Stony meteorite porosities and densities: A review of the data through 2001

Authors

  • D. T. Britt,

    Corresponding author
    1. University of Central Florida, Department of Physics P. O. Box 162385, Orlando, Florida 32816-2385, USA
      *britt@physics.ucf.edu
    Search for more papers by this author
  • G. J. S. J. Consolmagno

    1. Specola Vaticana V-00120, Vatican City State
    2. Vatican Observatory Research Group Steward Observatory, University of Arizona, Tucson, Arizona 85721, USA
    Search for more papers by this author

*britt@physics.ucf.edu

Abstract

Abstract— In this review, we summarize the data published up to December 2001 on the porosity and density of stony meteorites. These data were taken from 925 samples of 454 different meteorites by a variety of techniques. Most meteorites have densities on the order of 3 to 4 g/cm3, with lower densities only for some volatile-rich carbonaceous meteorites and higher densities for stony irons. For the vast majority of stones, porosity data alone cannot distinguish between different meteorite compositions. Average porosities for most meteorite classes are around 10%, though individual samples can range as high as 30% porosity. Unbrecciated basaltic achondrites appear to be systematically less porous unless vesicles are present. The measured density of ordinary chondrites is strongly controlled by the amount of terrestrial weathering the sample has undergone with porosities steadily dropping with exposure to the terrestrial environment. A theoretical grain density based on composition can model “pre-weathered” porosities. The average model porosity for H and LL chondrites is 10%, while L chondrite model porosities average only 6%, a statistically significant difference.

Ancillary