Once physicists understood the nature of the atom and realized planets existed without water, they reenvisioned the formless void as an astral explosion. The Big Bang produced the first three elements in the periodic table - hydrogen, helium, and lithium - along with the hydrogen isotope deuterium.
Hydrogen burned to begat helium at temperatures greater than 50,000,000c degrees.
Helium burned to begat carbon and oxygen at temperatures greater than 100,000,000c degrees.
Carbon and oxygen burned to begat the elements up to silicon in the table, including sodium, magnesium and aluminum. The stellar core had contracted and temperatures had risen even more.
Silicon burned to begat the elements up to iron at 1,000,000,000c degrees, then the process stopped. At that point, heat no longer was generated. The production of additional elements would have used energy.
The original elements fell into three categories:
* Gases - hydrogen, helium
* Ices - water, methane, ammonia, nitrogen
* Rocks - magnesium-iron silicates
The ice, gas and dirt were circulating in a circumstellar disk where temperatures were falling. When they reached 700c, the iron began to become magnetic.
When the overall temperature fell into the range of 227c to 527c, the iron-magnesium silicates and iron-nickle began condensing.
Within the next 10,000 years, the small grains were kept buoyant by the gases, and began accumulating through nongravitational electromagnetic forces.
Then, when enough atoms had changed, gravitational forces took over. By the end of a million years, larger clusters (planetesimals) formed into planet embryos, a process that continued until all the material was absorbed into a larger body.
At that point, the gas had been dispersed, and no longer acted as a cushion between the embryos. They began colliding with one another to produce energy (heat) that began melting the material.
At the end of 100 million years the planet was formed, roughly 4,537 million years ago. The segregation of iron from silicon continued to form the core, which was complete about 4,535 million years ago.
Radioactive isotopes like uranium (238U and 235U), thorium (232Th) and potassium (40K) were still in the core. They generated heat each time they underwent a decaying transformation. As the number and kinds of changes decreased, the temperature of the molten mass surrounding the core decreased. With time, it was low enough for parts on the surface to cool into crust.
Heat remained below, so the first crustal elements were unstable - forming, then melting, recycling their component materials. The oldest rocks on earth are recycled fragments of zircon found in Australia from 4,404 million years ago. The oldest in North America are in a greenstone belt near Hudson’s Bay dated to 3,800 million years ago.
The oldest rocks in New Mexico are found in volcanic rocks from Burned Mountain near Hopewell Lake and Gold Hill near Wheeler Peak, and in the greenstone belt near Pecos. Their zircons have been dated to 1,775, 1,750 and 1,720 million years ago.
Notes: Uranium decays to lead. Since zircons contain uranium, but not lead, they are used to date minerals.
Baldridge, W. Scott. Geology of the American Southwest, 2004; gives Pecos greenstone as 1,760 to 1,720 million years.
Daggett, M. Dewitt III. "Precambrian Geology and Metals Potential of the Twining-Gold Hill Area, Taos Range, New Mexico," New Mexico Geological Society Guidebook, 1984; gives Gold Hill as 1,750 million years.
Rollinson, Hugh. Early Earth Systems, 2007. He gives temperatures in Kelvin which are 237 degrees greater than Celsius, a meaningless difference at these temperatures; you could even think of them as Fahrenheit without loss of meaning. New quantities of metals like silver are produced when the right constituent elements are heated again to the right temperatures.
Whitmeyer, Steven J. and Karl E. Karlstrom. "Tectonic Model for the Proterozoic Growth of North America," Geosphere 3:220–259:2007; gives Pecos greenstone as 1,720 million years, and Moppin/Burned Mountain and Gold Hill as 1,770 to 1,750 years old.
Wobus, Reinhard A. "An Overview of the Precambrian Geology of the Tusas Range, North-Central New Mexico," New Mexico Geological Society Guidebook, 1984; gives Moppin/Burned Mountain as 1,775 to 1,725 million years ago.
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