Shock melting

Millbillillie regolith breccia, in plane-polarized light, 2 cm across. Clasts of basaltic eucrite are visible in a crushed matrix, crosscut by a vein of shock-melted material. Image from Lauretta and Killgore (2005), with permission. 

S6 Very strongly shocked Solid-state recrystallization and staining, ringwoodite, melting Shock melted (normal glass) Majorite, melting 75-90... 

Shock melted Whole-rock melting (impact melt rocks and melt breccias) ... 

Ruzicka A., Snyder G. A., and Taylor L. A. (1998) Mega-chondmles and large, igneous-textured clasts in Julesberg (L3) and other ordinary chondrites vapor-fractionation, shock-melting, and chondmle formation. Geochim. Cosmochim. Acta 62, 1419-1442. 

Table 2.2. Chemical compositions (wt%) of starting material and shock melts...

Figure 2.5. BEIs of (a) the samples shocked at 27.4 GPa at room temperature, and (b) shocked at 84.0 GPa at room temperature. There are thin shock melt veins in the 27.4 GPa sample (indicated by arrows), one of which (middle) extends into the brecciated portion (br). Note the presence of remnant eucrite clasts (eucrite ghosts) composed of melted plagioclase and partly melted pyroxene, and veins of mixed-mineral melts (m, left). Light to medium gray pyroxene, dark gray plagioclase (glass), v vesicles.

Figure Z7 Chemical compositions of nonnal shock melts in the sample shocked at 37.6 GPa at loom temperature, and shock partial melts in the 863 °C-preheated sample shocked at 22.8 GPa, normalized to the composition of the starting material. Note that shock partial melts are enriched in FeO and Xi02 and depleted in NaaO and FeO (see text). Error bars give 1 sigma of analyses of melts.

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