@article{oai:nipr.repo.nii.ac.jp:00001106, author = {Matsui, Takafumi and Hamano, Yozo and Honda, Masahiko}, journal = {Memoirs of National Institute of Polar Research. Special issue}, month = {Dec}, note = {P(論文), The intrinsic and bulk densities, porosities and compressional ultrasonic-wave velocities (V_p) in three mutually perpendicular directions have been measured in antarctic meteorites Allan Hills-769 and ALHA77231. V_p measurements were made at the room temperature and under one atmosphere pressure. The intrinsic and bulk densities and porosities are 2.89g/(cm)^3,3.59g/(cm)^3 and 19.4% for the Allan Hills-769 and 3.07g/(cm)^3,3.58g/(cm)^3 and 14.3% for the ALHA77231. The measured velocities were relatively low (the mean values of the three directions were 2.37km/s for the Allan Hills-769 and 3.52km/s for the ALHA77231) and showed up to 4% for the Allan Hills-769 and 10% for the ALHA77231 departures from the mean value of the three directions. The low values of velocity are attributed mainly to the high porosity of the sample. The velocity anisotropy might be due to a difference in crack shape between wavetransmitting directions. The porosity versus petrologic type diagram does not indicate a systematic variation of the porosity with the petrologic type.}, pages = {268--275}, title = {Porosity and Compressional-Wave Velocity Measurement of Antarctic Meteorites}, volume = {17}, year = {1980} }