Abstract
Shock veins in the Sixiangkou (L6) chondrite contain two high-pressure assemblages: (i) majorite-pyrope solid solution plus magnesiowüstite that crystallized at high pressures and temperatures from a shock-induced silicate melt of bulk Sixiangkou composition and (ii) ringwoodite plus low-calcium majorite that were produced by solid-state transformation of olivine and low-calcium pyroxene. The morphology and chemistry of the majoritepyrope garnet and the size of the magnesiowüstite crystals indicate a longer duration at high pressure and temperature than predicted by impact scenarios. This pressure-temperature regime is constrained by the olivine-ringwoodite and orthopyroxene-majorite phase transformations, fusion of the meteorite constituents, and crystallization of majorite-pyrope solid solution plus magnesiowüstite from that melt under high pressure.
Original language | English (US) |
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Pages (from-to) | 1570-1573 |
Number of pages | 4 |
Journal | Science |
Volume | 271 |
Issue number | 5255 |
DOIs | |
State | Published - Mar 15 1996 |
Externally published | Yes |
ASJC Scopus subject areas
- General