A big sideways slip on Mars

Mars Reconnaissance Orbiter today released an image of a really spectacular transform fault on Mars, a spot where the ground cracked and two sections moved sideways to each other. In this case, the sideways movement was about 300 feet. The image is posted below the fold.

Compare that with the Japanese magnitude 9 earthquake on March 11, which only shifted the seabed sideways 165 feet while raising it 33 feet. The quake that moved these two pieces of Martian bedrock sideways must have been quite a ride.
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The trial of seven Italian earthquake experts facing manslaughter charges for not correctly predicting an earthquake continued this week.

The trial of seven Italian earthquake experts facing manslaughter charges for not correctly predicting a deadly earthquake continued this week.

The prosecution’s argument that the experts had underplayed the possible occurrence of a major quake was bolstered by testimony from Daniela Stati, the former civil protection officer for Abruzzo, who took an active role in the March 31 meeting. Stati confirmed what she had previously told prosecutors in 2010, that one of the indicted said during the meeting that the continuing tremors represented a “favorable signal” because there was a continuous discharge of energy that made stronger tremors less likely. In fact, scientific evidence suggests that groups of small earthquakes tend instead to increase the chances of a major earthquake nearby, even though the absolute probability of such a quake remains low. Stati said that nobody within the commission objected to this statement. She also underlined that the “reassuring message” given to the press by her, L’Aquila Mayor Massimo Cialente, and two of the indicted, Franco Barberi and Bernardo De Bernardinis, was based on comments made at the meeting.

On the way to its winter haven, Opportunity found more evidence of water on Mars

On the way to its winter haven, Opportunity found more evidence of liquid water that once flowed on Mars, specifically a geological vein that they think might be gypsum.

The vein examined most closely by Opportunity is about the width of a human thumb (0.4 to 0.8 inch, or 1 to 2 centimeters), 16 to 20 inches (40 to 50 centimeters) long, and protrudes slightly higher than the bedrock on either side of it. Observations by the durable rover reveal this vein and others like it within an apron surrounding a segment of the rim of Endeavour Crater. None like it were seen in the 20 miles (33 kilometers) of crater-pocked plains that Opportunity explored for 90 months before it reached Endeavour, nor in the higher ground of the rim.

According to what project scientist Steve Squyres said at a press conference today at the AGU meeting, “This is the single most significant piece of evidence that liquid water once flowed on Mars.”

The explosive Kilauea volcano

At a press conference just completed at the American Geophysical Union meeting in San Francisco, geologist Don Swanson of the U.S. Geological Hawaiian Volcano Observatory revealed that the Kilauea volcano on the Big Island of Hawaii has been in an explosive mode about sixty percent of the time in the past 2500 years. “Kilauea is not the gentle volcano that most people assume,” noted Swanson.
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Colorful Vesta

False color of Vesta

Tonight’s press conference at the American Geophysical Union conference focused on the latest results from Dawn, orbiting the giant asteroid Vesta. Or to put it as scientist Vishnu Reddy put it, “Vesta is the most colorful asteroid in the solar system.”

At least, in geological terms. To our human eye the asteroid wouldn’t be so spectacular. However, the false color images released by the scientists show the global geological diversity of Vesta. From the press release:
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Mountains and buried ice on Mars

Mountains and buried ice on Mars.

New images from the high-resolution stereo camera on ESA’s Mars Express orbiter allow a closer inspection [of the Phlegra Montes mountain range] and show that almost every mountain is surrounded by ‘lobate debris aprons’ – curved features typically observed around plateaus and mountains at these latitudes. Previous studies have shown that this material appears to have moved down the mountain slopes over time, and looks similar to the debris found covering glaciers here on Earth.

Chile’s powerful Cerro Hudson volcano is threatening to erupt

Chile’s powerful Cerro Hudson volcano has come back to life and is threatening a major eruption.

Patagonians are worried. Many remember Mount Hudson’s catastrophic eruptions of 1971 and 1991. The latter eruption was one of the most violent registered eruptions in Chile, and lasted for five months. At its peak it turned day into night, making the banks of nearby Huemules, Cupquelan and Ibáñez Rivers collapse with ash. Many areas in the region are still covered with ash, pumice and other volcanic rocks. “These are the characteristics of this highly explosive volcano,” said Juan Cayupi, a volcanologist at the National Emergency Office.

Catching an avalanche on Mars, as it happens

The Mars Reconnaissance Orbiter team today released this really cool image from Mars, showing an avalanche near the North Pole, in progress. The image looks directly down the cliff face from above. At the base of the cliff we can see the dust cloud from the crash of material billowing out away from the scarp.

What impresses me most about this image is that it was taken by an orbiting spacecraft approximately 200 miles above the planet’s surface, moving at thousands of miles an hour. Yet, the camera not only had the resolution to see the cloud of dust, it could snap the image fast enough to capture the actual fall of material (the white wisps down the side of the cliff that are reminiscent of a waterfall).

Also intriguing is the visible steep face of the cliff face itself. I know a lot of rock climbers who would love to literally get their hands (and chocks) on that rock face. And in Mars’s one-third gravity, rock climbing would surely be different.

avalanche on Mars

The strange rubbing boulders of Chile

The strange rubbing boulders of Chile.

Then, on another trip to the Atacama, Quade was standing on one of these boulders, pondering their histories when a 5.3 magnitude earthquake struck. The whole landscape started moving and the sound of the grinding of rocks was loud and clear.

“It was this tremendous sound, like the chattering of thousands of little hammers,” Quade said. He’d probably have made a lot more observations about the minute-long event, except he was a bit preoccupied by the boulder he was standing on, which he had to ride like a surfboard. “The one I was on rolled like a top and bounced off another boulder. I was afraid I would fall off and get crushed.”

The abstract is here.

Rough Terrain

The Dawn scientists have released another spectacular image of the south polar mountain on Vesta whose relative size is three times that of Mount Everest. More information about the image can be found here. From the caption:

The peak of Vesta’s south pole mountain, seen in the center of the image, rises about 13 miles (22 kilometers) above the average height of the surrounding terrain. Another impressive structure is a large scarp, a cliff with a steep slope, on the right side of this image. The scarp bounds part of the south polar depression, and the Dawn team’s scientists believe features around its base are probably the result of landslides.

Mountain on Vesta

It appears the light gravity on Vesta allows for the formation of extreme topology.

Exploring an abandoned mine in Nevada

An evening pause: From the youtube webpage:

This inclined shaft is located outside of Searchlight, NV. The shaft itself is about 350 feet deep with two extensive drift levels along its length. We found a winze [a vertical shaft] in the lowest drift level that went down to what appeared to be an additional level.

I must emphasize that mines are very dangerous, and should be approached with great care and caution. Unlike a cave, which has had eons to slowly establish its stable structure, a mine is cut into the rock instantly (compared to geological time), and is thus very unstable and prone to collapse.

The rover Opportunity as seen from Mars orbit

Opportunity on Endeavour Crater rim

The image to the right was taken by Mars Reconnaissance Orbiter, with the white arrow showing the Mars rover Opportunity perched on the rim of Endeavour Crater.

The rover’s scientists hope that the rocks found on the crater rim, dredged up from deep below when the crater impact occurred, will be the oldest rocks so far touched on the Martian surface, and thus give them a peek at ancient Martian geology.

Farmers flee as Indonesia’s Mount Tambora volcano rumbles

Farmers begin fleeing as Indonesia’s Mount Tambora volcano comes back alive.

Villagers like Hasanuddin Sanusi have heard since they were young how the mountain they call home once blew apart in the largest eruption ever recorded — an 1815 event widely forgotten outside their region — killing 90,000 people and blackening skies on the other side of the globe. . . . The April 1815 eruption of Tambora left a crater 7 miles (11 kilometers) wide and half a mile (1 kilometer) deep, spewing an estimated 400 million tons of sulfuric gases into the atmosphere and leading to “the year without summer” in the U.S. and Europe.

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