A 10-Kilometer Cliff Time Travel! Discover Earth’s Memories at Choshi’s Byobugaura

I’m Ken Kuwako, your science trainer. Every day is an experiment!

Did you know that Japan has its very own “White Cliffs of Dover”? Located in Choshi City, Chiba Prefecture, Byobugaura is like a massive time capsule where the Earth’s memories are laid bare for all to see. Standing 40 to 50 meters high and stretching for about 10 kilometers along the coast, this magnificent cliffside is a sight you won’t soon forget.

I recently visited this bucket-list destination, and today, I want to share the magic of Byobugaura from a science teacher’s perspective, uncovering the Epic Story of Earth hidden behind this grand scenery.

Byobugaura: Exploring the “Dover of the East”

My journey began at the western edge of Byobugaura. I headed down to the shore near the Iioka Gyobu-misaki Lookout. While this area isn’t a paved promenade, reaching the water’s edge allows you to truly feel the scale of the giant wall towering over you.

When you look closely at the cliff, you can see beautiful, distinct stripes. These are strata—layers of earth. The layers at Byobugaura were formed over millions of years, as sand and mud settled on the ocean floor between 3 million and several tens of thousands of years ago.

Is that a layer of volcanic ash sitting on top?

The reddish-brown layer visible at the very top is likely composed of volcanic ash, such as the Kanto Loam layer. Ash blown from volcanoes like Hakone and Mount Fuji accumulated over an almost unfathomable amount of time to create the ground we stand on today.

Standing my child next to the cliff really puts the scale into perspective. It makes you realize that a human lifetime is just a fleeting moment in the long history of our planet.

Observing Geological Shifts at the Geopark

Next, I moved to the eastern section, which is preserved as the “Choshi Geopark.” Near the Chiba Institute of Science, there is a well-maintained boardwalk where you can observe the strata safely and up close.

Byobugaura is a sea cliff that has been carved away by the fierce waves of the Pacific over eons. It’s said that the cliff used to erode by about one meter every year. Today, it is protected by wave-dissipating blocks, allowing us to admire its form at a more leisurely pace.

While walking along the path, I even spotted what looked like a fault, where the layers had shifted.

While we usually associate “faults” with crustal movements from earthquakes, these particular cracks are thought to be gravity-induced fissures, created by the sheer weight of the sediment or by sliding when the layers were still soft. Witnessing such phenomena is a luxury unique to an outcrop as vast as Byobugaura.

A Bird’s-Eye View: Exploring with Google Earth

After feeling the raw power of the site in person, it’s fun to look at it from a different perspective using technology. I decided to examine the same area via Google Maps and Google Earth.

Source: Google Maps

Source: Google Earth

Source: Google Earth

Seeing the terrain from the sky makes it incredibly clear just how sharply the ocean has bitten into the land to create Byobugaura.

By the way, you can make your virtual exploration even more fun with a few pro-tips. If you are using the browser version or ChromeOS, hold down the Ctrl key while dragging the mouse up or down. This allows you to tilt the camera angle, giving you a 3D view of the cliff face as if you were flying right alongside it!

Here are some handy shortcuts:

Seeing the real landscape with your own eyes, then getting a bird’s-eye view digitally—this movement between the micro and macro is the best way to develop a “scientific eye.”

I highly recommend visiting Byobugaura on a clear day. A story millions of years in the making is waiting right beneath your feet.

https://phys-edu.net/wp/?p=41688

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