The island of Canada that remained safe despite two thousand earthquakes

 

 

The island of Canada that remained safe despite two thousand earthquakes

2,000 earthquakes in a single day in early March.

About 240 kilometers off the coast of Vancouver Island is Endeavor, where hundreds of earthquakes were felt in a single day on March 6.

The depth of these earthquake shocks was five kilometers from the ground. Usually, such earthquakes can cause destruction in coastal areas, but the magnitude of these earthquakes in Vancouver Island was less than one on the Richter scale.

Zoe Krauss, who has a PhD in geophysics from the University of Washington, is studying land and subsea change data in the Endeavor area of Vancouver Island for her research.

"Mediterranean rocks are not really capable of producing high-magnitude earthquakes," she says.

He adds that some excavations around the coast have revealed that these tremors are not a cause for concern but rather geological processes in the deep sea that are creating a new seabed in the area.

These earthquake shocks are not dangerous for people. They are overall minor shocks and due to them the vibrations on the earth's surface have been confined to a small area.

What is the reason for so many earthquakes?

Endeavor is located on a cliff in the middle of the ocean on Vancouver Island.

The Earth's surface is divided into seven major and eight minor plates. The largest plates are the Antarctic, Eurasian and North American plates.

These plates are layers up to 125 km thick beneath Earth's average mountain ranges. A seamount is formed under the ocean when two subterranean plates move away from each other.

Now, as the earth's plates move apart, large-scale volcanic eruptions begin, and when the volcano cools, rocks are formed, which are called 'mid-ocean ridges'. Thus a new layer is formed inside the ocean.

Endeavor is located on the Pacific and Juan de Fossa plates, says Zoe Krause. Aftershocks at Endeavor indicate that the ocean floor is spreading.

As these plates spread, they spread about 3.3 feet (one meter) before reaching a critical point. This stretching of the earth causes pressure in the earth, due to which a new layer is formed under the sea and this pressure also causes earthquakes.Recent earthquakes show that the sea floor beneath Endeavor is stretched to its maximum extent.

According to Zoe Krause, the most likely possibility now is that magma (hot lava) from the volcano will now fill the void and dry out there, adding a new layer to the ocean floor.

How dangerous is this earthquake?

Endeavor land is the area under which the ocean floor is forming.

Zoe Krause told Live Science that rocks formed in the mid-ocean aren't actually capable of producing earthquakes larger than magnitude 5. However, due to this, there will not be much erosion of the underwater land.

Earthquakes are an interesting process scientifically, Krause said, because they can reveal details about how the ocean floor separates and how new Earth's crust forms. At Endeavor, the Pacific plate and the Juan de Fossa plate are separating.

This process creates fault lines there and thins the Earth's crust, enabling volcanic lava to erupt.

When this lava reaches the pre-existing surface of the ocean floor, it cools and hardens, forming new oceanic crust.

Endeavor's location on Vancouver Island is continuously monitored by the Canada Oceans Networks organization. Zoe Krause says the region has become more seismically active since 2018.

However, on March 6, at least 200 small earthquakes shook the ocean floor here every hour. Researchers found that a total of 1,850 earthquakes were recorded here that day.

How is the research team monitoring this earthquake?

After March 6, earthquake aftershocks have decreased slightly, says Zoe Krause. Krause is closely monitoring earthquakes here.

He said that the most probable cause of the earthquake is that the sea floor has spread to its maximum extent and this has created a lot of pressure and hence the earthquake.

Krause says such earthquakes occur regularly, about 20 years apart. The last time such earthquakes occurred in this area of Endeavor was in 2005.

Continuous monitoring of the Endeavor site began in 2011, so the monitoring team does not have data from previous earthquakes. But they also have many questions about the source of the lava that will eventually form the new Earth's crust.

Many questions still remain to be answered, Krause says, such as 'how does the Earth's crust form, why do these events occur, and what causes lava to erupt?'

But for now, he and his team are watching to see what happens in the coming days.