GRIER(b), A “MONOMICT,” BRECCIATED CHONDRITE

Abstract

The Grier(b), New Mexico meteorite, a single mass of 929.4 grams, was found in 1969. This brecciated chondrite can be classified as an L‐group from the bulk chemical analysis, ∼ 8 wt % metal with an estimated total iron content of 25 wt %, and the constant olivine (Fa25.5) and orthopyroxene (Fs23) compositions. The main portion of the meteorite fits the criteria for an L5 (grey to intermediate hypersthene) chondrite. A conspicuous, large (several cm3) dense fragment, texturally an L6–7 chondrite, contains practically no metal or chondrules. However, there is little variation in the bulk silicate and individual phase compositions between the fragment and the matrix. In spite of this, it seems unlikely that the fragment was created in situ because metal and sulfide are not found in the fragment‐matrix contact zone; thus the formation of olivines and pyroxenes in both parts, as well as the “draining” of metal from the fragment, occurred prior to accretion with little, if any, subsequent thermal metamorphism.

Fluid mobilization of rare earth elements, Th, and U during the terrestrial alteration of H chondrites

“…This is highly consistent with the observations in this study, as limonite is rarely found, and the overall appearance of these samples is not considered to be rusty. Note that Nuevo Mercurio is considered highly porous, which has been confirmed as an unusual feature of this meteorite (Fredriksson et al, 1979).…”

“…Therefore, the positive Ce anomalies and unbound REE depositions with a negative Ce anomaly observed in cracks, that is, type II and III cracks likely result from terrestrial weathering. In the case of Nuevo Mercurio, this meteorite fell as a shower on December 15, 1978, and more than 300 pieces had been recovered when it was officially reported (Fredriksson et al., 1979). In this context, some pieces had ample time to be exposed to the terrestrial environment before the recovery.…”

Glanggang and Selakopi: Two New Paired (?) Indonesian Chondrites

“…as suggested by Neal et al ( /981) for some chondrites. Both of these hypotheses were discussed by Fredriksson et al (1981) to explain the occurrence of a fragment depleted in metal and sulfides in the otherwise homogeneous "Griertb)" chondrite. As in Selakopi and the fragments of Glanggang.…”

Thermochemical Arsenate-Oxide Equilibria in the System Fe–As–O Determined Electrochemically between 317 and 536°C

“…Others, e.g. [18][19][20][21][22][23], then extended the technique to the examination of various sulphate-oxide equilibria. The present study is the first application of the technique to an equilibrium involving the metal oxysalt of a pnictide.…”