https://www.eurekalert.org/news-releases/991750
INTRO: Researchers from the University of Cambridge and the Dublin Institute for Advanced Studies have discovered that variations in the thickness of tectonic plates relate directly to the distribution of earthquakes in Britain, Ireland and around the world.
The study also solves an enduring mystery as to why small earthquakes happen frequently in Britain but are almost completely absent from neighbouring Ireland.
The researchers produced a computer-generated image of Earth’s interior using a technique called seismic tomography, which works in a similar way to a medical CT scan. The data they collected revealed variations in the thickness of the solid outer part of Earth, also known as the lithosphere, across Ireland and Britain.
“Earthquake locations are surprisingly uneven across Britain and Ireland,” said Sergei Lebedev, lead author of the research Cambridge’s Department of Earth Sciences. “We can now explain this disparity, which has puzzled scientists for over a century.”
The researchers found that the lithosphere is thin and weak beneath western Britain, meaning that the rocks can bend easily — triggering earthquakes across this region. In contrast, Ireland sits on top of thick and strong lithosphere, explaining the lack of earthquakes.
Even though the UK is located far from the nearest plate boundary, where most earthquakes happen across the world, minor tremors still a relatively common occurrence. According to the BGS, the UK is rattled by between 200 and 300 small to moderately-sized tremors every year, mostly occurring along the western side of mainland Britain. Less than 30 out of these earthquakes are strong enough to be felt, although on rare occasions they can cause more damage... (MORE - details)
PAPER: http://dx.doi.org/10.1093/gji/ggad194
INTRO: Researchers from the University of Cambridge and the Dublin Institute for Advanced Studies have discovered that variations in the thickness of tectonic plates relate directly to the distribution of earthquakes in Britain, Ireland and around the world.
The study also solves an enduring mystery as to why small earthquakes happen frequently in Britain but are almost completely absent from neighbouring Ireland.
The researchers produced a computer-generated image of Earth’s interior using a technique called seismic tomography, which works in a similar way to a medical CT scan. The data they collected revealed variations in the thickness of the solid outer part of Earth, also known as the lithosphere, across Ireland and Britain.
“Earthquake locations are surprisingly uneven across Britain and Ireland,” said Sergei Lebedev, lead author of the research Cambridge’s Department of Earth Sciences. “We can now explain this disparity, which has puzzled scientists for over a century.”
The researchers found that the lithosphere is thin and weak beneath western Britain, meaning that the rocks can bend easily — triggering earthquakes across this region. In contrast, Ireland sits on top of thick and strong lithosphere, explaining the lack of earthquakes.
Even though the UK is located far from the nearest plate boundary, where most earthquakes happen across the world, minor tremors still a relatively common occurrence. According to the BGS, the UK is rattled by between 200 and 300 small to moderately-sized tremors every year, mostly occurring along the western side of mainland Britain. Less than 30 out of these earthquakes are strong enough to be felt, although on rare occasions they can cause more damage... (MORE - details)
PAPER: http://dx.doi.org/10.1093/gji/ggad194