Bul. 502, U. S. Dept. of Agriculture. PLATE Ill. 
Fic. 1.—PRESSURE HAS CAUSED SHEARING ALONG BEDDING PLANES; WHEN EXCAVATED 
THE SHALE COMES OUT IN LARGE FLAKELIKE PIECES. 
Fia. 2.—WHERE PRESSURE HAS BEEN EXTREME, FAULT PLANES HAVE DEVELOPED. 
EFFECTS OF INTENSE PRESSURE ON SHALE. 
