The effects of serpentinization on density and magnetic susceptibility: a petrophysical model Article

Toft, PB, Arkani-Hamed, J, Haggerty, SE. (1990). The effects of serpentinization on density and magnetic susceptibility: a petrophysical model . PHYSICS OF THE EARTH AND PLANETARY INTERIORS, 65(1-2), 137-157. 10.1016/0031-9201(90)90082-9

cited authors

  • Toft, PB; Arkani-Hamed, J; Haggerty, SE

authors

abstract

  • New measurements are presented of initial magnetic susceptibility and density for serpentinized harzburgites from the Josephine Peridotite (Oregon). An inverse correlation between density and susceptibility, which is typical of these rocks and similar rocks from other localities, is not explained by simple serpentinization reactions. Calculations of density and susceptibility as a function of reaction progress for reactions that produce magnetite show susceptibilities that are larger than those observed at low degrees of serpentinization. Susceptibilities of Fe-bearing serpentine and brucite are calculated from a molecular field model initially developed for the olivine and orthopyroxene solid solutions. At high degrees of serpentinization, susceptibilities that are lower than those observed are predicted by reactions where iron is sequestered by serpentine and brucite. Observed density-susceptibility trends of serpentinized harzburgites fall between the values predicted by these limiting reactions. The observed properties may be modelled by multiple reactions involved in multi-stage serpentinization processes such that the production of magnetite increases with the degree of serpentinization. The empirical and calculated properties provide a complementary characterization of density and susceptibility values of serpentinites. © 1990.

publication date

  • January 1, 1990

published in

Digital Object Identifier (DOI)

start page

  • 137

end page

  • 157

volume

  • 65

issue

  • 1-2