Earth Science Frontiers ›› 2015, Vol. 22 ›› Issue (6): 1-9.DOI: doi: 10.13745/j.esf.2015.06.001

• Article • Previous Articles     Next Articles

Precambrian geodynamics (Ⅰ): From universal environment to protoEarth.

  

  1. 1. College of Marine Geosciences, Ocean University of China, Qingdao 266100, China
    2. Key Lab of Submarine Geosciences and Prospecting Techniques, Ministry of Education, Qingdao 266100, China
    3. Department of Geology, Northwest University, Xian 710069, China
  • Received:2015-05-30 Revised:2015-07-22 Online:2015-11-15 Published:2015-11-25

Abstract:

The origin of everything is the eternal theme of natural science and scientific research in frontier. Modern natural science in the promotion of keeping pace with the sophisticated technology continuously accumulated many new discoveries, very much new knowledge and new theories in recent 100 years. The exploration of origin to everything is no longer confined to an exploration stage of a single phenomenon, and is at the cognitive age of interdisciplinary research for the unified origin of all things origin. This paper systematically integrates these advances to the Earthrelated origins, especially in the recent 10 years, from the professional popularization perspective. Focusing on the origins of large phenomena in the establishment of astronomy theory as the main line, this paper describes concisely the origins of the universal, elements, star, protoEarth and others. The latest studies suggest that the universe originates from the Big Bang at 13.7 billion years ago and the spatial expanding rate is faster than the speed of light; thus the cosmic inflation theory has become the recent advance of the Big Bang theory. At 10-35s after the Big Bang the primitive “superforces” starts to break up due to spontaneous broken, and strong nuclear force, electroweak force and gravitational force are generated, meanwhile Deuteriumtype and Heliumtype stable atoms starts to turn up. At 10-34s the universe is still small which is only comparable with the presentday solar system, but its temperature has dropped to 1027K and the nuclear force isolates from the other two forces, the universe finished its expanding period and turned into standard Friedman expansion period. The plasma entropy of the freequarks and gluon and lepton constitute the universe; the concentrations of the free quarks produce protons and neutrons; matter annihilated with antimatter but exceeded by about one billionth part. The primitive universe was glutted with different microscopic particles and elements were originated from the collision and fusion of these particles, and the formation of elements are considered to have undergone 8 stages. After one billion years since the Big Bang, the universe went into the stage of star condensation; the temperature of the universe dropped to 18 K and the first galaxy and star appeared; the vast clouds of the galaxy dust and gas in the galaxy were condensed to form stars. The latest “Zero Time” of the solar system derived from U - Pb method is 4567±1 Ma. It takes about 9 billion years from the initiation of the universe to the formation of the solar system. Hundreds of generations of the explosion of the big stars may have occurred. The modern nebular hypothesis proposes that the formation of the protoEarth begins with embryo of a planet which is the assemblage of the planetesimals, and then the embryo gradually accreted to about more than 1/2 of the present day Earth at 4550 Ma. Then the Earths protocore appeared at about 4530 Ma. The relatively cold primary planet embryo became warmer and warmer due to the effects of impact, compression and radioactive decay processes, the protoEarth continuously generated heat accumulation and global developing process started. In summary, the paper briefly introduces the essences and frontiers of many academic achievements for both to popularly satisfy the lovers of natural science and to help professional experts profoundly understand different fields of scientific frontiers and new achievements.

Key words: universal origin, Earth origin, element origin, star origin, Precambrian

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