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Categories: Geoscience: Earthquakes, Geoscience: Geomagnetic Storms
Published What are the characteristics of foreshocks for large earthquakes?



Seismologists agree that foreshocks are the most widely identified signal of an upcoming mainshock earthquake. But do these foreshock sequences have distinctive characteristics that separate them from aftershock sequences, and could these characteristics be used to help forecast mainshocks?
Published Multiscale rupture growth driven by a complex fault network during the 2023 Türkiye and Syria earthquake doublet



Researchers analyzed the source processes of the twin earthquakes that caused extensive damage in Türkiye and Syria on February 6, 2023. The results revealed that a complex fault network with bends, steps, and branches controlled the propagation speed and direction of the rupture, leading to hierarchical small to large rupture growth.
Published Sinking seamount offers clues to slow motion earthquakes



The first ever 3D seismic imaging of a subducting seamount shows a previously unknown sediment trail in Earth's crust off the coast of New Zealand. Scientists think the sediment patches help release tectonic pressure gradually in slow slip earthquakes instead of violent tremors. The findings will help researchers search for similar patterns at other subduction zones like Cascadia in the U.S. Pacific Northwest.
Published When soft spheres make porous media stiffer



Porous media such as concrete physically represent a spherical packing of different components -- in this case cement, rock and water. The mechanical properties of such mixtures are still difficult to calculate due to their discretized nature. A team has now been able to investigate an unexpected property of mixtures of granular media consisting of soft and stiff spherical particles. For this purpose, a combination of ultrasound investigations and X-ray computed tomographic imaging was employed, allowing a three-dimensional (3D) characterization and evaluation. The discovery could contribute to safer future building in earthquake zones.
Published Scientists unearth 20 million years of 'hot spot' magmatism under Cocos plate



A team of scientists has observed past episodic intraplate magmatism and corroborated the existence of a partial melt channel at the base of the Cocos Plate. Situated 60 kilometers beneath the Pacific Ocean floor, the magma channel covers more than 100,000 square kilometers, and originated from the Galápagos Plume more than 20 million years ago, supplying melt for multiple magmatic events -- and persisting today.
Published Plate tectonics not required for the emergence of life



New finding contradicts previous assumptions about the role of mobile plate tectonics in the development of life on Earth. Moreover, the data suggests that 'when we're looking for exoplanets that harbor life, the planets do not necessarily need to have plate tectonics,' says the lead author of a new paper.
Published Study explains unusual deformation in Earth's largest continental rift



Computer models confirm that the African Superplume is responsible for the unusual deformations, as well as rift-parallel seismic anisotropy observed beneath the East African Rift System.
Published Campi Flegrei volcano edges closer to possible eruption



The new study used a model of volcano fracturing to interpret patterns of earthquakes and ground uplift, and concluded that parts of the volcano had been stretched nearly to breaking point.
Published Bubble, bubble, more earthquake trouble? Geoscientists study Alaska's Denali fault



Geochemists report findings from collected and analyzed helium and carbon isotopic data from springs along a nearly 250-mile segment of Alaska's Denali Fault. The fault's mantle fluid flow rates, they report, fall in the range observed for the world's other major and active strike-slip faults that form plate boundaries.
Published 'Segment-jumping' ridgecrest earthquakes explored in new study



Seismologists used a powerful supercomputer that incorporated data-infused and physics-based models to identify the link between the 2019 Ridgecrest earthquakes.
Published Impact of ancient earthquake revealed



By combining the scientific powerhouses of genetics and geology, researchers have identified a new area of coastal uplift, which had been hiding in plain sight.
Published Creating a tsunami early warning system using artificial intelligence



Researchers develop an early warning system that combines acoustic technology with AI to immediately classify earthquakes and determine potential tsunami risk. They propose using underwater microphones, called hydrophones, to measure the acoustic radiation produced by the earthquake, which carries information about the tectonic event and travels significantly faster than tsunami waves. The computational model triangulates the source of the earthquake and AI algorithms classify its slip type and magnitude. It then calculates important properties like effective length and width, uplift speed, and duration, which dictate the size of the tsunami.
Published Ridgecrest faults increasingly sensitive to solid Earth tides before earthquakes



Faults in the Ridgecrest, California area were very sensitive to solid earth tidal stresses in the year and a half before the July 2019 Ridgecrest earthquake sequence.
Published Puerto Rico tsunami deposit could have come from pre-Columbian megathrust earthquake



Tsunami deposits identified in a coastal mangrove pond in Northwest Puerto Rico could have come from a megathrust earthquake at the Puerto Rico Trench that occurred between 1470 and 1530, according to new research.
Published Turkey's next quake: Research shows where, how bad -- but not 'when'



Using remote sensing, geophysicists have documented the massive Feb. 6 quake that killed more than 50,000 people in Eastern Turkey and toppled more than 100,000 buildings. Alarmingly, researchers found that a section of the fault remains unbroken and locked -- a sign that the plates there may, when friction intensifies, generate another magnitude 6.8 earthquake when it finally gives way.
Published New USGS-FEMA report updates economic risk from earthquakes



Even though most of the economic losses are concentrated in California and along the West Coast due to that region's high seismic hazard levels, significant population, and building exposure, earthquake risk is spread throughout the country. For example, there is a combined $3.1 billion per year in projected losses across the central U.S., Rocky Mountain region, Alaska, Hawaii, Puerto Rico and the Virgin Islands.
Published Plate tectonic processes in the Pacific and Atlantic during the Cretaceous period have shaped the Caribbean region to this day



Earthquakes and volcanism occur as a result of plate tectonics. The movement of tectonic plates themselves is largely driven by the process known as subduction. The question of how new active subduction zones come into being, however, is still under debate. An example of this is the volcanic Lesser Antilles arc in the Caribbean. A research team recently developed models that simulated the occurrences in the Caribbean region during the Cretaceous, when a subduction event in the Eastern Pacific led to the formation of a new subduction zone in the Atlantic. The computer simulations show how the collision of the old Caribbean plateau with the Greater Antilles arc contributed to the creation of this new Atlantic subduction zone. Some 86 million years ago, the triggered processes subsequently resulted in a major mantle flow and thus to the development of the Caribbean large igneous province.
Published Warm liquid spewing from Oregon seafloor comes from Cascadia fault, could offer clues to earthquake hazards



Oceanographers discovered warm, chemically distinct liquid shooting up from the seafloor about 50 miles off Newport. They named the unique underwater spring 'Pythia's Oasis.' Observations suggest the spring is sourced from water 2.5 miles beneath the seafloor at the plate boundary, regulating stress on the offshore subduction zone fault.
Published Was plate tectonics occurring when life first formed on Earth?



Researchers used small zircon crystals to unlock information about magmas and plate tectonic activity in early Earth. The research provides chemical evidence that plate tectonics was most likely occurring more than 4.2 billion years ago when life is thought to have first formed on our planet. This finding could prove beneficial in the search for life on other planets.
Published Messages about the 'felt intensity' of earthquakes via app can potentially assist early disaster management


After an earthquake, it is crucial in the early phase of disaster management to obtain a rapid assessment of the severity of the impact on the affected population in order to be able to initiate adequate emergency measures. A first quick and good assessment of whether an earthquake causes severe or minor damage can often be given after only 10 minutes by information from affected people about the 'felt intensity' of the earthquake.