microbreccia

microbreccia

[¦mī·krō′brech·ə]
(geology)
A poorly sorted sandstone containing large, angular sand particles in a fine silty or clayey matrix.
References in periodicals archive ?
They contain green, clayey chloritic pellets and various intraclasts representing a poorly cross-bedded microbreccia facies.
Also anomalous on Isle Madame are three long narrow belts of "basement" rocks, together with voluminous chloritic microbreccia and minor semi-ductile mylonite, which are separated from the conglomerate-dominated successions by faults.
The metamorphic basement and/or Glenkeen Formation are everywhere separated from the Carboniferous conglomerate-dominated sedimentary successions by faults, marked by chloritic breccia and microbreccia developed within both metamorphic basement and Glenkeen Formation.