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  • Essay on Banded Iron Formations and Evolution of the Atmosphere

    1273 Words  | 6 Pages

    atmosphere The time between the formation of the earth and the beginning of the Cambrian(about 570mya) is a 4000 my long period known as the Precambrian, this includes approximately 90% of geological time of which we know very little about as pre-Cambrian rocks are poorly exposed, many have been eroded or metamorphosed and fossils are seldom found. The Precambrian has been divided into 3 Eons: 1.Hadean (4600-3800 mya of which there is no rock record) 2.Archean 3800-2500 mya) 3.Proterozoic 2500-570 mya

  • The Geological History Of The Valley

    1435 Words  | 6 Pages

    the valley a great place for geological study (Green, 1997, p. 9). Today’s Death Valley we see has taken millions of years to take its present form. In this paper, we examining the geological history of the valley and its alluvia fan formation. Precambrian and early Phanerozoic Age I. Pre-Cambrian Age In Pre-Cambrian time, Death Valley landscape was much different than what is today. The Pre-Cambrian eon is

  • Evolution Was Introduced By Charles Darwin

    1698 Words  | 7 Pages

    The idea of evolution was introduced by Charles Darwin, and explains how animals change over time. The theory states that every organism on the Earth originated from a common ancestor and then, through the process of natural selection, how those animals branched off to become different organisms. Scholars use this theory to explain how animals that live on Earth change over time. However, scientists find it difficult to use this theory to explain some events that occurred in the geologic time

  • The Precambrian Period

    415 Words  | 2 Pages

    The Earth is 4.5 billion years old. The Precambrian period lasted for 4 billion years. In this era, organic compounds came to earth and formed the first life of single-cell organisms. These single cell organisms evolved into bigger cells and also developed to have a sex. The oxygen levels on earth began to change which leads us into the Cambrian period. The Cambrian period lasted 53 million years and consisted of mostly shallow oceans covering the continents. Skeletons grew in life forms and new

  • Cambrian Period

    2628 Words  | 11 Pages

    Cambrian period 543-490 million years Introduction The Cambrian Period marks the beginning of the Paleozoic Era. This period gets its name from a place in Wales where the first examples of this type of ancient life was found. The period lasted for nearly 53 million years, from about 543 million years ago until 490 million years ago. The Cambrian Period marks an important point in the history of life on earth; it is the time when most of the major groups

  • Precambrian Time

    483 Words  | 2 Pages

    Precambrian Time 4.6 bil.-544 mil. The earth is a Molten Lava World. The earth was formed by countless collisions of meteors/molten rock which made it a world of fire and molten rock. Temp. exceeded 8,000 degrees F radioactivity prevented the molten world from cooling quickly Scientists used radioactive dating to date the Earth.The earth is a Waterworld. Meteors with 5% water help cover the Earth with water, but it was mainly because volcanoes gave of huge amounts of carbon dioxide which formed

  • Precambrian Boundary Essay

    301 Words  | 2 Pages

    The Precambrian boundary today remains a highly controversial topic despite the continuous research and pressures being put on understanding the early Cambrian evolution. Radioactive dating has seen a dramatic advancement as well as continuous progress in chemo-, bio-, and magneto- stratigraphy. Laminated stromatolites prevail in the Precambrian fossil date as well as a completely new perception on ancient life being understood due to the sequence of the chronostratigraphic period. Biosedimentary

  • Precambrian Time Research Paper

    1048 Words  | 5 Pages

    are three main eras.  The three eras are the Paleozoic era, Mesozoic era, and the Cenozoic era. There is also a time which is everything before the eras and it is called Precambrian time. Precambrian time did not have any organisms except for some complex life forms that began to come about nearer to the end of the time. Precambrian time was about 4 billion years long. After that, the Paleozoic era began. The Paleozoic was about 295 years long and

  • The Precambrian Period: The Evolution Of Hard-Shelled Animals

    326 Words  | 2 Pages

    formation of Earth, 4.5 billion years ago till the evolution of hard-shelled animals, about 500 million years ago, is called the Precambrian period. There are many events during this time that are specific and affect the Precambrian life. The earth was formed and the first tectonic plate arose and began to move which caused many variations on the earth conditions during Precambrian that affected atmospheric composition and oceans. The level of oxygen arose in the atmosphere which enabled the enrichment

  • What Is The Purpose Of The Precambrian And Phanerozoic Eras?

    754 Words  | 4 Pages

    language used in the papers is highly academic and technical which would be more suited to an advanced audience or fellow researchers in the field. The map shows the bedrock distribution and type throughout the state, specifically focusing on the Precambrian and Phanerozoic eras. Some of the data is inferred from previous maps with the inclusion of newly discovered types that are indicated as