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New technology hopes to predict bluff failures before they happen

(KGTV) – For years, researchers have studied the California coast, observing cliff erosion and how it has changed over the years.

You may remember back in August 2019, a beach cliff in Encinitas fell on beach goers, killing three of them. One year later, part of the same bluff also collapsed.

Because of incidents like these, Scripps Oceanography researchers have spent years studying cliff erosion. But over the past month they’ve been experimenting with new technologies. In addition to expanding their coverage area, they hope to be able to predict when a cliff will fall before it does.

“You can see a rock wall that looks like solid rock, but it will just fall over,” research geophysicist Mark Zumberge shares with Scripps Oceanography. He is the latest addition to a research team led by. is directed Adam Young, a marine geologist whose research specializes in cliff erosion.

Zumberge shares that Young uses a tool called lidar that uses a laser to scan the wall of a cliff, which in turn creates detailed images and allows viewers to see how much material has come out. Zumberge says data was used to create a database of how fast the cliffs were eroding and where.

Two other members of the team are studying the deformation of the earth’s crust. According to Zumberge, the two use sensors and GPS to study the stress on the Earth’s tectonic plates as they move. This data enables researchers to get an idea of when and where earthquakes occur.

But when Zumberge joined the team a month ago, he presented a new piece of their tooling puzzle – fiber optic strain sensors.

“We stretch it in a borehole,” explains Zumberge, while holding a piece of glass fiber in his hands, “and essentially measure the change in length in this glass fiber when the ground moves.”

The tool generates 200 data samples per second while measuring the smallest movement. It produces data in real time unlike the other tools that can take weeks, months or even years.

The fiber optic strain sensor sends a laser light into the fiber optics, the electronics then analyze the light and detect any change in the height of the cable, which can be as little as nanometers. This change in elevation of the rope or any movement of the rope corresponds to any movement within the cliff that could be caused by either rain or groundwater.

Zumberge says it can find essentially any signal that a bluff is slowly breaking down.

In the laboratory where the technologies are assembled, Zumberge reflects on the most recent cliff failures like the one in 2019: “It is clearly something of social relevance, people have lost their lives.”

However, the new tool does not yet examine our California cliffs.

The team is waiting for that Adoption of the AB-66 draft law that seeks to speed up sciences like the tool Zumberge is working on and create a potential alert system. Zumberge says while they are not the first group to attack this issue, he hopes they will be able to produce the most accurate data possible.

“Hundreds of miles of California coastline and cliffs,” says Zumberge, “and it would be great to have a better understanding of how to identify the riskiest places.”

When the law passes, the team hopes to monitor two areas of fiber and possibly other technologies that the team is already working with. The first would be along the cliffs in Del Mar.

The second location would be Beacon Estate Beach in Encinitas. “There is an access point to the beach that was built on an old landslide,” describes Zumberge, “and we want to find out how it moves. Does it creep all the time? Will it stay still for a while, will it move? “

Those are where they want to start, but Zumberge says these tools could be used for other things in the future, such as: B. to see if they can possibly track earthquakes or warn others of tsunamis.

These are just a few of the many questions that I hope you will soon answer. Zumberge shares the reality for most people who visit California coasts: “People don’t always listen to warnings, as we’ve seen.”

When asked if he believed his technology would one day be that warning to others, he said, “Yes, we hope. We’ll see.”

The bill is waiting to be negotiated by a committee on August 16. If you pass, your work will be funded for three years from January 1st, 2022.

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