Japan Geoscience Union Meeting 2015

Presentation information

Oral

Symbol P (Space and Planetary Sciences) » P-PS Planetary Sciences

[P-PS21] Planetary Sciences

Sun. May 24, 2015 9:00 AM - 10:45 AM A02 (APA HOTEL&RESORT TOKYO BAY MAKUHARI)

Convener:*Kosuke Kurosawa(Planetary Exploration Research Center, Chiba Institute of Technology), Keiko Hamano(Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo), Chair:Keiko Hamano(Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo), Kosuke Kurosawa(Planetary Exploration Research Center, Chiba Institute of Technology)

10:30 AM - 10:33 AM

[PPS21-P01] Fracture process inferred from fragment shape in impact disruption

3-min talk in an oral session

*Toshihiko KADONO1, Takayuki TANIGAWA1, Hitoshi MIZUTANI2 (1.University of Occupational and Environmental Health, 2.Newton Press)

Keywords:impact, disruption, fragment shape, fracture process

The results of the previous impact experiments show that the shape of the fragments, characterized by the triaxial dimensions a, b, and c, (a ? b ? c), behaves in a very regular way (e.g., Fujiwara et al. 1989). In widely different experimental conditions, the axial ratios, b/a and c/a, have distributions peaked at about each mean value, ~ 0.7 and ~ 0.5, respectively, and flattened (i.e., small c/a) fragments are almost absence.
We find that, if the distribution of the shape parameters, (b/a, c/a), is homogeneous, and there is no fragment at c?? < k, where k is a constant (0 < k < 1; in Fujiwara et al. (1978) k was ~ 0.2), the averages of the shape parameters, (0.7, 0.5) can be realized. Then, we discuss the fracture processes to represent the homogeneous distribution in the shape parameters. The expected dominant fracture process in impact fragmentation is reported.
Fujiwara, A., et al., Nature 272, 602-603, 1978.
Fujiwara, A., et al., in Asteroids II, pp. 240-265, 1989.