Posted on 05/08/2017 1:25:53 PM PDT by JimSEA
More than 90% of Earth's continental crust is made up of silica-rich minerals, such as feldspar and quartz. But where did this silica-enriched material come from? And could it provide a clue in the search for life on other planets?
Conventional theory holds that all of the early Earth's crustal ingredients were formed by volcanic activity. Now, however, McGill University earth scientists Don Baker and Kassandra Sofonio have published a theory with a novel twist: some of the chemical components of this material settled onto Earth's early surface from the steamy atmosphere that prevailed at the time.
First, a bit of ancient geochemical history: Scientists believe that a Mars-sized planetoid plowed into the proto-Earth around 4.5 billion years ago, melting the Earth and turning it into an ocean of magma. In the wake of that impact -- which also created enough debris to form the moon -- the Earth's surface gradually cooled until it was more or less solid. Baker's new theory, like the conventional one, is based on that premise.
The atmosphere following that collision, however, consisted of high-temperature steam that dissolved rocks on the Earth's immediate surface -- "much like how sugar is dissolved in coffee," Baker explains. This is where the new wrinkle comes in. "These dissolved minerals rose to the upper atmosphere and cooled off, and then these silicate materials that were dissolved at the surface would start to separate out and fall back to Earth in what we call a silicate rain."
To test this theory, Baker and co-author Kassandra Sofonio, a McGill undergraduate research assistant, spent months developing a series of laboratory experiments designed to mimic the steamy conditions on early Earth. A mixture of bulk silicate earth materials and water was melted in air at 1,550 degrees Celsius, then ground to a powder. Small amounts of the powder, along with water, were then enclosed in gold palladium capsules, placed in a pressure vessel and heated to about 727 degrees Celsius and 100 times Earth's surface pressure to simulate conditions in the Earth's atmosphere about 1 million years after the moon-forming impact. After each experiment, samples were rapidly quenched and the material that had been dissolved in the high temperature steam analyzed.
The experiments were guided by other scientists' previous experiments on rock-water interactions at high pressures, and by the McGill team's own preliminary calculations, Baker notes. Even so, "we were surprised by the similarity of the dissolved silicate material produced by the experiments" to that found in the Earth's crust.
Their resulting paper, published in the journal Earth and Planetary Science Letters, posits a new theory of "aerial metasomatism" -- a term coined by Sofonio to describe the process by which silica minerals condensed and fell back to earth over about a million years, producing some of the earliest rock specimens known today.
"Our experiment shows the chemistry of this process," and could provide scientists with important clues as to which exoplanets might have the capacity to harbor life Baker says.
"This time in early Earth's history is still really exciting," he adds. "A lot of people think that life started very soon after these events that we're talking about. This is setting up the stages for the Earth being ready to support life."
I dunno... I think G-d created the whole thing all at once...
For 4,500,000,000 years our planet has been rolling around in the cold of space managing to maintain a molten core.
My thermos can’t keep my soup warm until lunch.
I can read, but I’m afraid this is way beyond my education & comprehension. The layers of rock along the Smoky Mountains are stunning and I have wondered how they were formed.
Thank you for posting.
>>>I dunno... I think G-d created the whole thing all at once...<<<
And I think when I read articles like this, the scientific community worships the creation.
.
He used Krusteaz too!
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God gave man the gift of intellect, curiosity and wonder, so that we (some of us) could understand His Creation.
I too, believe that scientists understand the existence of God, the creator of the Universe. There is no other explanation.
You need a new thermos.
Baked at 350 for twenty minutes? :D
How was it created? Exnihilo......
Whatever, I stopped reading with interest after the first “it is believed”.
Flame on scientism followers.
My thermos can’t keep my soup warm until lunch.
Your soup is not heating itself with the decay of radioactive elements. (At least I assume it isn't.)
I’m pretty sure you won’t find a better description than this:
And God said, “Let the waters under the heavens be gathered together into one place, and let the dry land appear.” And it was so. God called the dry land Earth, and the waters that were gathered together he called Seas. And God saw that it was good.
Pressure and Thermodynamics are what keeps the center of the earth molten hot.
Look at what the scientists had to go through to recreate what they think happened to make the Earth’s crust. Everything had to be just right. The calculations and the environment had to be just so. The only thing that explains it is GOD.
So I need radioactive soup.
I wonder if I can get that in tomato?
Baked in the sun’s ray’s till the crust was just right then left to cool for billions of years.
A hypothesis which fits several observations is being put forward. Now some other scientists will see if they can poke holes it through their examination of these observations and by seeing if other observations fit. We can look eventually at planets in other solar systems and see if we see anything like this going on. It has nothing to do with religion.
Silicate rain. Molten glass, basically. All the rain we get in Oregon doesn’t seem so bad by comparison.
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