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Roger Weller, geology instructor

wellerr@cochise.edu


Formation of the Earth
by Blayne Kennedy
Physical Geology
Spring 2009
     
  

Creation of the World:

A Geologic View
 

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            From the beginning of time there has existed matter and energy, and under certain circumstances said matter and energy has formed in many different alterations. In this sense matter has been around for a masses amount of time, and in that time it has evolved to the common elements and masses we know today. This is commonly misunderstood as to other theories, and is also the most scientific theory to prove.
 

            The creation of our solar system was known as the Hadean Eon, this was the time were matter was mainly gasses and dust. This was also the time in which the known plants started to form, however the planets during this time were also extremely hot. The next phase was the Archean Eon, this was mainly where the earth’s crust and overall ground formed. During the late timeframe of this eon early life started to form as well, it consisted of microorganisms. There also was no free oxygen in a matter of fact the organisms that lived during said time would of died if they were present in today’s atmosphere. Also during this time there was no rust seeing as the air consisted of carbon dioxide there were free iron deposits, however there were few stable continents due to major geological changes.

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            Following was the Proterozoic Eon, which started with the earth still hot, and the majority of life being single cell, however over this time the air took radical changes and the earth was hit with an Ice age.  The start of this eon the air was still mainly composed of carbon dioxide and the single cells thrived, soon oxygen sub creating cell evolved and caused the surrounding air to be come more oxygen comprised. This caused many of the organisms that had adapted to the carbon dioxide to die. Also the earth’s iron that was open to the air started to rust and caused much of the rust that is in the dirt today, also during this time the world was mainly covered with water. The iron that did not rust soon formed to be the iron veins we know and mine today. Soon and at the end of the eon an ice age hit the earth and killed off many of the organisms, they left behind much of the organic matter we know today.
 

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            The next eon was the Phanerozoic Eon, this is that eon that we are living in now and is really where life and geologic events took place. At the end of the Proterozoic Eon there where only single cell organisms and a few multi cell organisms.  In the Phanerozoic Eon life evolved and organisms grew larger, plants and other carbon based forms came into existence. These life forms died and produced many of the organic substances we use today such as oil. Another Ice age soon struck and many of the organisms that survived spread to other land masses, after the Ice age the organisms continued to evolve and form the world as we know it today.

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            During most of the eons the earth itself was evolving, in the sense of how the matter and the overall environment. During them the core and also the surrounding earth became exceedingly hot and incredibly cold, this caused minerals and other forms of geological events. The first two eons caused most of the medals to form and then after the air started to shift to a more oxidized zone in the later eons thus causing the metals to decompose and form other forms of matter. The time it took for the earth to cool and heat up at intervals were cultural to the forming of new and different metals and other non-organic matters.
 

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            Also over the eons there were major pressures building up also erupting volcanoes that caused many of them gems and other precious ores or form. In the first two eons there where many more volcanoes this is why we have such and ardency of gems and also why we have such a unique surrounding.
 

Over all the formation of the planet caused everything we know today, all the elements and minerals. The constant heat and pressure, the cool and the factor of life all support how the plant has formed and over all the matter we have is due to these factors.


 

References

http://www.ucmp.berkeley.edu/precambrian/hadean.html

http://www.wisegeek.com/what-is-the-archean-eon.htm

http://www.britannica.com/EBchecked/topic/32681/Archean-Eon

http://geology.about.com/od/fossilstimeevolution/a/precambrian.htm

http://www.wisegeek.com/what-is-the-proterozoic-eon.htm

http://www.britannica.com/EBchecked/topic/479833/Proterozoic-Eon

http://www.wisegeek.com/what-is-the-phanerozoic-eon.htm

http://www.enotes.com/earth-science/phanerozoic-eon

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VN3-49NXMVW-3&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=91ef367251bca2f3bb367af18a8cb8bf

http://www.windows.ucar.edu/tour/link=/earth/Life/first_life.html