I don't think that was a bug, looks like more of a sign of AI on the browser's part.
Of course Earth's systems evolve.
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Evolving Rocks
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· Score: 2, Insightful
Minerals are just like any other chemical species on earth. They react with one another, and form into new and more diverse populations based on a variety of fundamental thermodynamic factors. Since the earth's processes have changed and evolved since planetary accretion, it only makes since that the assemblages of minerals we see on the earth would evolve in much the same way.
It appears that this paper focuses primarily on the biological effects on mineral speciation, but there have been a variety of geologic affects that have had equally profound impacts on the earths mineralogy (which in turns defines the variety of rocks we see). Factors such as the development of the earths core, mantle, and crust, plate tectonics, the development and evolution of our atmosphere and hydrosphere, and then of course the evolution of biota and related biogenic sedimentary rocks are all going to have an effect on the mineralogic evolution of the earth.
Wowzers. I am not sure where you get your information but it is coming WAY out of left field. First of all, when dating zircons (or any other mineral for that matter) we are primarily interested in the ratios of one isotope to another, not the finite amounts of U or Pb (which is very difficult ot measure accurately). The structure of the zircon can be important, because you have several different growth events, which would lend different ages, but we can use analytical techniques to see through a lot of this. This 4.28 Ga age was not found through U-Pb zircon geochronology, it is had there would not be a debate in the Geology community. It was actually a whole rock study that yielded this much older date, which is what makes it questionable, because a whole rock study could be dating the rock, or could be dating its protolith (the material from which it formed).
There is a process called fission track dating that actually counts the number of paths of alpha particles through the crystal structure (think helium nuclei being shot out into the crystal and leaving destruction in their wake), which represents the number of decays. But this is rarely done in zircon, it is more typical in minerals like apatite, sphene, and micas.
The dating process for zircon used most commonly on this type of rock is called TIMS (thermal ionization mass spectrometry), and this involves crushing a portion of the rock, separating zircon crystals, dissolving them in acid, separating out the U and Pb through a column chemistry process, and then using a TIMS to ionize the U and Pb, and measure the ratio between the different isotopes. Which actually yields 4 different dates for the zicron grain, which can be used to cross check one another.
Re:Discovery of world's oldest rocks challenged (l
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World's Oldest Rocks Found
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· Score: 5, Informative
As is stated in the New Scientist article, the technique used might actually date the protolith (the material from which this rock formed) and not the actual rock itself. From a geochronologist's stand point, this rock is actually 3.8 billion years old, based on the U-Pb zircon age given in the Science article. The age determination for the reigning oldest rocks discovered was found through U-Pb zircon work. The authors are very clear to point out that this 4.28 Ga date is not a definitely age for the rock.
Gotta love the media jumping head long in front of the science.
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I don't think that was a bug, looks like more of a sign of AI on the browser's part.
Minerals are just like any other chemical species on earth. They react with one another, and form into new and more diverse populations based on a variety of fundamental thermodynamic factors. Since the earth's processes have changed and evolved since planetary accretion, it only makes since that the assemblages of minerals we see on the earth would evolve in much the same way.
It appears that this paper focuses primarily on the biological effects on mineral speciation, but there have been a variety of geologic affects that have had equally profound impacts on the earths mineralogy (which in turns defines the variety of rocks we see). Factors such as the development of the earths core, mantle, and crust, plate tectonics, the development and evolution of our atmosphere and hydrosphere, and then of course the evolution of biota and related biogenic sedimentary rocks are all going to have an effect on the mineralogic evolution of the earth.
There is a process called fission track dating that actually counts the number of paths of alpha particles through the crystal structure (think helium nuclei being shot out into the crystal and leaving destruction in their wake), which represents the number of decays. But this is rarely done in zircon, it is more typical in minerals like apatite, sphene, and micas.
The dating process for zircon used most commonly on this type of rock is called TIMS (thermal ionization mass spectrometry), and this involves crushing a portion of the rock, separating zircon crystals, dissolving them in acid, separating out the U and Pb through a column chemistry process, and then using a TIMS to ionize the U and Pb, and measure the ratio between the different isotopes. Which actually yields 4 different dates for the zicron grain, which can be used to cross check one another.
As is stated in the New Scientist article, the technique used might actually date the protolith (the material from which this rock formed) and not the actual rock itself. From a geochronologist's stand point, this rock is actually 3.8 billion years old, based on the U-Pb zircon age given in the Science article. The age determination for the reigning oldest rocks discovered was found through U-Pb zircon work. The authors are very clear to point out that this 4.28 Ga date is not a definitely age for the rock. Gotta love the media jumping head long in front of the science.