- a coarse-grained acid igneous rock containing almost twice as much plagioclase as orthoclase: intermediate in composition between granite and diorite
C19: from grano + diorite
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Examples from the Web for granodiorite
From other areas the same materials are present plus sandstone, granite, and granodiorite.The Topanga Culture Final Report on Excavations, 1948
A. E. Treganza
- A coarse-grained igneous rock consisting primarily of quartz, plagioclase, and potassium feldspar, and also containing biotite, hornblende, or pyroxene. It is the coarse-grained equivalent of dacite.
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