A QAPF diagram is a doubled-triangle plot diagram used to classify intrusive igneous rocks based on their mineralogy. The acronym QAPF stands for " Quartz, Alkali feldspar, Plagioclase, Feldspathoid (Foid) ", which are the four mineral groups …

IUGS diagram for naming plutonic/phaneritic igneous rocks with An>50. This QAPF diagram is two independent ternary diagrams that share the A-P edge. The upper triangle has the corners A-Q-P, where A is A lkali feldspar, Q is Q uartz, and P is P lagioclase.

QAPF diagram is a double triangle diagram which is used to classify igneous rocks based on mineralogic composition. The acronym, QAPF, stands for "Quartz, Alkali feldspar, Plagioclase, Feldspathoid (Foid)".

Feb 24, 2019 · These diagrams show igneous rock diagrams that the IUGS uses to classify phaneritic and aphanitic igneous rocks.

IUGS diagram for naming volcanic/aphanitic igneous rocks with quartz present. Names are based on the relative modal proportions of quartz (Q), alkali feldspar (A), and plagioclase feldspar (P). Use the Mafic Mineral percentage slider to see the andesite classification change to basalt for rocks with M>35%.

IUGS diagram for naming plutonic/phaneritic igneous rocks with M<90% and with quartz present. This is a combination of the top halves of charts 1a and 1b on one diagram with a plagioclase composition slider.

According to the International Union of Geological Sciences (IUGS), all rocks with a phaneritic, holocrystalline, and coarse-grained texture (> 3 mm) must be classified as plutonic rocks. The classification is centered on the QAPF diagram, developed by Streckeisen (1973). The diagram above is entirely interactive.

WinRock plots IUGS igneous classification diagrams, including QAPF diagrams, plus sandstone, general purpose XY, pie, log, and ternary diagrams. Each diagram contains separate labeled fields corresponding to individual rock types with data and rock names listed in separate tables.

Aug 11, 2023 · A colleague collected some igneous plutonic (coarse-grained/intrusive) rocks (with no feldspathoid) in a field area for a project you are working on. This colleague has plotted the rocks on the ternary diagram below (also known as the IUGS [International Union of Geological Sciences] or Streckheisen diagram) so that you can classify the rocks.

This diagram is an essential tool that allows geologists to determine the mineralogical composition of rocks and classify them into specific groups. The QAPF diagram was developed in the early 20th century by the International Union of Geological Sciences (IUGS).