QAPF diagram for classification of intrusive igneous rocks, with the monzonite field highlightedPhotomicrograph ofthin section of monzonite (in crosspolarised light)Photomicrograph of thin section of monzonite (in plane polarised light)TheNotch Peak monzonite intrusion inUtah inter-fingers (partly as adike) with highly metamorphosedCambriancarbonate host rocks
Monzonite is a coarse-grained (phaneritic) igneous rock. Such rocks are classified by their relative percentages ofquartz,plagioclase,alkali feldspar, andfeldspathoid (theQAPF classification). Monzonite is defined as rock having less than 5% quartz in its QAPF fraction and in which alkali feldspar makes up between 35% and 65% of the total feldspar content. If quartz constitutes greater than 5% of the QAPF fraction, the rock is termed aquartz monzonite, while if feldspathoids are present as up to 10% of the QAPF fraction, the rock is termed a feldspathoid-bearing monzonite. Rock richer in alkali feldspar is classified assyenite, while rock richer in plagioclase is termed a monzodiorite. Thevolcanic equivalent of monzonite islatite.[2][4]
Diorite, monzonite, and syenite are found together on the margins of thePaleoproterozoicNorth China craton. These likely formed during the assembly ofColumbia and suggest the North China craton was in the interior of Columbia, betweenLaurentia andSiberia.[10]
TheBingham mine consists ofporphyry copper deposits hosted in altered monzonite. Alteration has converted some of the monzonite to compositions resembling quartz monzonite orgranite, by altering plagioclase to potassium feldspar and emplacing hydrothermal quartz.[11]
Fragments of monzonite have been found on the surface of theMoon. These likely formed as a mixture of immiscible granite liquid withcumulates composed of plagioclase andpyroxene, which supports the theory that lunar granites form through silicate liquidimmiscibility. This is a process in which high-silica and low-silica components of a magma separate like oil and vinegar.[12]
Monzonite was originally named after the Monzoni range inVal di Fassa (Trento Province, Italy) where it is abundant. As rock definitions have been systematized and codified, this association has lost any relevance to the rock's definition.[2]
^Allaby, Michael, ed. (2013). "Monzonite".A dictionary of geology and earth sciences (Fourth ed.). Oxford: Oxford University Press.ISBN9780199653065.
^abcdLe Maitre, R.W.,Igneous Rocks: A Classification and Glossary of Terms Cambridge University Press, 2nd ed, pp. 113ISBN0-521-66215-X
^abAndersen, Tom (January 1984). "Crystallization history of a Permian composite monzonite-alkali syenite pluton in the Sande cauldron, Oslo rift, southern Norway".Lithos.17:153–170.doi:10.1016/0024-4937(84)90016-1.
^abKlein, Cornelis and Cornelius S. Hurlbut, Jr.,Manual of Mineralogy, Wiley, 20th ed, pp. 480-484ISBN0-471-80580-7
^Blatt, Harvey; Tracy, Robert J. (1996).Petrology : igneous, sedimentary, and metamorphic (2nd ed.). New York: W.H. Freeman. pp. 52–53.ISBN0716724383.
^Aghazadeh, Mehraj; Castro, Antonio; Omran, Nematallah Rashidnejad; Emami, Mohamad Hashem; Moinvaziri, Hossien; Badrzadeh, Zahra (May 2010). "The gabbro (shoshonitic)–monzonite–granodiorite association of Khankandi pluton, Alborz Mountains, NW Iran".Journal of Asian Earth Sciences.38 (5):199–219.doi:10.1016/j.jseaes.2010.01.002.
^Castro, Antonio; Aghazadeh, Mehraj; Badrzadeh, Zahra; Chichorro, Martim (November 2013). "Late Eocene–Oligocene post-collisional monzonitic intrusions from the Alborz magmatic belt, NW Iran. An example of monzonite magma generation from a metasomatized mantle source".Lithos.180–181:109–127.doi:10.1016/j.lithos.2013.08.003.
^Köksal, Serhat; Toksoy-Köksal, Fatma; Göncüoğlu, M. Cemal; Möller, Andreas; Gerdes, Axel; Frei, Dirk (April 2013). "Crustal source of the Late Cretaceous Satansarı monzonite stock (central Anatolia – Turkey) and its significance for the Alpine geodynamic evolution".Journal of Geodynamics.65:82–93.doi:10.1016/j.jog.2012.06.003.hdl:11511/31761.
^Smith, I. E. M.; White, A. J. R.; Chappell, B. W.; Eggleton, R. A. (May 1988). "Fractionation in a zoned monzonite pluton: Mount Dromedary, southeastern Australia".Geological Magazine.125 (3):273–284.doi:10.1017/S0016756800010219.
^Wang, Wei; Liu, Shuwen; Bai, Xiang; Li, Qiugen; Yang, Pengtao; Zhao, Yue; Zhang, Shuanhong; Guo, Rongrong (March 2013). "Geochemistry and zircon U–Pb–Hf isotopes of the late Paleoproterozoic Jianping diorite–monzonite–syenite suite of the North China Craton: Implications for petrogenesis and geodynamic setting".Lithos.162–163:175–194.doi:10.1016/j.lithos.2013.01.005.
^Lanier, G.; Raab, W. J.; Folsom, R. B.; Cone, S. (1 November 1978). "Alteration of equigranular monzonite, Bingham mining district, Utah".Economic Geology.73 (7):1270–1286.doi:10.2113/gsecongeo.73.7.1270.
^Rutherford, M.J.; Hess, P.C.; Ryerson, F.J.; Campbell, H.W.; Dick, P.A. (1976). "The chemistry, origin and petrogenetic implications of lunar granite and monzonite".7th Lunar Science Conference Proceedings, Houston, Texas. 2. A77-34651 15-91). Pergamon Press, Inc.: 1723-1740.Bibcode:1976LPSC....7.1723R.
