Articles tagged with Geologic History
Geophysicists Paul Silver and Mark Behn propose a new theoretical model that plate tectonic motions have stopped in Earth's geologic history, suggesting an intermittent process. This finding could impact our understanding of earthquakes, volcanism, and the formation of continents.
Scientists propose that plate tectonics may have halted or slowed down in the distant past and could do so again due to changes in ocean basin closure. This idea challenges current models and may explain differences in igneous rock formation and continental evolution.
Scientists have discovered a possible explanation for Mars' limestone-free climate: sulfur dioxide in the atmosphere. The greenhouse gas interfered with carbonate rock formation, but led to the creation of silicates and sulfites instead.
Researchers have successfully drilled four boreholes into the ocean floor near a major earthquake fault zone in Japan. The team collected geophysical information about the rock layers while drilling, revealing unexpected differences in physical stress conditions between active and inactive parts of the plate boundary.
Researchers found a small but significant amount of oxygen in the oceans and atmosphere 2.5 billion years ago, with oxygen nearly undetectable just before that time. The discovery provides compelling evidence for a shift in the oxidation state of the surface ocean 50 million years before the Great Oxidation Event.
The NanTroSEIZE expedition aims to retrieve geological samples and provide scientific data from the Nankai Trough fault zone. The program will drill deeply into the Earth to observe earthquake mechanisms in a well-known subduction zone, providing new insights into naturally occurring processes responsible for earthquakes.
A recent study found that media accounts of past earthquakes, such as the M7.6 Bhuj, India earthquake of 2001, can be misleading due to a natural bias towards dramatic effects. The research compared written accounts with ground-based surveys and concluded that the media bias can be significant, particularly at stronger shaking levels.
A geophysicist from Rensselaer Polytechnic Institute urges officials to consider all subduction-type tectonic boundaries as lethal due to the unpredictability of massive earthquakes. The expert highlights the importance of warning systems and educational outreach to coastal communities to mitigate the impact of tsunamis.
Researchers at the University of Nevada used precariously balanced rocks to test seismic hazard predictions, measuring forces and angles to determine when an earthquake has not occurred for a long time. The study provides important information on seismic hazards in areas throughout the West, including data on ground-motion probability ...
A team of researchers has discovered that ancient rocks from Quebec, Canada, contain iron carbonates believed to have formed in an atmosphere with extremely high CO2 levels. This suggests that high concentrations of greenhouse gases may have helped Earth avoid global freezing in its youth.
Scientists analyzed ancient rocks from Hudson Bay in Quebec to confirm that high concentrations of greenhouse gases could have sustained surface temperatures above freezing 3.75 billion years ago. The study suggests that carbon dioxide played a crucial role as the Earth's 'thermostat' to support life on the planet.
The January special issue of BSSA focuses on the 2004 Sumatra earthquake, which is the best recorded large earthquake in history. The study reveals that great earthquakes can occur in various types of subduction zones, not just fast and young ones.
A new study suggests that early Earth haze could have provided a substantial source of organic material useful for emerging life on the planet. The researchers found that hazy conditions could have produced a similar organic haze over a wide range of methane and carbon dioxide concentrations.
Scientists have proposed a new theory that combines deadly sudden catastrophes (pulses) with longer, steadier pressures on species (presses) to explain Earth's mass extinctions. The Press/Pulse theory suggests that these combined events are necessary for big extinctions to occur.
A team of scientists from Ohio State University has discovered a massive crater, hidden beneath the East Antarctic Ice Sheet, which could date back to the Permian-Triassic extinction event. The crater is estimated to be four times wider than the Chicxulub meteor that may have killed the dinosaurs.
A new study provides an explanation for continental plate breakups, showing that they often occur along preexisting lines of weakness created during earlier collisions. The research uses geochemical fingerprinting to demonstrate this principle, shedding light on the history of the Rheic Ocean.
New Jersey Institute of Technology physicists have used Earthshine observations to study changes in the earth's climate, with a focus on cloud cover and global warming. The research also has implications for the search for life on other planets, as evidenced by the detection of oxygen, water, and ozone in the Earth's spectrum.
The study found that the 2004 earthquake was caused by rupture of a 1,000-mile stretch of the megathrust, spanning up to 93 miles at the surface. This has global implications for understanding earthquake hazards and may require reassessment of subduction zones previously thought to be at low risk.
Researchers found evidence of increased clay mineral deposition in the oceans during a 200 million year period, which preceded the first animal fossils about 600 million years ago. The study suggests that an increase in oxygen concentration in the atmosphere was necessary for animal life to arise.
A Berkeley lab scientist has found a spike in micro-earthquakes followed by relative calm months before a large quake occurred. This discovery may help predict destructive earthquakes within a shorter time frame than current statistical tools.
A new study published in Science Express suggests that early Earth likely had continents and was habitable, with substantial continental crust forming by 4.4-4.5 billion years ago. The researchers used hafnium as a tracer element to infer the existence of early continental formation on Earth.
Researchers are using a NERC grant to study the unique creatures that live in hydrothermal vents, which could hold the key to understanding life on other planets. These organisms rely on bacteria living inside them for survival, and their geological history is believed to be radically different from other forms of life.
Researchers at Queen's University have discovered a 13-million-year cycle in the mountain-building process, which is significantly shorter than previously believed. This finding has implications for our understanding of geological processes that shape the Earth, including the formation of volcanoes and deep-seated continental earthquakes.
Researchers find high levels of 142Nd in terrestrial rocks, contradicting earlier theories on Earth's formation. This discovery suggests that the planet underwent a violent history of collisions and radioactive heat release, leading to its chemical differentiation.
A magnitude 7.2-7.5 earthquake on the Puente Hills fault could result in 3,000-18,000 deaths and up to $250 billion in property damage, according to a study by the USGS and USC. The disaster would be the costliest in U.S. history due to the fault's location under Los Angeles County and adjacent areas.
Researchers discovered minimum melting conditions on early Earth, 200 million years after solar system formation, using a new zircon thermometer technique. This finding provides important information about the first eon of Earth's history and opens up possibilities for life's early foothold.
Roger Bilham warns that Iran is the worst offender, with one in 3,000 Iranians dying in an earthquake since 1900. The professor emphasizes the need for earthquake education to prevent fatalities in developing nations.
Researchers suggest meteorites may have delivered essential elements and asymmetry that led to the development of specific protein and sugar structures on Earth. This theory could provide a plausible explanation for how non-life became ordered and specific chemistry.
Research suggests that planets with high tilt angles may be habitable if they have suitable geography, such as large oceans or continents near the equator. While extreme temperatures would make it difficult for simple life forms to survive, advanced water-dependent life could thrive in these environments.
A new study has found that mobile magma plumes, rather than stationary hotspots, are responsible for the formation of islands and subsurface mountains in the Pacific Ocean. This discovery challenges traditional theories of tectonic movement and sheds light on climate changes recorded in ancient rocks.
A University of Toronto geologist claims that diamonds originated on the ocean floor, supported by a new study published in Nature. The research reveals that diamond formation begins when lava is pushed onto the ocean floor, interacting with sea water to alter its oxygen composition.
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.
Recent claims of fossil life on Earth over 3.8 billion years ago are called into question by researchers from The George Washington University and the Swedish Museum of Natural History. A new study suggests that carbon in ancient rocks may have formed non-biotically, rather than through biological processes.
Scientists at UCLA have developed a new technique that enables them to analyze the molecular composition of ancient fossils, providing conclusive evidence for their biological origin. The study's findings confirm that the oldest known fossils are made of organic matter similar to living microbes.
The total number of living species is uncertain due to uneven taxonomic coverage and statistical barriers. Alroy estimates that one in five currently used species names may be invalid, posing a critical issue for species at risk of extinction.
Scientists have long known that Earth's core is primarily composed of iron, but the cause of seismic waves traveling faster in certain directions was unclear. Recent studies using supercomputer simulations revealed a temperature-dependent alignment of crystal structures in the inner core, shedding new light on this phenomenon.
A research team led by University of Colorado at Boulder Professor Roger Bilham failed to find alternatives to huge Indian earthquakes, concluding that at least one 8.1-8.3 magnitude earthquake and up to seven are overdue due to the movement of the Indian plate towards Tibet.
Researchers at UMass have created a new electron microprobe technique that can date specific parts of rocks with greater precision. This method will provide valuable insights into the movement of tectonic plates and the evolution of rocks over time.
Researchers at Penn State and the University of Miami studied two fault lines in Baja California to understand how strain is partitioned between them. The team found that the Agua Blanco fault has little earthquake activity, while the San Miguel fault has most of the earthquakes.
Great presidents are often stubborn and disagreeable, but also more extraverted, open to experience, and assertive. The study found that nearly all presidents could be classified into one or more of eight presidential types, with some belonging to more than one group.
Rheumatic fever, an immune system disease caused by streptococcal infection, is now believed to have killed Mozart, according to experts. The composer's symptoms and death were consistent with the disease, which was rare at the time due to lack of antibiotics.
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.
A USGS scientist is presenting new evidence that historical tsunamis in the Caribbean were caused by submarine slope failures and landslides on the nearby sea floor. The research suggests that these events triggered long-period waves that approached shallow water near shorelines, resulting in devastating damage.
A new method developed at U of T directly dates individual grains of glaucony minerals, yielding ages scattered over millions of years. The study reveals variable sea levels and provides a way to follow their fluctuations, with applications in oil exploration industry.
Aperlae, a 2,400-year-old Mediterranean port city, was established in the 4th century B.C. to harvest Tyrean purple dye, despite its harsh coastline and lack of fresh water. Archaeological evidence suggests the city's residents used large tanks to manufacture and store the valuable dye.
The $10.3 million, six-year Hawaii Scientific Drilling Program aims to study the formation of volcanoes and the mechanisms within Earth's mantle. Researchers will analyze samples from a 14,500-foot bore hole in Mauna Kea to understand volcanic activity, groundwater movement, and earthquake cycles.