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branch of geology specifically concerned with the origin, composition, structure, and properties of rocksrock,
aggregation of solid matter composed of one or more of the minerals forming the earth's crust. The scientific study of rocks is called petrology. Rocks are commonly divided, according to their origin, into three major classes—igneous, sedimentary, and metamorphic.
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, primarily igneous and metamorphic, and secondarily sedimentary. It includes petrography, the systematic description and classification of rocks using microscopic examination of rock in thin sections; and petrogenesis, which deals with the origin and formation of the various kinds of rock. Petrology is also concerned with the laboratory simulation of rock-forming processes and the application of principles of physical chemistry to natural environments. Petrologic analyses of oceanic rocks have given insights into plate tectonicplate tectonics,
theory that unifies many of the features and characteristics of continental drift and seafloor spreading into a coherent model and has revolutionized geologists' understanding of continents, ocean basins, mountains, and earth history.
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 processes, especially rock from mid-oceanic ridges, which may be formed from magma derived from deep in the mantlemantle,
portion of the earth's interior lying beneath the crust and above the core. No direct observation of the mantle, or its upper boundary, has been made; its boundaries have been determined solely by abrupt changes in the velocities and character of seismic waves passing
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. Lunar rocks returned by Apollo astronauts were studied with petrographic techniques providing a wealth of information on the makeup and origin of the moon.



the science of rocks. In the USSR, some scientists—for example, F. Iu. Levinson-Lessing and D. S. Beliankin —regard “petrology” and “petrography” as synonyms. According to others, such as A. N. Zavaritskii, petrography deals with just the description of rocks, while petrology is concerned with genetic problems and theoretical constructions based on petrographic descriptions and experimental research.


The branch of geology concerned with the origin, occurrence, structure, and history of rocks, principally igneous and metamorphic rock.
References in periodicals archive ?
and Zellmer, G., 2000, Time scales of crystal fractionation in magma chambers; integrating physical, isotopic and geochemical perspectives: Journal of Petrology, v.
Mineralogy and petrology of the central part of the Hindu Bagh Igneous complex, Hindu Bagh Mining District, Zhob Valley.
The petrology of the Warsak alkaline granites, Pakistan and their relationship to other alkaline rocks of the region.
and Carbno, G.M., 2003, Petrology and U-Pb geochronology of lower crustal xenoliths and the development of a craton, Slave province, Canada: Lithos, v.
Detrital modes of the sandstones and petrology of the conglomerates show that the detritus for the Neogene succession has mainly been derived from the Pre-Miocene sedimentary and meta- sedimentary terrains of the Pishin Belt from the west, which include Eocene Nisai Formation and Oligocene Khojak Formation; and Sulaiman Belt from the east, which include Triassic Wulgai Formation, Jurassic Loralai Formation and Cretaceous Parh Limestone.
Archer is pleased to announce today petrology results for four additional locations on two tenements directly east and southeast of its main Cleve area graphite projects at Sugarloaf, Campoona, Campoona South and Council Pit.
Chapters are in sections on spontaneous combustion and greenhouse gases, mineralogy and petrology, geophysics and modeling, geophysics and remote sensing, and coal fires and public policy.
The book is divided into 5 different sections: mineralogy and crystal chemistry, petrology, biomineralization, geochronology, and materials application.
Petrology of these sandstones was studied and modal analysis carried out in order to classify and understand their detrital modes and provenance.
This paper is restricted to the ultramafic rocks in terms of their petrology and mineralogy.