An earthquake has jolted Afghanistan, with tremors felt in neighbouring Pakistan.
Afghans on social media were the first to report the quake on Wednesday, late in the morning.
An Al Jazeera reporter in the Pakistani capital, Islamabad, said buildings in the city shook.
© USGS
A tsunami warning has been issued for Alaska, and a watch alert added in Hawaii after an 8.1 magnitude earthquake struck off the Alaskan coast.
According to the US National Tsunami Warning Center, the earthquake occured 175 miles (281.6 km) southeast of Kodiak City in Alaska at a depth of 12 miles (19.3 km), sparking the alert.
According to the Anchorage Office of Emergency Management, “A tsunami warning is now in effect which includes the coastal areas of British Columbia and Alaska from the Wash./BC border to Attu Alaska.”
“Tsunamis are a series of waves dangerous many hours after initial arrival time,” it said. “The first wave may not be the largest.”
A tsunami watch alert has also been issued for the state of Hawaii. “Based on all available data a tsunami may have been generated by this earthquake that could be destructive on coastal areas even far from the epicenter,” the Pacific Tsunami Warning Center said. “An investigation is underway to determine if there is a tsunami threat to Hawaii.”
Should a tsunami impact Hawaii, the first wave is estimated to arrive at 4:26 am HST (14:26 pm GMT). In Alaska, the estimated tsunami start time for Kodiak is 1:45 am AKST (10:45 am GMT).
Residents in several cities across Michigan reported seeing a bright and colorful flash travel through the sky before hearing a loud boom. The US Department of Homeland Security confirmed that it was a meteor fireball.
Numerous videos recorded by security cameras and dashcams in the Metro-Detroit area and surrounding cities Tuesday night show a flash of bright light zooming across the sky, instantly turning night into day for an instant.
Radioactivity in minerals are caused by the inclusion of naturally-occurring radioactive elements in the mineral’s composition. The degree of radioactivity is dependent on the concentration and isotope present in the mineral. For the most part, minerals that contain potassium (K), uranium (U), and thorium (Th) are radioactive.
Radioactivity is an attribute of minerals that contain radioactive elements. Radioactive elements are elements that contain disintegrating nuclei, emitting alpha rays, beta rays, and gamma rays. Uranium and thorium are the best known radioactive elements. Minerals that contain these elements in their chemical structure will be radioactive.
Radioactive minerals are unstable, meaning the elements in their structure continually break down. This destroys the mineral’s crystal lattice, causing it lose its crystal shape. When this happens, its crystal edges become rounded, and the mineral eventually becomes amorphous.
Radioactive minerals can be identified with special instruments that detect radiation. The device used to measure this is the Geiger counter. Electric charges develop in a Geiger counter when it is placed near radioactive material; this can measure the presence and intensity of radiation. Geiger counters are normally used by scientists and specialists, but collectors may also obtain inexpensive Geiger counters.
| Element |
Isotope |
Natural |
|
Primary |
| Tellurium |
130Te |
33.97% |
|
|
| Vanadium |
50V |
0.25% |
|
EC |
| Zirconium |
96Zr |
2.80% |
|
|
| Samarium |
149Sm |
13.80% |
|
alpha |
| Samarium |
148Sm |
11.30% |
|
alpha |
| Osmium |
186Os |
1.58% |
|
alpha |
| Neodymium |
145Nd |
8.30% |
|
alpha |
| Platinum |
192Pt |
0.79% |
|
alpha |
| Indium |
115In |
95.70% |
|
beta – |
| Gadolinium |
152Gd |
0.20% |
|
alpha |
| Tellurium |
123Te |
0.89% |
|
EC |
| Platinum |
190Pt |
0.01% |
|
alpha |
Samarium |
147Sm |
15.00% |
|
alpha |
Rubidium |
87Rb |
27.83% |
|
beta – |
Rhenium |
187Re |
62.60% |
|
beta – |
Lutetium |
176Lu |
2.59% |
|
beta – |
Thorium |
232Th |
100.00% |
|
alpha |
Uranium |
238U |
99.28% |
|
alpha |
Potassium |
40K |
0.01% |
|
beta – |
Uranium |
235U |
0.72% |
|
alpha |
Bubbles and cavities in frozen basaltic lava are frequently filled with a variety of beautiful minerals precipitated from circulating water rich mineralised fluids passing through the rock. As these fluids encounter changed temperature/pressure or chemical conditions they are no longer able to hold all their contents of dissolved elements and they have to leave them behind. Frequent fillers include zeolite minerals, calcite and various forms of microcrystalline silica such as agate, though the amorphous silica we see here was formed of tiny colloidal spheres that diffract the wavelengths of light to produce what gem people call play of colour. Mined at the Tablon mine in Honduras this dark matrix erupted in the early Tertiary (after the dino killing asteroid 65 million years ago) before being filled with the beautiful pinpoints of silican optics at some later stage in its geological journey through spacetime.
Somewhere in Eastern Tennessee the ground seems to quiver ever so gently, only to swiftly pass and leave those who felt it to question if it even happened. Seismologists record it, noting once again – far from the boundary of any tectonic plate – the soft rumble of an earthquake where none should be.
Often quiet, occasionally devastating, these shakes are nearly always perplexing. Now geologists think they have some idea of what’s causing them, and the answer lies deep beneath our feet.
As we learn in school, earthquakes are typically caused by the release of tension built up between the steady grind of Earth’s tectonic plates.
But every year there are hundreds of tremors far from plate boundaries, known as ‘intraplate’ earthquakes. They don’t have an easy explanation, but geologists have recently identified a common characteristic of a number of such earthquake locations.
The Canadian county of Charlevoix, US county of New Madrid, and the whole eastern third of Tennessee frequently experience earthquakes above a magnitude of 2.5, in spite of their distance from plate boundaries.
They also share a similar geology far underground.
“We present a new hypothesis that major seismic zones are restricted to places where the large-scale basement structures have been damaged by concentrated crustal deformation,” a pair of researchers from the University of Kentucky and the University of Memphis write in a new study.
This concentrated crustal deformation – or CCD – can include any activity that at some point in Earth’s history reduced the strength of the ancient rocky layers that make up the deepest parts of a continental crust.
The researchers claim the basement structures beneath a number of the sites where frequent intraplate quakes occur are associated with ancient plate reorganisations.
These scars would have been left hundreds of millions of years ago, only to have been reactivated over time.
The Charlevoix Seismic Zone (CSZ) provides a perfect example. The area stretches 85 kilometres (53 miles) along the Saint Lawrence River in southeastern Quebec, and has experienced five earthquakes greater than magnitude 6 since 1663.
Every year there are hundreds of microearthquakes, most too tiny to feel.
Not only is the CSZ is located on a set of faults deep in its basement, it is the site of a significant meteor impact that struck close to 360 million years ago.
The region’s earthquakes are mostly concentrated right where this collision occurred, with some rumbling up into the northeast for a short way along the faults.
On their own, the impact features and the faults wouldn’t be expected to produce earthquakes, making it a geologically curious anomaly.
Researchers have produced numerous models in an attempt to make sense of the area’s seismicity – whichever one they eventually settle on, it seems clear the deformation caused by the impact played a key role.
The New Madrid Seismic Zone has a different story. This one’s deformations were the product of repeated massaging of the crust following the breakup of the supercontinent Rodinia over half a billion years ago.
As for Eastern Tennessee, tension surrounding an abrupt kink within one of its deep faults resulted in something called a releasing bend – an extending of the crust along the fault that resulted in another kind of deformation.
“Although the mechanisms producing the CCD vary, the regionally restricted CCD serves to focus seismicity in these three zones,” the researchers write.
While necessary, these deformations might not be the only piece of the puzzle. Other stresses would be needed to turn a CCD into a seismic zone.
As usual, more studies are called for to flesh out the idea and determine the exact nature of each crustal deformation.
Given the challenges in predicting most earthquakes, though, knowing more about these peculiar hotspots is vital if we’re to arm ourselves against future activity.
Young paleontologist launches fundraising to restore the findings of two million years ago
POSSAGNO. A “small” rhinoceros, a long-tusked elephant and the distant relative of a deer graze the grass on the hills of Possagno. Two million years ago the area was a small “tropical” oasis, full of woods and ponds. The dinosaurs were already extinct, the man did not exist yet, the area was the ideal habitat for large herbivorous mammals.
Then came the glaciations, which brought prehistoric herds to extinction, but the traces of their passage were not lost. Almost thirty years ago, a trifle in the timeline, in the village of Steggio in Possagno, the earth began to give us back the past. A group of scholars began excavations and discovered the most important fossil deposit in Northern Italy dating back to the middle of the Villafranchiano medio. The clay in the subsoil had preserved skeletons and precious fragments of the primordial fauna. A stephanorhinus etruscus (rhinoceros), an archidiskodon meridionalis (elephant), a pseudodama nesti, very similar to a deer as well as the eucladocero. There are also a bison, a dormouse, a rodent and many other small mammals. All the discovered material is finished at the Possagno museum but, as often happens in Italy, resources were lacking to enhance the cultural heritage. There was a risk that everything would end up in the dust. Fortunately, it did not happen that way. The project resumes today vigor thanks to the commitment of a young paleontologist, Elena Ghezzo, 33, originally from the Lido of Venice, who decided to rekindle the light on the fossils of Steggio, starting an online fundraising campaign to activate a program of research and comparison. “Despite the considerable importance, the Steggio site is virtually unknown internationally, and it is a pity. I would like to try to renew the interest on the local level and also across the border, “says the paleontologist. At his side in this ambitious challenge his colleagues Mauro Bon and Marzia Breda, as well as the laboratory technician Paolo Reggiani. “We obtained the permits from the Municipality and the Superintendency and now the material is at the Museum of Natural History of Venice. Not having funds, we thought that the quickest way was to try the GoFundMe site where everyone can donate something if interested »adds Ghezzo. The goal is to reach 7 thousand euros as soon as possible, since the permits for the study will probably expire in the spring of 2018. “If we reach the fixed budget we will be able to digitize the material and compare it with some fossil collections in Spain and Germany. ahead of the studies on the fauna “the expert points out. It will be like seeing the biodiversity of our planet aboard the time machine. «The comparison with the species found in other countries will allow us to understand how they evolved, their characteristics and knowledge of which animals were present even if they have not been preserved, “says Ghezzo. His long curriculum reveals many experiences as a “hunter” of fossils: from the finds of Bolca to the restoration of a horse to the archaeological museum of Oderzo, while in Turin he worked on an African loxodonta and a megatherium, respectively relatives of an elephant and of a sloth. Being able to read the fossils of Steggio, however, has a special charm. “Since I was a child, I loved the natural sciences,” he explains. “Being able to give the right visibility to the Treviso site means reconstructing a moment of life that no longer exists”. Another important piece would be added to the genealogical tree of the Earth. His long curriculum reveals many experiences as a “hunter” of fossils: from the finds of Bolca to the restoration of a horse to the archaeological museum of Oderzo, while in Turin he worked on an African loxodonta and a megatherium, respectively relatives of an elephant and of a sloth. Being able to read the fossils of Steggio, however, has a special charm. “Since I was a child, I loved the natural sciences,” he explains. “Being able to give the right visibility to the Treviso site means reconstructing a moment of life that no longer exists”. It would add another important piece to the genealogical tree of the Earth. His long curriculum reveals many experiences as a “hunter” of fossils: from the finds of Bolca to the restoration of a horse to the archaeological museum of Oderzo, while in Turin he worked on an African loxodonta and a megatherium, respectively relatives of an elephant and of a sloth. Being able to read the fossils of Steggio, however, has a special charm. “Since I was a child, I loved the natural sciences,” he explains. “Being able to give the right visibility to the Treviso site means reconstructing a moment of life that no longer exists”. It would add another important piece to the genealogical tree of the Earth. respectively relatives of an elephant and a sloth. Being able to read the fossils of Steggio, however, has a special charm. “Since I was a child, I loved the natural sciences,” he explains. “Being able to give the right visibility to the Treviso site means reconstructing a moment of life that no longer exists”. It would add another important piece to the genealogical tree of the Earth. respectively relatives of an elephant and a sloth. Being able to read the fossils of Steggio, however, has a special charm. “Since I was a child, I loved the natural sciences,” he explains. “Being able to give the right visibility to the Treviso site means reconstructing a moment of life that no longer exists”. Another important piece would be added to the genealogical tree of the Earth.
© RESERVED REPRODUCTION
These beautiful rocks form during the transformation of sediments into rock, as detailed in our past post on concretions (see http://tinyurl.com/pwfs2tf). The septaria are the calcite filled cracks at the centre of the rock, indicating where the centres of the concretions have shrunk, possibly during dehydration during its long transformative journey. The actual process of formation remains unclear, and also include expansion of gases from decaying organic matter and fracturing by compaction from the weight of overlying sediment or tectonic pressure.
The most famous septarian nodules are the Moearaki Boulders, found weathering out of a Paleocene mudstone in South Island New Zealand (see http://tinyurl.com/lf35859). This specimen came from Utah, measures 14.5 x 12.8 x 7.5 cm and includes some beautiful blades of baryte within the concretion as well as the surrounding calcite
Loz
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Image credit: Rob Lavinsky/iRocks.com
At least 64 modern species of mammals are known to have developed the ability to glide. Usually it involves evolution of long limbs, complex musculature to support the body during gliding, and an elongate tail for balance.
There are also many potential gliding mammals known from the fossil record – up to 80 proposed, although some are still debated. Only 3, however, date back to the Jurassic era, when mammals were first diversifying and the dinosaurs ruled the Earth. This critter, found in a fossil pit in Nanshimen village, Hebei Province, China, is the 3rd. It is 159-164 million years old and well preserved, including remnants of the gliding musculature and the tail.
This sample is so old that much of the paper published displaying this sample involves actually identifying it as a mammal. The authors, including scientists from China Hainan Tropical Ocean University, closely examined the bones of the jaw and of the ear – key changes associated with the earliest mammals – to verify that this creature is a mammal and to give it a proper name. The full name is Arboroharamiya allinhopsoni, with the species name given in recognition of two scientists who have worked on early mammal evolution.
The uppermost layer in the package of sedimentary rocks representing the Grand Canyon is the Permian aged Kaibab Limestone, just over 250 million years old. That was not the last sedimentary unit deposited in what is today Arizona and Utah. That area continued to see sedimentary rock deposition until the Cretaceous – nearly 200 million years more sedimentary layers on top of the Grand Canyon layers.
Those layers aren’t exposed at the Canyon site any more; they’ve eroded away. To the north of the Grand Canyon, the sedimentary package gently folds and is faulted down, exposing layers that are stratigraphically above those at the Canyon. Some of these younger layers are eroded into their own spectacular features – the Navajo Sandstone, for example, makes up much of the exposure in Zion National Park. The Navajo Sandstone is just one of more than a dozen sedimentary units that formed in this area.
Just like in the Grand Canyon, these units vary in their properties. Some are well lithified and make steep cliffs like the Navajo Sandstone does, others are weaker and erode back easily. Just as in the Grand Canyon, this setup creates a “Stairstep” pattern, where the landscape steps upwareds at the edge of a resistant layer and then erodes away at a weaker layer.
Southern Utah, to the north of the Grand Canyon, therefore, is a gigantic geologic stairstep pattern. This area is nicknamed the “Grand Staircase”. You get that impression in this picture from the central part of the area – stairstepping geologic units.
In the 1990s, President Bill Clinton used the power of an early 20th century bill called the Antiquities Act to declare much of the Grand Staircase part of “Grand Staircase-Escalante National Monument”. The original power to declare National Monuments was established in part to allow rapid protection of historical relics without the approval of Congress, which is required to create a full national park, but Presidents have historically used this power to set aside large areas for protection. It is often controversial as setting aside territory for protection means that you can’t make money on the area by tearing it apart, but this power has been used in the past to protect areas including what is today Grand Canyon National Park just to the south – Congress often eventually turns National Monuments into National Park sites once enough visitors begin coming to the area.
On Monday, something that has never happened is apparently going to happen. No President has ever shrunk a National Monument – in fact none has ever tried to do so. President Donald Trump is coming to Utah on Monday to declare that he will shrink Grand Staircase-Escalante National Monument and one other, Bears Ears National Monument, created by President Obama just over a year ago.
We don’t yet have maps of the areas that will be removed from the national monuments, and some areas have been declared Wilderness areas and have additional protections against development, but there’s a good chance that this photo will not look the same in a few years. The central part of Grand Staircase covers a coal-bearing unit and if the geotag on this photo is correct, this photo sits right above that coal-bearing unit. There are other natural gas deposits in the park as well, and local officials who have submitted maps of new park boundaries typically make sure these areas are outside the National Monument so that they can be mined and drilled.
Earlier this year, the US Interior Secretary allowed public comments about what to do with these monuments and the comments were overwhelmingly in favor of keeping them as they were – a required step before making such a change. There are local officials who want to open these areas to drilling and grazing, and the changes will be basically choosing their voices over the voices of the people who submitted comments.
It is uncertain what will happen when they try to do this. The text of the Antiquities Act gives the President the ability to declare a monument but there is no law stating how a monument can be undeclared, so there will likely be a long legal case. But…if they do what they want to do, the area in this photo will one day host a coal mine.
Image credit:
Geology Insider 
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