Qapf Rock Diagram. These are the mineral groups used for classification in qapf diagram. The acronym qapf stands for quartz alkali feldspar plagioclase feldspathoid foid.
A qapf diagram is a double triangle diagram which is used to classify igneous rocks based on mineralogic composition. Explanation of the qapf diagram used to classify igneous rocks. It is made of two ternary diagram s with the corners q a p and f a p adjoined to each other along their a p edge.
Explanation of the qapf diagram used to classify igneous rocks.
The acronym qapf stands for quartz alkali feldspar plagioclase feldspathoid foid. But after posting it on few social platforms i realized that people naturally miss mafic minerals when they see granite diorite or any other especially gabbro. The diagram was created by the subcommission of the systematics of igneous rocks in the latter part of the 20th century. The qapf diagram the chapter quartz as a rock forming mineralintroduced the qapf diagram as a means to visualize and memorize the classification of igneous rocks based on their content of the minerals quartz alkali feldspar plagioclase and foids.
