| Abstract: | Knudsen cell-quadrupole mass spectrometry has been used to quantitatively determine the composition of the vapor phase produced by heating samples of the Holbrook chondrite to 1300 °C. Maximum observed vapor pressures (atm) of metals are 10?5.3 ± 0.3 Na, 10?5.8 ± 0.3 K, 10?5.3 ± 0.3 Fe, and 10?6.6 ± 0.3 Ni at 1200 °C. S2 (with minor SO2), H2O, and CO2 were also observed in the high-temperature gas phase. Release of intrinsically derived volatiles produced abundant vesicles in the heated sample residues. Some possible implications for chondrite evolution are briefly discussed |
