On Monday night, a 7.9 magnitude earthquake struck the Gulf of Alaska. Violent shaking was followed by a tsunami alert, but the seismic ripple that coursed across the Pacific was only eight inches high.

The water in Devil's Hole. Courtesy of U.S. Fish and Wildlife Service

But about 2,000 miles away, in the middle of Death Valley, there was a one foot wave in a small pool of water called Devil's Hole.

The geologic feature is an oblong fissure in the earth, the opening of which is only six feet wide and sixty feet long. Its visible pool is merely a window into a deep aquifer that stretches far into the earth. Its total depth, in fact, remains unknown.

How does a far off quake move a pool of water in the desert thousands of miles away?

"Imagine a big whoopee cushion, and the whoopee cushion is filled with water," said Matthew Weingarten, offering a metaphor for the shape of the Devil's Hole aquifer.

Weingarten is a postdoctoral research fellow at Stanford who studies earthquakes and water interactions. He said that while the aquifer is sizable, its opening is comparatively small, so any sort of seismic disturbance manifests in movement of water at the surface.

"So, if you just push the whoopee cushion just a little bit on its side, the actual pressure changes in the narrow part of the whoopee cushion are very large," he said. "Basically, when you get stresses hitting the deeper part of the aquifer system ... you get these large amplifications of the water level that are representing the geometry of Devil's Hole itself."

The height of the water rises and falls in a sort of flushing motion, as can be seen in this video following a 7.3 magnitude earthquake in Oaxaca, Mexico.

https://www.youtube.com/watch?v=a6h82PIi_-0

"These waves impact a shelf that's a big boulder that fell into Devil's Hole tens of thousands of years ago. It's anywhere from six inches to two and a half feet deep," said Kevin Wilson, aquatic ecologist at Death Valley National Park. "The water runs up and down like if it was a wave of the ocean."

Those disturbances could negatively impact the sensitive ecosystem of the endangered Devil's Hole pupfish.

The Devil's Hole pupfish. Olin Feuerbacher for U.S. Fish and Wildlife Service

The crashing waves create a scouring event which can disturb the fish's food supply and spawning ability. Their eggs can be crushed and small fish can be killed, though this most recent event didn't result in any documented deaths, according to Wilson.

It's not rare for seismic events to cause waves at Devil's Hole. Weingarten documented 219 occasions over a 24 year period. The smallest of which was a Magnitude 3.3 quake in Yucca Valley, 142 miles from the aquifer. It's possible, he said, that Devil's Hole is particularly sensitive to earthquakes coming from the Northwest and Southeast.

Similar seismic waves, or seiches, have been seen in wells in different parts of the world, Weingarten said. But the unique shape of Devil's Hole makes it particularly susceptible.