Impact breccia in lapillistone matrix Impact breccia in lapillistone matrix. – Rubielos de la Cérida impact basin (Spain) near Olalla. Muschelkalk breccia-within-breccia, lapillistone matrix (accretionary lapilli). Related Posts:Impact breccia generations Crooked CreekCrooked Creek Breccia KopieNew Article_ Pingos, Mardels and Meteorite Impact…Shedding new light on the Wyoming impact crater strewn fieldDirty science: The possible Almería (Spain) impact structure