JpGU-AGU Joint Meeting 2017

Presentation information

[EE] Poster

B (Biogeosciences) » B-AO Astrobiology & the Origin of Life

[B-AO01] [EE] Astrobiology: Origins, Evolution, Distribution of Life

Wed. May 24, 2017 10:45 AM - 12:15 PM Poster Hall (International Exhibition Hall HALL7)

convener:Kensei Kobayashi(Department of Chemistry and Biotechnology, Faculty of Engineering, Yokohama National University), Masatoshi Ohishi(Astronomy Data Center, National Astronomical Observatory of Japan), Hikaru Yabuta(Hiroshima University, Department of Earth and Planetary Systems Science), Joseph Kirschvink(Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA)

[BAO01-P13] Validation on the spiral microstructure formed at interface of the carbonated water in early Earth

*Shinji Karasawa1 (1.Miyagi National College of Tecnology Professor emeritus)

Keywords:Spiral structure, Early Earth, Carbonated water, Crystal growth of ice, α-quartz

The first stage of molecular bio-history progressed by interactions between the system of intermolecular bonding and the environment. Membrane at interface of water became robust by carbohydrates. Carbohydrates were made from moleules of CO2 and H2O. Atmosphere of primitive Earth was comprised of CO2 and H2O. Solubility of CO2 in liquid water under the high pressure is large. From evaluation of Henry's law, 40 bar of CO2 on initial Earth corresponds with 105 times of 0.0004 bar on today's CO2. However, molecule of CO2 is soluble in water at only low temperature. 98.3% of the CO2 in carbonated water is linear molecule. The linear molecule of CO2 will be incorporated in the through-hole of three-dimensional structure of liquid water as follows.
The molecule of water is described as slightly distorted tetrahedron of sp3-hybridized four orbitals. Two of short O-H bond lengths are associated with covalent bond. Two of long O--H bond lengths are associated with ionic bond. Crystal of ice is usually hexagonal structure (1h: P63/mmc 194). There is spiral alignment, although there exist glide planes alternately in P63/mmc structure. The hexagonal symmetry is formed by a spiral alignment. That is, short side of tetrahedron and long side are connected alternately by 3 direction of electric coupling force. So, the growth of ice is much faster at the {100} interface than at the {111} interface [1].
The microstructure of H2O molecules is formed basing on the plane of interface. There is a space of through-hole in the center of each spiral structure. Linier CO2 molecule will be inserted to the through-hole, and the spiral structure is rearranged by its flexibility. It is confirmed that lattice structure of α-quartz is an optimum model to represent the microstructure of carbonated water formed at the plane interface [2].
[1] Nada,H., (2009), J. Physical Chemistry B, 113 (2009) 4790-4798.
[2] Karasawa, S., (2016), https://youtu.be/_KRvJ5cClDk