How Tides Influence Earthquakes

earthquake waves

Here is how tides influence earthquakes along the San Andreas Fault.

Here is how tides influence earthquakes along the San Andreas Fault. Apparently, the tides that alter ocean waves could trigger earthquakes along the San Andreas Fault, in California. Scientists revealed that these types of quakes are highly likely to happen if tides are strengthening, not when they are at the strongest point.

The waves in the ocean and tides are caused by the gravitational pull of the sun and moon, here on Earth. These gravity “tugs” influence not just the sea, but also Earth’s crust. They stretch it and compress it. Previous research concluded that tidal effects on the Earth’s crust might trigger earthquakes.

The team of experts was interested in finding out how the planet’s tides affect small, deep seismic movements known as low-frequency earthquakes. They focused on 81,000 low-frequency earthquakes along the San Andreas Fault, over a period of 7 years. These quakes have a magnitude below one on the Richter scale.

They observed a part of the fault that’s weaker, and it’s easier for it to respond to smaller forces from tides. Tidal strength is variable, over the course of two weeks. The strongest tides occur in spring when the Sun and Moon are aligned. The weakest happen when the sun and moon are not in range.

Scientists were surprised to find out that the number of low-frequency earthquakes did not coincide with the strongest point of the cycle. Instead, they peaked as the tide was strengthening.

This kind of data allows scientists to know when the fault is loaded, and may even help predict when a major earthquake will occur.

The San Andreas fault in Northern California has five major branches, with a total length of approximately 1,250 miles. Experts say that there is an increased chance of a magnitude 6.7 earthquake in the region, over the next 30 years. The San Andreas Fault forms the tectonic border between the Pacific Plate and the North American Plate. This makes it the biggest fault on Earth.

Sadly, behind the palm trees, the sunshine, and Hollywood, California isn’t ready for a massive earthquake striking at some point. Water supplies, infrastructure and electricity and gas pipes are all at risk for a catastrophe if the earth shakes.

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