Posts

September 19, 2014

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10:25 PM | Erosion Rate And Previous Extent Of Interior Layered Deposits On Mars Revealed By Obstructed Landslides
Landslides on Mars typically have runout distances much larger than equivalent features on Earth, and therefore can interact with older landforms that are distal to the failure scarp. Regardless of the exact formation mechanism of these landslides, it is evident that their combined large area and relatively well constrained formation age can be exploited to better understand the evolution of coincident features, particularly if those features have been modified since the landslide event. […]
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5:19 PM | Geo 730: September 19, Day 627: Faulty Cove
In this overview of the cove on the north side of Yaquina Head, we can see the fault-mediated cave on the west side, the smaller fault-mediated cave on the east, and we can see that these faults are essentially parallel to each other. This suggests that the cove itself is the result of a broad fault zone creating a weak brecciated area between the two walls, where wave action has managed to erode out the broken rock. Though a casual tourist is not in a position to do so, what further […]
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2:35 PM | Pulling secrets from deep-sea, drillbit-eating rocks
Amy West is the science writer and outreach and education officer for the JOIDES Resolution, a drill ship operated by the International Ocean Discovery Program (IODP) that is on a two-month expedition studying the Izu-Bonin-Mariana Arc in the region where the Pacific Plate is descending under the Philippine Plate to form the Mariana Trench and the deepest point in the ocean–the Challenger Deep. This is her latest blog post about the expedition.
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1:57 PM | Going on a rock cruise
A trio of two-month expeditions in 2014 will be in the region where the Pacific Plate is descending under the Philippine Plate to form the Mariana Trench and the deepest point in the ocean–the Challenger Deep. Scientists will get under the skin of the Izu-Bonin-Mariana Arc, which stretches nearly the distance from Los Angeles to Chicago

September 18, 2014

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7:28 PM | USGS Releases a New Mapping Tool to Assist Tsunami Shelter Development
It may happen just once in your lifetime: a large tsunami is coming, big enough to make you run for your life. Where do you go? USGS has released a new tool to help planners plot out shelters in West Coast communities and other tsunami-hazard zones.
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6:24 PM | Geo 730: September 18, Day 626: Faulty Sea Cave 2
Looking at the other, western, side of this cove reveals another, smaller, sea cave. But like yesterday's example, it's clearly associated with a vertical fracture, almost certainly a fault. The reason I don't simply assert that it is a fault is that I would need to demonstrate some evidence of offset parallel to the fracture, such as displaced layers, broken clasts, slickensides, or something along those lines. Obviously, I couldn't get close enough to do that, so I have to leave open the […]
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5:00 AM | The Other Ice-Age Flood: Bonneville Flood
The highway through Lewiston, Idaho passes by a gravel cut slope with a retaining wall at its base to catch material that ravels off the slope. The cut slope is a deposit from an ice-age flood. But this flood was not derived from the rapid draining of ice-age glacial Lake Missoula. Instead this thick deposit of gravel was derived from a massive ice age flood when Lake Bonneville in northern Utah overflowed into the Snake River drainage in southern Idaho approximately […]

September 17, 2014

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10:30 PM | More Evidence That Early Earth Was Not A Complete Hellhole
The popular image of the early Earth as a magma-drenched ball of despair has taken yet another blow. New research affirms that our planet's first 500 million years were at times surprisingly similar to the present day — including the presence of oceans, continents, and crustal plates. Read more...
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7:15 PM | Geo 730: September 17, Day 625: Faulty Sea Cave
Looking down into the same cove we saw from a bit farther back yesterday, the west (left) wall is improbably flat and straight. This is almost certainly a fault surface. It could possibly be a joint, but the jointing here is extremely irregular, and such an extensive one along a consistent plane seems unlikely. Above the sea cave in the middle left f the photo, we can see two vertical fractures which apparently form the boundary of that cave; from that we can see they're roughly parallel. I'll […]
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12:34 PM | Pulling Secrets from Deep-sea, Drillbit-Eating Rocks
Hidden seafloor can harbor tales of volcanic explosions. But getting it to cough up some stories can lead to a butchered drill bit.
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12:00 PM | The Wealth Under Afghanistan
Credit: Image of map courtesy of the USGS and composite image by Patricia WaldronBy: Patricia Waldron, Inside Science(Inside Science) -- People living in Afghanistan have mined precious gems from their land, such as lapis lazuli, since the times of the Egyptian pharaohs. But modern analyses of the country's mineral deposits show that the Afghan people have barely scratched the surface of their mineable wealth. read more

September 16, 2014

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8:14 PM | The Matter of Habit, Cleavage, and Fracture in Minerals
This is a confusing one for students. It can sometimes be a challenge for folks who already have their PhD’s in geology. How do you distinguish among crystal habit, cleavage, and fracture in minerals? I talk a bit about cleavage … Continue reading →
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7:50 PM | Geo 730: September 16, Day 624: Yaquina Head, Redux
Back in July, Dana and her friend B. made a whirlwind visit, and we headed over to the coast for cooler weather. Many of the spots on this trip were ones I've covered before in the Geo series, but the photos are different. In particular, looking through the folder, this trip happened to be at near high tide, so there are some distinct differences, emphasizing the importance of considering tidal variations when planning coastal geology trips. Here, we're looking north from Yaquina Head, over a […]
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7:26 PM | Grande Ronde Basalts at the Grand Ronde
The southeast corner of Washington State provides an opportunity to see the source area of some of the great flood basalt flows that cover much of eastern Washington. While there are plenty of impressive basalt cliffs and canyons in Washington State, the canyon land topography of the Hells Canyon and Grande Ronde River Canyons as well as tributaries gives an even better impression of  thickness of the basalt flows.View down Rattlesnake Creek to the Grande Ronde River.Basalt lined slopes of […]
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3:50 PM | Cool! 3D Printing In The Geosciences
Geological  Fabrication Laboratory!.. Yes.. the future is already here.and it is run by Franciszek Hasiuk of Iowa State University. He explains in a short note in GSA Today just why 3 dimensional  printing is so useful especially in the geosciences:In the geosciences, we struggle with a fundamental problem—we love nature, but its aspects can be truly enormous or fantastically miniscule, very far away or exceedingly rare. Our burden is to overcome these conditions and communicate […]
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2:00 PM | Fossil Burrows Shed Light on Great Plains' Roots
The Great Plains didn't evolve in a vacuum. Ancient rodents helped shape the ecosystem we know today. Fossil burrows are helping scientists figure out how.

September 15, 2014

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9:38 PM | Geo 730: September 15, Day 623: Cheshire Cat
I've already posted a number of items about the Cheshire Cat Quarry in the Quartzville area; more on that in a moment. But when I was up there earlier this summer, I wanted to get a photo of the contact with something for scale. Unfortunately, the light wasn't good, and I didn't notice at the time, but the photo is poorly focused as well. However, the contact between the hackley-jointed basalt and the underlying buried soil (paleosol) is evident to Bobby's left- your right. That soil sits atop […]
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8:18 PM | The Weird Wind-Rippled Surface of Mars
In new observations beamed back from a NASA Mars orbiter, an example of transverse aeolian ridges has provided a clue as to how this strange wind-blown feature evolved. Continue reading →
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7:00 PM | Early Earth - Now A Lot Less Like Hell
The 500 million years after Earth formed were not the hot, lava-filled Hell commonly portrayed, it may have had oceans, continents and active crustal plates - a lot like we have today. This alternate view of Earth's first geologic eon, called the Hadean, gets support from the first detailed comparison of zircon crystals that formed more than 4 billion years ago with those formed contemporaneously in Iceland, which has been proposed as a possible geological analog for early Earth.read more
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3:30 PM | Life On Mars? Nakhla Martian Meteorite Has A Clue
A tiny fragment of Martian meteorite 1.3 billion years old contains a 'cell-like' structure, which investigators say once held water, according to findings published in Astrobiology. While investigating the Martian meteorite, known as Nakhla, Dr. Elias Chatzitheodoridis of the National Technical University of Athens found an unusual feature embedded deep within the rock. In a bid to understand what it might be, he teamed up with long-time friend and collaborator Professor Ian Lyon at the […]

September 14, 2014

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8:39 PM | Antarctica Rocks!?
Intro: One day hopefully, I will get there… but for now, I am starting this post with the truth. No, I have not been to Antarctica (yet!), but by a random chance of events I find myself the owner of a collection of rocks from Antarctica. How? Well, long story short, on the plane ride […]
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7:51 PM | Geo 730: September 14, Day 622: Liesegang 4
The final shot of Liesegang rings from this spot is a closer view of yesterday's outcrop. The black spots on older surfaces are manganese oxides. In dispersed forms, these can provide a purple coloration to rocks, but I'm betting most of the reds and oranges composing the rings are the result of iron oxides and hydroxides.Photo unaltered. June 14, 2014. FlashEarth Location.
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2:20 PM | Search for Missing Jet Reveals Ocean Secrets
Investigators have found no trace of the missing Malaysia Airlines Flight 370, but they have made groundbreaking scientific discoveries.

September 13, 2014

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6:39 PM | Geo 730: September 13, Day 621: Liesegang 3
The last two photos have been of a single, loose block, fallen from this outcrop. Here, we see the Liesegang rings in situ.Photo unaltered. June 14, 2014. FlashEarth Location.

September 12, 2014

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9:14 PM | Geo 730: September 12, Day 620: Liesegang 2
In early October of 1989, I was hired to do some geochemical reconnaissance mapping and sampling in this area. (See this post for some more information.) It involved following 200 foot contours (constant elevation), collecting samples from the soil B-horizon every 200 feet laterally, flagging sample sites, and mapping those locations as we went. One of the contours my field partner Mark and I were assigned happened to be at approximately the same elevation as this access road, which has been […]
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7:51 PM | Friday Headlines: 9-12-14
Friday Headlines, September 12, 2014 THE LATEST IN THE GEOSCIENCES   Today’s round-up: Parts of I-15 in Nevada destroyed by flooding! The oldest mammal? Exfoliation (in the geologic sense) caught on camera!   I-15 partially open from St. George to … Continue reading →
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5:10 PM | DIY Earthquake Alarm Made from Take-out Box
Simple $110 homebrew system taps into existing alert network to warn of impending seismic events. Continue reading →
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1:00 PM | Younger Dryas: Microscopic Diamonds Suggest Cosmic Impact Caused It
American cars didn't cause all climate change, no matter what you may have read. Around 13,000 years ago, a sudden, catastrophic event caused drastic climate change and much of the Earth was plunged into a period of cold climatic conditions and drought. This drastic climate change, now called the Younger Dryas, coincided with the extinction of Pleistocene megafauna, such as the saber-tooth cats and the mastodon, and resulted in major declines in prehistoric human populations, perhaps including […]

September 11, 2014

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8:45 PM | Real life pop rocks
Imagine you are just walking around the solid rock under your feet starts to crackle and then POP as pieces fly apart. This doesn’t normally happen. A big chunk of the Sierra Nevada caught fracturing on video | Ars Technica. One interesting way that rocks weather and crumble apart is called “exfoliation.” Like the skin-scrubbing… Source: Doubtful News
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7:46 PM | Geo 730: September 11, Day 619: Liesegang 1
Liesegang rings are, as we euphemistically say in the geo biz, "not well understood." In other words, we have some clues, but no one has managed to put the details together for a clear picture of how these are formed. No matter, they're fun and pretty; their mystery only adds to their appeal.This spot is maybe another 50 yards farther down the logging road past the bare area of the last two photos of the vein in the cut. Past that bare area, there's a copse of Douglas firs; as those start to […]
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