Sedimentary rock composed of at least 30 percent rounded to subangular fragments larger
than 2 mm in diameter; typically contains finer grained material in interstices between
larger fragments. If more than 15 percent of the fine grained matrix is of indeterminant
clastic or diagenetic origin and the fabric is matrix supported, may also be categorized
as wackestone. If rock has unsorted or poorly sorted texture with a wide range of
particle sizes, may also be categorized as diamictite.
source
Neuendorf et al. 2005; SLTTs 2004; particle sizes defined from Krumbein phi scale
(W C Krumbein and L L Sloss, Stratigraphy and Sedimentation, 2nd edition, Freeman,
San Francisco, 1963; Krumbein and Pettijohn, 1938, Manual of Sedimentary Petrography:
New York, Appleton Century Co., Inc.)
