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New fault in Indian Ocean may trigger earthquakes in future: study

According to scientists, a new plate boundary may be forming on the floor of the Indian Ocean in Wharton Basin as a result of the 2012 earthquake that shook the Andaman-Sumatra region.

The discovery was based on the study of seismic data recorded before, during and after the 2012 quakes and sea floor depth analysis by venturing into the ocean aboard a research vessel.

Key Facts
  • Scientists created a high-resolution imagery of the sea floor by using data which unveiled deformations that had occurred on the tsunamilgIndo-Australian Plate.
  • It showed that the plate had broken along a 1,000 km fracture zone due to 2012 earthquakes, resulting in a new plate boundary and likely to be the site of future fault-slip earthquakes.
  • The analysis showed a new fault system had developed in the area off the coast of Sumatra that was involved in the 2012 earthquakes. The new fault system can trigger more quakes in the future.
  • Slip-strike earthquake occurs when two plates slide horizontally against one another. As a result, earthquake causes deformations that occur in plates distant from fault lines as pressure builds up across a plate.
  • These earthquakes can lead to inter-plate earthquakes and cause a plate to break, resulting in a new boundary and this in turn can lead to even more quakes.
  • This similar scenario is believed to happened in 2012 when two earthquakes struck the Andaman-Sumatran regio (north-west part) of the Indian Ocean which was the largest inter-plate earthquakes ever recorded.

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Scientists witness the birth of an ice cloud for the first time

US based researchers for the first time have observed the creation of ice crystals on individual atmospheric particles in the laboratory.

This observation gives an unprecedented glimpse at most critical but least understood parts of the process of cold clouds formation.

Key Facts
  • Researchers had replicated heterogeneous ice nucleation process in which particle attracts water vapour and forms ice crystals.
  • For this, they replicated suitable conditions found high above Earth’s surface at an altitude of about 6 kilometres where cirrus clouds form in the sky due to ice crystals.
  • They witnessed formation of ice crystals in highly confined climate-controlled chamber in which atmospheric temperature, pressure and humidity conditions were maintained similar in atmosphere.
  • For recreation of ice nucleation, researchers also used extremely small particles of a clay mineral called kaolinite. These particles were just 2–3 microns in size, or less than one-tenth width of a human hair.
  • The kaolinite was then placed in a highly confined climate-controlled chamber of very small size, which was photographed by an environmental scanning electron microscope.
  • It was found that nucleation occurred at temperatures as low as minus 68 degrees Celsius with relative humidity from about 70 to 80%.
Natural process of heterogeneous ice nucleation

At an altitude of about 6 kilometres, relative humidity is high and temperatures are very low. It forces water vapour to collect on any small particles floating in the atmosphere, before freezing in place as an ice deposit. In the atmosphere, such airborne particles could be almost anything, including volcanic ash, aircraft emissions, or even microbes.

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Molten Jet Stream discovered deep inside Earth’s core  

Scientists for the first time have discovered the so-called molten jet stream within the Earth’s molten iron core using latest data obtained from three European satellites called Swarm.

The three satellites were launched in 2013 with the goal of studying Earth’s magnetic field.  The latest satellite data that helps create an sharpest ‘x-ray’ view of the planet.

Key Facts 
  • The molten jet stream is an accelerating band of molten iron circling the North Pole. It just like the jet stream in the atmosphere
  • It moves about 40 km per year, currently in a westward direction. This speed is three times faster than normal outer-core speeds and hundreds of thousands of times faster than rate at which Earth’s tectonic plates move.
  • It is located along a boundary between two different regions in the core. This movement is caused when liquid in core flows toward the boundary from both sides and then is squeezed out sideways.
  • Significance: The satellite data has helped clarify Earth’s inner workings and magnetic field. It showed that changes in the magnetic field are actually being caused by the molten jet stream.
  • The discovery can also add light in changing magnetic field of earth and may relate it with switch in direction of the jet stream.

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