Cryptozoic Ear
“Gaea, mother goddess of Earth, guards her secrets carefully, and with increasing jealousy as they recede in time. The more distant the past, the more likely any records are to have been erased by erosion…” mentions a book about Earth science. The time of origin and the nature of Earth’ first solid surface are uncertain. Much more was learned about the first eon of lunar history during the 1970’s than is yet known of Earth’s, including useful parallels for aspects of earliest Archean evolution. There are many theories of how the planet Earth has been formed, and one of the most popular ones is that Earth formed from a solar nebula as a solid body about 4.6 billion years ago. The meteors kept on crashing into Earth, until finally, between about 4 and 3.8 billion years ago, depending on the source one is looking at, the bombardment gradually stopped leaving the surface of the earth cratered and hot. Due to high temperature, the surface of the earth was melting. This might be one of the explanations to the layered structure of earth’s solid interior.Cryptozoic Eon was an eon during the Archean era, which started about 4 billion years ago, and ended 2.5 billion years ago. During that time, many changes occurred o
The earth’s first atmosphere was probably composed of gases such as helium and hydrogen, which came from the solar nebula from which the solar system supposedly formed, as well as from the asteroid-like bodies that collided to form the Earth. As the Earth heated up from the core foundation, it released gases through volcanoes and other openings. The secondary atmosphere was composed of CO2, methane, nitrogen, and water. A rock record supports this conclusion since it includes carbonates that reflect a carbon dioxide rich atmosphere. Also, one of the greenhouse gases, which are carbon dioxide and methane, must have been present in the atmosphere to prevent the surface from freezing over. If carbon dioxide and methane were very abundant in the Earth’s atmosphere, Archean climates must have been warm, due to greenhouse warming, perhaps reaching 80 degrees C (176 degrees F). The compoents of the heat-conserving greenhouse effect that assured this have been the subject of inconclusive modeling tudies. Possibilities are CO 2, H 2O, and CO far above present levels, plus nitrogen and traces of lesser greenhouse gases. The Archean atmosphere consisted of very little free oxygen because Archean sediments contained some minerals, such as uraninite, that could not have survived in an oxidizing system. Free oxygen remained low enough for ferrous iron oxides (FeO) not only greatly to exceed ferric iron oxides (Fe 2O 3) in the rocks but to be transported in solution. A depletion of C-13 with respect to C-12 in the reduced carbon of these rocks is consistent with (bit does not require) the presence of life by then. Also, ancient soil preserved in rocks contained low contents of oxygen. Changes in the atmosphere at the end of Archean occurred because more volcanoes started to form, and they released gases that were imputed into the atmosphere. There was less carbon dioxide and methane near the surface of the earth. Also, a super continent was formed at the end of the Archean, increasing the area of land available for weathering. The weather extracted carbon dioxide from the atmosphere, and it cooled the atmosphere. In later eras, the super continent was broke up, and plants started reproducing and producing oxygen.
Some topics in this essay:
Protersoic Era,
Possibilities CO,
Earth Volcanic,
,
Venus Jupiter,
Archean Archean,
Archean Era,
Earth Earth,
Wiechert Isotopic,
Northwest Canada,
carbon dioxide,
free oxygen,
earth’s atmosphere,
continental crust,
plates move,
carbon dioxide methane,
plate tectonics,
surface earth,
oceanic plates,
dioxide methane,
little free,
little free oxygen,
plates move faster,
atmosphere little free,
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Approximate Word count = 2200
Approximate Pages = 9 (250 words per page double spaced)
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