geophysics

phantom-white asked:

I see all these cool pictures you post and was wondering if there's a specific field you can go to college for to be able to go out and find this stuff. Obviously there's a lot that goes in to finding minerals or neat rocks, but any answers would be appreciated. :)

Hell yeah, that’s what our blog is all about: mineralogy!! Mineralogy is really a subset of the field of geology, as mineralogy is technically only the study of the chemical and physical properties of minerals. Other fields within geology would include petrology (the study of how and where minerals form), biogeochemistry (just what it sounds like: a mix of biology, geology and chemistry, I’m not super familiar w it), paleontology (the study of fossils), the list goes on and on. If you were to look through your college classes, it would probably fall under earth sciences, geophysical sciences, probably something like that depending on the school. 

If you have further questions feel free to send them in and I’ll direct them to Lara, as she graduated in geophysical sciences with me and her family is in the industry. 

Good luck!!! :) I hope that was helpful for you!

-Z

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A lot of people have been mislead by a post that talks about the “lumpy” Earth, and unfortunately it seems that people genuinely believe the Earth is this shape. As one person pointed out, we have images of the Earth from space, and while it would be disingenuous to refer to it as a perfect sphere, it very much is spherical. A rudimentary reverse Google image search tells me that the image in the misleading post is a simulation of the Earth without water… which is just plain wrong.

In fact, the shape you’re seeing is a geoid, which is a simulation of what Earth would look like if you neglected the influence of anything other than rotation and gravity. A geoid is a dynamic equipotential surface, which means that every point on the surface has the same gravitational potential.

Since it was recently NASA’s Astronomy Picture of the Day, this seems like a good opportunity to talk about a geoid that is something more than a context-less gif: the Potsdam Gravity Potato, pictured above. It’s the result of efforts by a group at Helmholtz Centre Potsdam to create a highly detailed map of the Earth’s gravitational field. Like in a heat map, red elevated levels indicate stronger gravitational effects, and depressed blue levels indicate that they’re lower. The potato-like shape occurs due to the Earth’s uneven gravitational field. This is why high places such as the Himalayas coincide with local maxima on the geoid—but of course not all maxima and minima are the result of noticeable physical features; the Earth has inhomogeneous variations in its density, which account for much of the gravitational difference.

For further reading, check out this article.

Heart-Shaped Glomerocryst Photomicrograph

While studying samples of lavas from the Aeolian Islands off the west coast of Italy, I came across an interesting aggregate of crystals (glomerocryst).

A photomicrograph thin section of the aggregate is featured above. Aeolian lava is studied to understand how magma forms at depth and the level of risk of its eruption. This particular glomerocryst is made of two minerals; plagioclase and pyroxene, whose chemical compositions, textures and melt inclusions help decipher just what happens in a magma chamber.

But, if you look closely at its shape, you might learn something more – that even something as hard as a rock has a heart.Bernardo Cesare

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Antarctic Lake Vostok buried under two miles of ice found to teem with life

A giant lake buried more than two miles beneath the Antarctic ice has been found to contain a “surprising” variety of life.

Analysis of ice cores obtained from the basin of Lake Vostok, the subglacial lake that Russian scientists drilled down to in 2012, have revealed DNA from an estimated 3,507 organisms.

While the majority were found to be bacteria, many of which were new to science, there were also other single celled organisms and multicellular organisms found, including from fungi.

The diversity of life from the lake has surprised scientists as many had thought the lake would be sterile due to the extreme conditions.

Lake Vostok was first covered by ice more than 15 million years ago and is now buried 12,000 feet beneath the surface, creating huge pressures. Few nutrients were expected to be found.

However, samples of ice that had formed as water from the lake froze onto the bottom of the glacial ice sheet above have revealed it is teeming with life.

This will raise hopes that life may be found in other extreme environments on other planets. One of Jupiter’s moons, Europa, for example, is covered with an icy shell that may hide a liqud ocean below where life could exist.

Dr Scott Rogers, a biologist at Bowling Green State University, in Ohio, and led the DNA analysis of biological material found in the ice cores, said:

“We found much more complexity than anyone thought. It really shows the tenacity of life, and how organisms can survive in places where a couple dozen years ago we thought nothing could survive. The bounds on what is habitable and what is not are changing.”

Lake Vostok is around 160 miles long and 30 miles wide, covering an area of more than 6,000 square miles beneath the Antarctic ice sheet.

Among the bacteria found in the samples brought to the surface were those commonly found in the digestive systems of fish, crustaceans and annelid worms, raising the prospect there could be more complex life still living in the lake.

Isolated from the rest of the world for 15 million years, some of the DNA sequences were found to be unique to science and may belong to new species that have evolved in the depths.

Writing in the journal PLOS One, Dr Rogers and his colleagues said:

“The sequences suggest that a complex environment might exist in Lake Vostok. Sequences indicating organisms from aquatic, marine, sediment and icy environments were present in the accretion ice. In addition, another major proportion of the sequences were from organisms that are symbionts of animals and/or plants. Over 35 million years ago, Lake Vostok was open to the atmosphere and was surrounded by a forested ecosystem. At that time, the lake, which might have been a marine bay, probably contained a complex network of organisms. As recently as 15 million years ago, portions of the lake were ice free at least part of the time. During these times, organisms were likely being deposited in the lake. While the current conditions are different than earlier in its history, the lake seems to have maintained a surprisingly diverse community of organisms. These organisms may have slowly adapted to the changing conditions in Lake Vostok during the past 15–35 million years as the lake converted from a terrestrial system to a subglacial system.”

via telegraph.uk

I reserved posting this immediately because I wanted to give this more attention, visuals and include a link to my other shared posts on Lake Vostok.

Oh and everything you need to know about why this is so incredibly and astoundingly important can be found in the documentary “The Lost World of Lake Vostok”.

Details (via TDF): In 1957 the Russians established a remote base in Antarctica – the Vostok station. It soon became a byword for hardship – dependent on an epic annual 1000km tractor journey from the coast for its supplies. The coldest temperature ever found on Earth (-89°C) was recorded here on the 21st July 1983. It’s an unlikely setting for a lake of liquid water. But in the 1970’s a British team used airborne radar to see beneath the ice, mapping the mountainous land buried by the Antarctic ice sheet. Flying near the Vostok base their radar trace suddenly went flat. They guessed that the flat trace could only be from water. It was the first evidence that the ice could be hiding a great secret.

But 20 years passed before their suspicions were confirmed, when satellites finally revealed that there was an enormous lake under the Vostok base. It is one of the largest lakes in the world – at 10,000 square km it’s about the extent of Lake Ontario, but about twice as deep (500m in places). The theory was that it could only exist because the ice acts like a giant insulating blanket, trapping enough of the earth’s heat to melt the very bottom of the ice sheet.

The Center of the Earth Is as Hot as the Sun

Crushed by the weight of the thousands of kilometers of liquid iron and sulfur, superheated metal and minerals and cool crustal rock above, the Earth’s core is under immense pressure. Heated from within by friction and by the decay of radioactive material and still shedding heat from the initial formation of the planet 4.5 billion years ago, the planet’s core is blisteringly hot. In new research, scientists studying what the conditions at the core should be like found that the center of the Earth is way hotter than we thought—around 1,800 degrees hotter, putting the temperature at a staggering 10,800 degrees Fahrenheit.

This superheated core, says the BBC, is about as hot as the surface of the Sun.

Scientists know the Earth’s core, a multi-layered structure with a solid iron core spinning in a sea of liquid iron and sulfur, is hot. But, cut off from direct study by all the stuff in between the core and the surface, getting an accurate idea of the core’s properties is a daunting feat.

Led by Simone Anzellini, the French research team did their best bet to reproduce the core’s properties in the lab: they took a bunch of iron and crushed it between two pieces of diamond. Then they shot it with a laser. The apparatus produces massive pressures and superheated temperatures. This let them study how the iron behaved under such intense conditions and gave them a window into the conditions found at the planet’s center.

Knowing how hot the Earth’s core is can add to our understanding all sorts of wonders, from the existence of the planetary magnetic field, to the propagation of seismic waves after an earthquake, to the birth of the Earth itself.

Full Article

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Layers of the Grand Canyon: The Trail of Time

This morning I visited the Grand Canyon and along the trail that runs along the south rim there is a segment called “The Trail of Time.”, which showcases several different types of rock taken from the various layers of the Grand Canyon. 

The first rock you encounter at the trailhead, also the oldest rock of the collection, called Elves Chasm gneiss (pronounced “nice”) is about 1,840 million years old, or 1.84 billion years old. As you move along the trail you see about 15 other rocks all in descending order of age until you finally come to the last one called Phantom granite, which is a mere 1.66 billion years old.

All photos were taken by me.

source

Venus’ crust heals too fast for plate tectonics

The emergence of plate tectonics is arguably Earth’s defining moment, the authors of a new Nature paper write. Out of all the planets we’ve looked at carefully, Earth is the only one that has a hard outer crust with distinct pieces that shift and move. Our home is unique in its continents and quakes.

Some scientists think that plate tectonics are essential for life—so much so that if they could figure out a way to spot tectonic action on exoplanets, they think it would be a good indication that there might be life there, too. Tectonic activity recirculates minerals and recycles carbon. As one plate slides under another (a process called subduction), it pushes carbon down into the mantle with it.

Without plate tectonics, carbon would build up in the atmosphere. Venus, which does not have tectonics, shows the results: an atmosphere that is 96 percent carbon dioxide. It’s toxic. Yet Venus is about the same size and composition as our planet, so why doesn’t it have plate tectonics?

Keep reading

Earth’s Rotating Inner Core Shifts Its Speed

Earth’s solid-metal inner core is a key component of the planet, helping to give rise to the magnetic field that protects us from harmful space radiation, but its remoteness from the planet’s surface means that there is much we don’t know about what goes on down there. But some secrets of the inner core are being revealed by acoustic waves passing through the planet’s heart and iron squeezed to enormous pressures in the lab.

Two new studies, both detailed online May 12 in the journal Nature Geoscience, reveal that Earth’s inner core may actually be softer than previously thought, and that the speed at which it spins can fluctuate over time.

Under the liquid-metal outer layer of the Earth’s core is a solid ball of superhot iron and nickel alloy about 760 miles (1,220 kilometers) in diameter. Scientists recently discovered the inner core is, at 10,800 degrees Fahrenheit (6,000 degrees Celsius), as hot as the surface of the sun.

Churning in the liquid outer core results in the dynamo that generates Earth’s magnetic field. Geoscientists think interactions between the inner and outer cores may help explain the nature of the planet’s dynamo, the details of which remain largely unknown.

“The Earth’s inner core is the most remote part of our planet, and so there is a lot we don’t know about it because we can’t go down and collect samples,” said Arianna Gleason, a geoscientist at Stanford University in California. 

Full Article

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NEW VIDEO!!!

Human beings have only been able to drill down a third of the way into Earth’s crust. That’s only about 0.3% of the radius of the Earth. So how we know so much about its internal structure?

In this week’s It’s Okay To Be Smart, you’ll earn why the Earth is organized like an onion filled with sizzling magma and metal as hot as the sun, plus how it got to be that way. You’ll also discover how the leftovers from dying stars and a little bit of density put “life” in Earth’s destiny. 

Enjoy! If you like the videos we’re making, please consider subscribing and share with your friends!

PS - My t-shirt game is strong in this one, if I do say so myself.

I’ve always been a proud skeptic of the (alarmism on) Anthropogenic Global Warming, and now I’m very happy to fully endorse this recap (Know the Facts - A skeptic’s guide to climate change) from berkeleyearth.org and its main conclusions (my comments in brackets):

  • Stay skeptical (always)
  • Practice and promote energy efficiency (by principles)
  • Recognize that most future emissions will come from China and the developing world (and Science and technology depends on that, and they are the only thing who eventually could save us from a global crisis)
  • Demand sustainable and cost-effective solutions in the US and around the world (yep, pragmatism should be always above politic, and, of course, above science tainted by politics).

So please, do not let that some interested people (or gullible persons or guided by a specific agenda) to use Science (and propaganda) in order to impose damaging policies for everyone in general, and for developing countries in particular. Not in the name of Science, it does not work, Science always win, because…

….reality must take precedence over public relations, for nature cannot be fooled.

Richard Feynman

EDIT

I knew that some people would go to bray about this entry:

- “Um, no. Simply wrongheaded and idiotic. Nothing personal, but I pity you…

(I only see idiocy in your comment, in bulk, read the report please)

- “Hey if that makes you feel better about driving your SUV……

(I have no car, I use public transport)

(more surely coming next)

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wiredclover (and calitony who echoes him) seems not happy with the “pamphlet” because it broke with the (unfounded) alarmism, and probably because does not call “negationist” to skeptics. The fact is that everything in the paper is true (as established data), and everything trying to go farther is or propaganda, or delusions, or pseudoscience… typically a mixture of all three.

To view the state of the art (and debate) on the subject, I recommend to take a look at climatedialogue.org you will see that discussions are due to the uncertainties and ignorance of many mechanisms, and the one who sells certainty there where there is not, is the one who has to explain their arguments, not the people recognizing the uncertainties.

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battalio complains that the data (??) are self referring to their own research (not peer-reviewed), totally losing the scope of this paper: a basic compilation of what is known and omitting what is mere speculation.

About the claim “sea levels are going to rise catastrophically” there is no sign of it, and the “catastrophic” rise of sea level already occurred 15,000 years ago as befits an interglacial period:

The chances of a future catastrophic growth in sea level (or not) will depend on our ability to adapt, not of the CO2 emissions, as far as climate sensitivity is quite certainly much less that 3 C per century (IPCC itself has not been able to give a “more likely data”  in the AR5 report, and indeed they decreased 0.5° the lower limit).

Of course there are all kinds of speculation (unverifiable and infansables, ie pseudo-scientific), but analysis of the data leave little room for alarmism.

Also says:

I also hate it when people misappropriate the quotes of scientists with no context, thinking that it will prove their point.

Well, the context was Feynman complaining about politization of science (on the affair of  challenger disaster), I supposed that most of the readers would realize this. And this is the problem of Climate Change “Science”, it is all about politic, and economy, and geostrategy, i.e. is a Social Science with no prediction capacities.

I’m very disappointed in this blog.

I’m sorry on that, but I can do nothing about.

“benlylebedard said: Pseudo-science is beauty. Unfollowed.”

I’m sorry, but I will surely get over the loss.

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Dear battalio, first of all thanks for your tone. And you’re right, English is not my first language, and maybe that will influence when I try to find the right words to explain my feelings. In any case I’ll try again.

I don’t understand why you don’t like the term “proud skeptic”. Being skeptic on Climate Change is not an easy task (is neither easy nor as a blogger or as a geophysicist), you are exposed to all kind of insults, falacies, and pure lies. And that is why finding a site that clearly explains that we do not deny most of the facts, is already in itself a step forward, and for that reason I have highlighted them in Science is Beauty, and because I also affirmed that I am proud to be skeptic (no denier).

About sea level I’d like to say that I have linked this paper on purpose because does not displays predictions, shows only trends and acceleration in observations (facts), and everything else are speculations, more or less believable or grounded, but speculations.

You can’t say (well, you shouldn’t)

“In several centuries we will have a terrible problem.” [because the humans/because the CO2]

First because you don’t know the emissions 20, 50, 100, 200 years from now. Nobody knows, and nobody knows about the energy mix for these years. Nuclear fusion, new generation of fission, renovable energies… who knows…

Second because even knowing these (essential) parameters, we don’t know several mechanisms on feedbacks and sensitivities… After 150 years of climatology our understanding of the climate is better, but we still have essentially a very basic and low predictive reliability knowledge.

Not recognizing this things is to trick people, and trick people is Politics not Science. We have many (real) problems, even human generated problems (pollution, deforestation), and diseases, poverty, wars… to invent other problems based on speculation and admittedly incomplete numerical models.

In short, my opinion is that everything is very exaggerated, politically contaminated, and in the hands of lobbies (falsely) environmentalists and companies of renewable energy (not far of the Big Oil). The Science behind seems too weak to me, so it is absurd speaking of the future with such certainty, is a mirage. Makes me this a monster…? it may be so, but we’ll see who is closer to the truth.

Cheers!

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Marked-point says: “i don’t like your thinking, though i can’t say that i believe even 80% that global warming is real, i do think that people have caused a problem with burning fossil fuels.”

Yep, nothing is free, everything has cost, but in my opinion, in the overall calculation, the last two centuries have been the most productive for humans, and have laid the foundation for solving many problems, including those generated by ourselves. I try to be optimist, not a dreamer.

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battalioI assure you that I have thanked your friendly tone most sincerely (you do not know the stupid things I’ve been call here as soon as I’m out of political correctness). So I thank you again your politeness because not always is possible to interchange opinions in this way.

I think that the problem with the wording (skeptics and/or anti-alarmist) is included in my criticism to climate alarmism. There are very few skeptics (skeptics of alarmism I mean) who deny what alarmists say that we deny. And I have featured this initiative in Science is Beauty, precisely for this very reason. Because it explains to people that many of the things that climate science affirms, are accepted for most of the people involved on this business, regardless of the degree of skepticism.

Of course there are also crazy people, as those who deny the greenhouse effect or things like that, but that has nothing to do with the healthy scientific skepticism (I’m thinking in Richard Linzden, Roy Spencer, Judith Curry and thousands of other unknown scientists). And this is the skepticism I’m claiming, legitimately I think.

I’m physicist, I understand many of the problems who arise from trying to predict climate. I know we have mechanism with a big uncertainty (aerosols and clouds mainly, but could be more as cosmic rays and its influence in nucleation of clouds, its dependency on solar cycles…), and so I am wary with (many) predictions, at least of its emphatically certainty when stating something that it’s only remote possibilities.

Real science, and real scientist never speak with that certainty, because they know it is not real. And when someone say we are going to die tomorrow (or in 2050 for that matter), as I said before, it’s not science. There is a political message more or less hidden which can be legitimate or not, but that discussion is not science, it’s policy. And they are two topics that mix poorly (and this is too the meaning of Feynman in this talk)

Finally, that it is very late here, I have not read your link to Science, I will try it tomorrow, but remember that we’re not talking about sea rises itself, we speak of the responsibility of CO2 (our CO2) in them, and of its catastrophic nature.

Best Regards

Jose Angel

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What Is Fracking?

The fracking frenzy in North Dakota has boosted the U.S. fuel supply — but at what cost? Watch this video animation to see how the process of hydraulic fracturing, or fracking, is used to extract oil and natural gas from shale formations deep underground.

by National Geographic.


Climate Change Is Making the Whole Planet Tip

Climate change is changing the planet. Yes, it’s doing it in all those ways that you already know about: rising seas, rising temperatures, changing rainfall patterns, more extreme weather. But climate change is changing the planet in another dramatic way, too: It’s actually causing the entire crust of the Earth to shift. According to new research by Jianli Chen and colleagues, climate change–induced glacier melt and sea level rise have thrown the whole planet off-kilter.

The Earth is a ball that floats in space, and the Earth’s surface—the tectonic plates that make up the land—are like a shell that floats on the mantle below. Just like the hard chocolate coating can slip and slide on your soft serve ice cream, the crust of the Earth can slide over the mantle. This is different than continental drift. This is the whole surface of the planet moving as one. The rotation axis of the Earth stays steady, the land masses shift around it. The idea is known as “true polar wander,” and its occurrence is a part of the planet’s history.

The Earth is not a perfect sphere—it’s kind of fat at the middle—and changing how the mass on the surface is distributed changes how the tectonic plates sit in relation to the planet’s rotation axis. By melting Greenland and other glaciers, say the researchers, the Earth’s geographic North Pole has drifted to the east at around 2.4 inches each year since 2005. Nature:

From 1982 to 2005, the pole drifted southeast towards northern Labrador, Canada, at a rate of about 2 milliarcseconds — or roughly 6 centimetres — per year. But in 2005, the pole changed course and began galloping east towards Greenland at a rate of more than 7 milliarcseconds per year.

Seasonal shifts in how ice and water are spread around the world mean that the North Pole is always sort of wandering around. But drift triggered by climate change is new. It’s a sign that global warming isn’t just changing how we might live in the world, but the very face of the world itself.

Misconception About Tsunamis

Tsunamis in the middle of the ocean are usually just centimeters in height, not the 10m killer waves they are when they reach the shore.

This is due to the conservation of momentum - 

The velocity of a wave, V, is proportional to the depth of the water it is travelling over, so in deep seas waves are travelling very quickly, and naturally have large Wavelengths, L.

Because the wave has a large wavelength it will also have a large mass, even if its only a few centimeters tall, as Mass is proportional to L and H. and Momentum = Mass X Velocity.

So a large Mass X large Velocity = Large momentum.

But as the wave approaches the shore, depth decreases.

V = SqRt( Gravity X Depth )  so if the depth is 4 times shallower, velocity is halved.

So now we have Mass X (Velocity / 2) = Momentum, But momentum must be conserved! so Mass is doubled, but if the Wavelength is not changed how can the wave gain mass? 

So, as a Tsunami approaches the shore, ocean depth obviously decreases. Which in turn decreases Velocity, meaning mass must increase which means Height must increase!

Which is why those movies of boats being flung out of the ocean and capsized by massive waves in the middle of the ocean is incorrect. You probably wouldn’t even noticed it!