Nearly everyone in the US depends on food crops grown in California, so farmers must continue to pull what little water remains in underground aquifers. This is causing the state to actually sink. It's been sinking for decades, but the problem is getting worse. Reveal News writes, "Last summer, scientists recorded the worst sinking in at least 50 years. This summer, all-time records are expected across the state as thousands of miles of land in the Central Valley and elsewhere sink."
As a result, the "sinking is starting to destroy bridges, crack irrigation canals and twist highways across the state, according to the U.S. Geological Survey."
Joseph Poland of the U.S. Geological Survey used a utility pole to document where a farmer would have been standing in 1925, 1955 and where Poland was then standing in 1977 after land in the San Joaquin Valley had sunk nearly 30 feet. Credit: U.S. Geological Survey
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Later this month, scientists will set explosive charges on Mount St Helens as part of an effort to study the seismic geology of the Pacific Northwest. Read the rest
The Darvaza gas crater, known to locals as "Door to Hell" or "Gates of Hell" is located in the Karakum Desert of central Turkmenistan (about 150 miles from the nation's capital). Read the rest
Opals, a rainbow of fire locked in rock, are among the most wonderful of nature's gifts. Maggie Koerth-Baker
returns with the light truth about weird silica.
Behold the splendid "Earth Cake" baked and decorated by Redditor Clatence. "The cake is a mixture of chocolate and red velvet cake mixes," Clatence explains. The core is raspberry jam. Nicely done!
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Sometimes before an earthquake, strange bright orbs and glows are seen in the sky, like the scene visible in this video clip captured a half hour before the 2008 quake in Sichuan, China. You might think these are related to the UFOs that cause the quakes, but new research not only suggests a natural cause but also raises the possibility that the phenomena could be an indicator that a quake is coming. The scientists from Quebec Ministry of Natural Resources and San Jose State University suggest that rocks under high stress deep underground release oxygen ions that eventually make their way to the surface, ionizing air pockets above ground and creating a light-emitting plasma.
“If you see visible lights in the sky, and you live in an earthquake-prone area, they might be an early-warning sign that an earthquake is approaching,” geologist Robert Thériault says.
More in Smithsonian: "Why Do Lights Sometimes Appear in the Sky During An Earthquake?" Read the rest
Image: Tom Pfeiffer/Volcano Discovery
Sicily's Mount Etna volcano is currently erupting. The series of explosions began on October 26, but on November 11, the mountain did something rare and nifty. Over the course of several hours it blew out dozens of perfect smoke rings, each hundreds of feet in diameter, including the one pictured here.
It's not the first time Etna has done this. Nobody knows exactly how the rings form, but people have been photographing smoke rings coming from Etna since at least 1970. Volcanologist and tour guide Tom Pfeiffer took this picture, as well as several others that you can see at his Volcano Discovery website. He suspects that the smoke rings are formed when eruptions alter the shape of volcanic vents. Read the rest
Today at i09, geophysicist John Bellini will be answering your earthquake-related questions
, starting at 12:30 Pacific time. Read the rest
This image shows magnetic anomalies in the South Pacific — underwater lines where the crust of the Earth either matches up with the planet's overall magnetic polarity (reds and purples) or is completely reversed (blues). Invisible to the naked eye, these stripes run along all of Earth's ocean basins. We first noticed them in the 1950s and, at first, they were a giant mystery. Why would there be these distinct lines of magnetism, and why would the lines fluctuate in their polarity? As Chris Rowan explains at the Highly Allochthonous blog, the answer ended up being a key part of proving that chunks of the Earth's crust were moving away from each other.
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Fred Vine and Drummond Matthews thought through the consequences of the hypothesis put forward by Harry Hess, that new oceanic crust was being continuously produced by the eruption of basalt at mid-ocean ridges. When combined with the facts that newly cooled basalt has a strong remanent magnetisation aligned with the ambient magnetic field, and that the Earth’s magnetic field reverses its polarity every million years or so. Vine and Matthews* argued that if seafloor spreading was indeed occurring at mid-ocean ridges, then linear positive and negative magnetic anomalies, formed from crust produced in normal and reversed polarity chrons, would form a symmetric pattern around the mid-ocean ridges, which is exactly what we see.
Scientists using radio waves to estimate the thickness of the ice sheet that covers Greenland found a canyon
— more than 2600 feet deep and almost 500 miles long — buried under the ice. Longer than the Grand Canyon, the Greenland canyon hasn't ever been seen by humans. It was probably last completely uncovered 4 million years ago. Read the rest
Geology blogger Dana Hunter is putting together some resources that will allow you to take yourself on a fantastic tour of America's most famous volcano
. Includes maps, suggested background reading, and routes that will ensure you get to see the most interesting spots on the mountain — and learn stuff while doing it! Read the rest
A week ago, Randall Munroe finished "Time", XKCD's long, running, slow-updating, 3,000+ frame comic telling the story of two people who discover an impending superflood that would destroy their society. Randall's explained in detail what was going on there, from the geology of the thing (it's set millennia in the future, amid a civilization denied the ability to jumpstart itself by the paucity of remaining fossil fuels, and the flood is modelled on a real event that sealed off the Mediterranean Sea five million years ago) to the fictional language the upland culture speaks (designed by a linguist, and still mysterious).
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A slope may look stable, but that doesn't mean it will always be
stable. The same geologic material can, under certain circumstances, lose its strength and integrity. Here, a geologist demonstrates how this might happen with the help of a tired kitteh
. Read the rest
In the 1870s, a French geographer proposed digging a canal from the Mediterranean to flood a low-lying part of the Sahara Desert
. He pitched it as good for business and good for local environments, writes Ron Miller at i09. But I can't help but think of Plagues and Pleasures of the Salton Sea
— a documentary about the development, culture, and slow, ongoing destruction of a salty, inland sea
that accidentally formed in southern California in the first part of the 20th century. Read the rest
Mars' landscape was formed by flowing water, and the proof is in the pebbles
. [BBC] Read the rest