Figure F66. Close-up photograph of fragmentation and a subvertical crack that extends from Section 206-1256D-21R-1 (Pieces 16-20), probably opened on a flow top. The crack wall is quenched and fractured in situ, yielding polygonal glass clasts that are displaced away from the wall (Subunit 1256D-4c) (interval 206-1256D-21R-1, 124-142 cm).

Figure F66. Close-up photograph of fragmentation and a subvertical crack that extends from Section 206-1256D-21R-1 (Pieces 16-20), probably opened on a flow top. The crack wall is quenched and fractured in situ, yielding polygonal glass clasts that are displaced away from the wall (Subunit 1256D-4c) (interval 206-1256D-21R-1, 124-142 cm).