L200 Volcanic Breccia

Hand Specimen

Sedimentary textures, very poorly sorted. 
Sub-round to angular grains up to 20mm across. 
Wide variety of clasts: dark purple, cream, rusty orange, grey, several types of lava. 
Some black, shiny igneous crystals. 
Brown-grey matrix of volcanic ash.

Wide range of clasts including
- Basalt
- Slate or phyllite
- Schist
- Chert
- Sandstone
- Carbonate
- Quartz

Matrix of fine volcanic ash.

This is an example of the coarser type of material deposited by explosive volcanic action.

NB,
This is not a typical volcanic breccia, as one usually sees a greater abundance of igneous clasts; other clasts could be wall-rock. Another name for this rock could be “lithic wacke”.

volcanic breccia
lithic wacke