The formation of rocks, especially igneous and metamorphic rocks.
〔地质〕岩石成因
Example sentencesExamples
Most arc magmas have also undergone complex fractionation and contamination paths, which make attempts to quantify their petrogenesis difficult.
The petrogenesis and tectonic setting of the supersuite, and cogenetic felsic volcanic rocks, has been discussed in some detail by Griffin et al..
The petrogenesis of igneous rocks in the Albany-Fraser Province is not well constrained, although U-Pb zircon geochronology establishes that most granitic protoliths were not tectonically reworked Yilgarn Craton.
Some back-arc basalt samples from the East Scotia Sea have high alumina characteristics, suggesting the involvement of subduction-modified mantle sources in their petrogenesis.
Petrogenesis Igneous petrogenesis is the process or set of processes by which igneous rocks are formed.
Derivatives
petrogenetic
adjective
Geology
The Sogneskollen Granitic Complex is Rb-poor while Sr, Ba and NaO show rather large abundances; these have important petrogenetic implications if they represent the magmatic concentrations.
Example sentencesExamples
It thus appears that melting of quartzofeldspathic rocks with greywacke-like bulk composition in the presence of a water-bearing fluid phase may be an appropriate petrogenetic model for the Sogneskollen Granitic Complex.
As for so many cases in the Earth sciences, the igneous geologist has to work back in time using all available field, geochemical, and experimental data to construct a viable petrogenetic history for any particularly igneous rock.
Zircon is an important phase for the petrogenetic interpretation as all the separated grains have rounded, detrital cores with thin euhedral overgrowths.
The revised age for the Jozini Formation rhyolites is also of significance for petrogenetic models proposed for the Karoo silicic magmatism.