September 14, 2016: Researchers at the University of Tokyo say large quakes are more likely during high tides, which happen twice a day. During high tides, the oceans are pulled by the moon’s gravity, but during a full and new moon, twice a month, the tides are particularly high, especially when the moon, the sun, and Earth line up.
Full moons may cause bigger earthquakes, according to a new study. This, researchers say, can further stress geological faults, triggering earthquakes.
“The probability of a tiny rock failure expanding to a gigantic rupture increases with increasing tidal stress levels,” the researchers wrote in an article that appeared in the British journal Nature Geoscience.
While the theory is not new, the study is the first to find a statistical link between the moon and earthquakes.
For example, the researchers found that the 2004 Sumatra quake as well as a major 2011 quake in Japan both happened during high tides. The researchers say nine of the 12 biggest quakes ever recorded were timed with full or new moons.
The findings could help with earthquake forecasting, especially in places like Japan where earthquakes are common.
Bengaluru, October 16, 2017 : Continuous monitoring of water levels in the foothills of the Himalayas can warn about an impending earthquake in the region, which is due for a major temblor.
This recommendation to the Ministry of Earth Sciences has come from Ramesh Singh, professor of environmental sciences at California’s Chapman University, who is also president of the Natural Hazards Group of the American Geological Union.
Singh says the utility of monitoring the water levels of underground aquifers for predicting earthquakes in quake-prone regions has been confirmed from analysis of water level data in a bore hole collected during the earthquake that rocked Nepal’s Gorkha district on April 25, 2015.
The findings of the study carried out by Singh and three seismologists from China have recently been published in the journal Techtonophysics.
The Gorkha quake, one of the deadliest in Nepal, killed about 5,000 people mainly in Nepal, a few in bordering India, two in Bangladesh and one in China, and injured about 9,200 people.
Whenever earthquakes occur, widespread cracks and deformations on the earth’s surface are common, resulting in changes in groundwater levels, Singh told this correspondent in an email.
In China, many parameters are being monitored in water wells, including water level, water temperature, and water radon concentrations to detect any signal prior to an impending earthquake.
According to the scientists, due to seismic wave propagation, the volume of an aquifer expands and contracts, forming fractures that change the water flow in a bore well sunk into the aquifer.
In the case of the Gorkha quake, the scientists considered the water level in a bore well — called “Jingle” well — atop an aquifer in China’s Shanxi province, 2,769 kilometres from the temblor’s epicenter. The data was analysed soon after the Nepal earthquake.
A “spectrum analysis” of the co-seismic response of the bore hole water level showed large amplitude oscillations with a maximum peak-to-peak value of about 1.75 metres associated with ground vibrations generated by the earthquake, says their report.
In addition, the analysis revealed the arrival of a possible precursor wave at the “Jingle” well about 6.5 hours prior to the actual occurrence.
“The study of co-seismic changes in groundwater has emerged as an important research area which can provide an improved understanding of earthquake processes and corresponding changes in surface and subsurface parameters,” Singh said.
Water level data in close proximity to the epicenter may be of great importance in getting early warning signals of an impending earthquake, he said. China and the United States routinely monitor aquifer water levels at 15-minute intervals.
In the light of the finding, Singh said that “India’s Ministry of Earth Sciences may consider deploying water level sensors in the Himalayan foothills areas, which may provide valuable information about an impending earthquake in the Himalayan region, which is due for a major earthquake.”
Such data, he added, “is also useful in understanding the dynamic nature of the Indian plate”.
However Arun Bapat, former head of Earthquake Engineering Research at the Central Water and Power Research Station in Pune, says he has some reservations about the study’s conclusion that water level changes observed in the bore hole were the warning signal for the Gorkha earthquake.
“Various effects associated with a large earthquake (Magnitude 7.5 or more) such as electrical, magnetic, geological, tectonic, hydraulic, radioactivity, etc., have been observed within about 600 to 800 km from the epicenter (but not beyond),” Bapat told IANS.
Bapat said the magnitude of the Gorkha quake was about 6.5 to 6.75 which is considered as moderate. “The effect of this quake on water level changes at a distance of 2,769 kilometres from its epicenter is almost not possible.” (IANS)
The science communities since a long time have been debating upon the existence of Planet Nine.
Space highlights different shreds of evidence based on which scientists are stating the claim.
What Is Planet Nine?
Planet Nine is a hypothetical planet present in the far outer Solar System, whose mass is estimated to be 10 times more than the mass of Earth. The planet is said to be 20 times farther than the sun than Neptune is.
What Do Researchers Have To Say?
Dr Konstantin Batygin, a planetary astrophysicist at the California Institute of Technology, said that there were five different lines of observational evidence which pointed to the existence of Planet Nine. He stated that if this theory does not sound believable, then people would have to come up with the answers of the five pieces of evidence which could lead to further confusion.
Batygin in 2016 published a study examining the six known objects in the Kuiper Belt, a circumstellar disc in the Solar System beyond the planets that extends from the orbit of Neptune towards interstellar space.
The study examines all the objects have elliptical orbits pointing in the same direction and are tilted the same way. These serve as evidence to the planet’s existence.
It is being said that the objects are tilted 30 degrees downward compared to the plane where the eight official planets circle the sun. Researchers also made use of computer simulations of the solar system including the Planet Nine and to demonstrate that there should be more objects tilted a whopping 90 degrees to solar plane. It was revealed that five such objects, which fit these parameters were already known.
The study led to the birth of two more ideas. Researchers said that this planet could have tilted the planets of the solar system during the last 4.5 billion years.
Planet Nine’s existence could also tell the reason as to why Kuiper Belt objects orbit in the opposite direction as compared to other things in the solar system.
London, Sep 28: The violent and chaotic process that led to the formation of Earth resulted in the loss of more than 40 per cent of its mass, says a study.
Analysing a mixture of earth samples and meteorites, the scientists shed new light on the sequence of events that led to the creation of our home planet.
Planets grow by a process of accretion – a gradual accumulation of additional material – in which they collisionally combine with their neighbours.
This is often a chaotic process and material gets lost as well as gained, said the study published in the journal Nature.
Massive planetary bodies impacting at several kilometres per second can generate substantial heat which, in turn, produces magma oceans and temporary atmospheres of vaporised rock.
Repeated loss of this vapour envelope during continued collisional growth causes the planet’s composition to change substantially.
“We have provided evidence that such a sequence of events occurred in the formation of the Earth and Mars, using high precision measurements of their magnesium isotope compositions,” said lead researcher Remco Hin from University of Bristol in Britain.
“Magnesium isotope ratios change as a result of silicate vapour loss, which preferentially contains the lighter isotopes. In this way, we estimated that more than 40 per cent of the Earth’s mass was lost during its construction,” he said.
For the study, the researchers analysed samples of the Earth together with meteorites from Mars and the asteroid Vesta, using a new technique to get higher quality measurements of magnesium isotope ratios than previously obtained.
“We now show that vapour loss during the high energy collisions of planetary accretion has a profound effect on a planet’s composition,” Hin said.
“This process seems common to planet building in general, not just for Earth and Mars, but for all planets in our Solar System and probably beyond, but differences in the collision histories of planets will create a diversity in their compositions,” he added. (IANS)