melange

melange

, m?lange

Geology a totally disordered mixture of rocks of different shapes, sizes, ages, and origins

Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

mélange

[mā′länzh]

(geology)

A heterogeneous medley or mixture of rock materials; specifically, a mappable body of deformed rocks consisting of a pervasively sheared, fine-grained, commonly pelitic matrix, thoroughly mixed with angular and poorly sorted inclusions of native and exotic tectonic fragments, blocks, or slabs, of diverse origins and geologic ages, that may be as much as several kilometers in length. Also known as block clay.

McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.