professor Jeffrey J. Park have detected the natural tones from seismograms after the Sumatra-Andaman earthquake, providing information on Earth's deep mantle and core. The data supports a model of the earthquake that lasted about 10 minutes, with massive slabs of rock moving over 800 miles.
Researchers used various models to recreate the rupture history and variation along the fault, revealing the earthquake's length, epicenter, and speed. The study provided valuable insights into one of the largest earthquakes recorded on modern equipment.
The study provides a comprehensive analysis of the earthquakes, including the longest fault rupture and duration of faulting, as well as the seismic waves that traveled around the globe. The researchers also found that the earthquake caused the planet to vibrate with 'free oscillations,' like the ringing of a bell.
Researchers at the University of Nevada, Reno have developed a new method to calculate the probability of the San Andreas fault rupturing again within the next 30 years. The study suggests that there is a 20-70% chance of a large quake shaking southern California.
The Global Seismographic Network can track seismic signals in real-time, allowing researchers to compile and interpret information about potential hazards sooner. The network's unparalleled detail enables scientists to quickly determine the magnitude and location of an event in near real-time.
The simulation reveals how tsunamis strike coastlines with devastating force, deforming sea water and affecting the earth's surface. The Cornell Multigrid Coupled Tsunami model, or COMCOT, calculates sea surface elevation based on earthquake data and topography.
Researchers at the University of Nevada, Reno developed a model that estimates the impact of a large earthquake in Los Angeles by studying an earthquake in Kern County. The study found that the hanging-wall side of thrust-fault earthquakes experiences more extreme motion and damage than the footwall side.
Penn State researchers are conducting a project to develop a technique for detecting mine voids using seismic signals. The initiative aims to locate and record voids near existing coal mine tunnels, which could help prevent flooding incidents like the Quecreek disaster.
Fred Hilterman, a UH geophysics professor, is being honored with the Cecil Green Enterprise Award for his innovations and dedication in advancing geosciences. He co-founded the Geophysical Development Corporation (GDC), which integrated petrophysical and seismic data, and developed AVO technology to determine the earth's composition.
A team of seismologists at Arizona State University has discovered a highly active region beneath Earth's surface, where the mantle meets the liquid iron core. The study found unusual layering in the deep interior, which may hold clues about how the interior churns and convects.
The Alpine fault begins as a single fault, unlike most other strike slip faults which form from multiple small faults. It exhibits significant seismicity at the southern and northern ends but is relatively aseptic in the central portion.
Researchers found evidence of ancient seismic stresses still at work in Washington state's Puget Sound region, including surface folds and deformation of the Seattle uplift. The study provides greater understanding of the region's tectonic stresses and geological processes.
Research papers in Geophysical Research Letters and Journal of Geophysical Research-Atmospheres have shed light on various atmospheric phenomena. Brown et al.'s study found near-equal rates of nitric acid formation during day and night, while Chatfield et al. attribute seasonal ozone density over the South Atlantic to pollution sources...
The web-based program calculates thermal radiation, seismic shaking, ejecta deposition, and air-blast effects based on user input distance from impact site. It provides detailed descriptions of damage severity, including ignition times for grass and wood, shaking intensity levels, and debris particle sizes.
The new system uses high-frequency seismic waves to detect buried mines, distinguishing them from soil and ground clutter. Researchers have demonstrated its advantage in laboratory and limited field tests, with promising results at government testing facilities.
A recent catastrophic landslide on Kilauea has created a debris buffer that stabilizes the Hilina slump, reducing the likelihood of future collapse. The buffer was formed when a detached piece of the mountain slid away and settled beneath the ocean, creating a broad, bench-like structure.
Scientists mapped locked zones on the Cascadia megathrust, revealing a 56-mile swath of land faces a greater threat from earthquakes than previously thought. Another major earthquake is expected within the next 200 to 800 years, putting rapidly growing inland cities at risk.
Scientists have developed a new adaptation of seismic reflection profiling to create detailed pictures of oceanic features, including eddies and internal waves. This technique has the potential to improve our understanding of ocean mixing and its role in climate modeling.
Researchers chart seismic effects on water levels to better understand the impact of earthquakes on hydrology. The study found that wells and aquifers respond differently to earthquakes than surface water, with effects recorded at greater distances.
Researchers used GPS receivers to detect seismic waves from a 7.9 magnitude earthquake in Alaska and measure their impact on the US and Canada, revealing large surface displacements. The study showcases the versatility of GPS technology for tracking seismic activity and monitoring natural disasters.
Researchers at Columbia University suggest that ancient faults in the Wabash Valley Fault System may be re-activated, causing recent earthquakes. The study analyzed seismic data from a June 2002 earthquake and found evidence of strike-slip faulting on a near-vertical fault plane at 18 km depth.
Scientists from University of Ulster's Geophysics Research Group warn of substantial loss of life possible in Bingol city after Thursday's earthquake, citing increased seismic risk. The team identified two highly stressed areas on the East Anatolian Fault Zone as most likely locations for future large events.
A new early-warning system designed for southern California could give people up to 40 seconds of advanced notice of major earthquakes, allowing them to take shelter or evacuate. The system uses low-energy P-waves that travel faster than damaging S-waves and can provide precious seconds to react.
The new study modeled earthquakes using computer simulations, finding that sections of the fault with increased material strength can focus energy to an unexpected degree. This results in intense bursts of seismic waves posing significant hazards to nearby structures.
Marine geologists will study Kick'em Jenny, a highly active volcano in the Caribbean, using advanced instrumentation and technologies. The two-week research cruise will investigate the volcano's acoustic signals, biological communities, and geological features.
Researchers have discovered that an earthquake can cause damage to a neighboring fault line, potentially leading to more earthquakes. The study, led by UCLA's Vidale, measured seismic wave speed to detect this effect and found it in the Landers fault, which is 10 miles away from the Hector Mine fault.
Researchers found that small-magnitude earthquakes and micro-cracking in a region called the process zone precede propagation, followed by nucleation of the rift axis and upwelling of magma. This new understanding can be applied to more complex rift settings in oceans and continents.
Researchers have made key findings about the San Andreas fault system, predicting major earthquakes within 30 years for certain areas. The study, which analyzed paleoseismic data from 10 sites, suggests that at least 120 miles of the southernmost section of the fault may rupture in a large earthquake of magnitude 7.6 to 7.8.
The University of California, Berkeley, has deployed a first permanent broadband earthquake monitor in Monterey Bay, which will measure earthquake activity from the ocean side of the fractured fault zone. The instrument aims to reveal new information about seismic activity on the Pacific Plate and improve understanding of earthquakes.
Geologists reconstructed the Eridanos Delta's course and discovered that climate influenced its development. Numerical models predict river dynamics over hundreds of years, helping to answer questions about climate change impacts on rivers.
Researchers have made significant discoveries about the San Andreas Fault using a new technique for seismic imaging. The study has provided valuable information on the properties of rocks near the surface and the deep fault line, shedding light on the potential risks and opportunities associated with drilling through the fault.
Researchers identify a consistent seismic pattern suggesting a recurrence time of 1,500-2,500 years for the 1356 Basel earthquake. This discovery could help safeguard infrastructure and fine-tune emergency procedures before a potential major earthquake strikes.
The National Science Foundation (NSF) has funded a virtual collaborative research network called NEESgrid. This initiative aims to improve seismic design and hazard mitigation by providing researchers with access to cutting-edge computational tools and experimental equipment, enabling them to share data and resources.
Scientists investigated subducting lithosphere and deep earthquakes near Fiji, finding a group of deep earthquakes off to the side that cannot be connected to the actively subducting lithosphere. The researchers suggest that similar slabs may exist elsewhere, preserving a significant primordial component of the mantle.
Researchers used computer simulations to analyze the Chicxulub impact crater, revealing that it may have behaved like a fluid during its formation. This finding could help explain the complex internal structures observed in the crater and shed light on the environmental effects of large-impact craters.
Researchers found that the northern Hayward fault slips at a rate of 5-7 millimeters per year, similar to the surface, indicating it is not locked and releasing built-up strain. This reduces the threat of a major quake on this segment, but other hazards remain high.
A new analysis by University of Colorado at Boulder professor Karl Mueller indicates a high threat of large earthquake in the New Madrid seismic zone. The study gathered evidence on a pivotal 'blind-thrust' fault and found a slip rate of nearly 45 feet over 2,300 years, posing significant risks to Memphis and St. Louis.
A team of researchers is using seismic equipment to map the Earth's structure beneath the Rocky Mountains, aiming to understand how ancient land masses collided to form the continent. By analyzing density and material properties of rocks, they hope to visualize the structure of what lies far under the Earth's surface.
A team of scientists will conduct seismic experiments along a 600-mile route, using specialized instruments and explosions to create detailed profiles of the Earth's crust. The project aims to gain insight into the formation of the Rockies and improve knowledge of earthquake hazards, natural resources, and water resources.
USGS scientists will present findings on prehistoric earthquakes, seismic hazards, and the structure of the Seattle basin. The presentations will provide insights into the probabilities for future earthquakes in the Seattle area and the current seismic hazards of the Pacific Northwest.
New study using GPS satellites tracks ground motions in Midwest seismic zone, revealing little to no motion across the area. The results suggest National Seismic Hazard maps should be revised to reflect lower estimates of earthquake risk, potentially leading to cost savings for new construction.
Researchers have discovered two distinct rock types at the base of the mantle, which are moving laterally and interacting with the liquid iron outer core. This finding has significant implications for plate tectonics and our understanding of the Earth's geological history.
Researchers at Carnegie Institution use X-ray diffraction to determine iron's elasticity at high pressures, which could explain seismic anisotropy in the inner core. The findings suggest the inner core is close to melting and may contain additional components with low shear-wave velocities.
Scientists have provided direct evidence that the Earth's innermost core is solid, contradicting a long-held assumption of a liquid core. This finding was made possible by advances in instrumentation and computer capabilities, allowing researchers to detect the characteristic vibrations of a solid core.
Researchers from the Max Planck Institute for Chemistry studied the stability of materials relevant to the lower mantle under very high pressures and temperatures. Their findings indicate that partial melting is more likely than previously thought to explain seismic anomalies in this region.
A strong consensus has emerged among US seismologists that the seismic network would have detected a blast equivalent to 800 tons of TNT, leading some experts to conclude that India's second round of tests were small and designed to test nuclear bomb components. Pakistan conducted its own nuclear tests shortly after.
The USGS has released a new seismic hazard map for the Western Hemisphere, providing a comprehensive tool for assessing potential earthquake damage. The map is the result of nearly a decade of cooperative work by scientists from around the world and will be available online and in various publications late this year.
A new study published in Nature has provided the first evidence of reduced sediment amplification in Southern California during large earthquakes, shifting the debate towards the engineering view. The research suggests that seismic hazard posed by local sediments may be underestimated in current engineering practices.
Scientists are studying the Hayward Fault, South Bay Stepover, and Loma Prieta to better understand their movement patterns. They found that some portions of the fault have locked up, leading to unrelieved stress at greater depths, while others exhibit complex creeping behavior.
Researchers Paul Richards and Won-Young Kim analyze seismic data to verify the Comprehensive Test Ban Treaty, concluding the event was an earthquake with 'excellent' monitoring capability
Scientists from the National Science Foundation and IRIS have ruled out cult activities and nuclear detonations as causes of a 1993 Australian seismic event. They now believe that an iron meteorite of about two meters in diameter could have created the tremors, but no crater has been found.
Researchers analyzed seismic data to determine cause of 1993 event in Australian outback. An iron meteorite over 3 meters in diameter is suggested as possible cause.
The NSF is installing 250 ground-based monuments to track satellites and study earth movements in Southern California, enabling scientists to follow Earth's crust movements with unprecedented detail. The network will provide valuable insights into earthquake potential and strain buildup, helping to identify areas of high seismic activity.
The USGS National Earthquake Information Center lost near real-time data from the AT&T Telstar 401 satellite, but regional networks and cooperation with other seismic networks maintained earthquake monitoring. Smaller earthquakes are now harder to track due to slower reporting times.
The California Department of Conservation has released six preliminary seismic hazard zone maps, highlighting areas susceptible to landslides and liquefaction in San Francisco and Southern California. The maps will help local governments identify areas requiring geologic or soil investigation before urban development permits are issued.
The US has signed the Comprehensive Test Ban Treaty, which will be verified through a global seismic monitoring system. The treaty bans nuclear testing in all environments except underground, and the global network is being installed by IRIS and the National Science Foundation to detect seismic events of magnitude 4.25 or larger.