Classification of Igneous Rock Series
@article{Peacock1931ClassificationOI, title={Classification of Igneous Rock Series}, author={Martin A. Peacock}, journal={The Journal of Geology}, year={1931}, volume={39}, pages={54 - 67} }
Some rock series cannot be properly classified either as alkalic or as sub-alkalic. To meet this situation a simple extension of the present twofold classification is proposed; this takes the form of a fourfold division into alkalic, alkali-calcic, calc-alkalic, and calcic groups. It is shown, from a partial graphical representation of thirteen rock series, that the silica value at which the curves for total alkalis and for lime intersect (the alkali-lime index) is characteristic of a rock…
453 Citations
7.3 Classification of Igneous Rocks
- Geology
- 2019
As has already been described, igneous rocks are classified into four categories, based on either their chemistry or their mineral composition: felsic, intermediate, mafic, and ultramafic. The…
A chemical–mineralogical classification of common plutonic rocks and associations
- Geology
- 1983
A classification is proposed, based mainly on major element analytical data plotted in a coherent set of three simple chemical-mineralogical diagrams. The procedure follows two complementary steps at…
A Geochemical Classification for Feldspathic Igneous Rocks
- Geology
- 2008
In this paper we classify the range of feldspathic igneous rocks using five geochemical variables: the FeO/(FeO þMgO) ratio or Fe-index, the modified alkali^lime index, the aluminum-saturation index,…
What Is the "Calc-alkaline Rock Series"?
- Geology
- 2002
The "calc-alkaline" series of rocks was originally defined in the early 1930s on the basis of the "alkali-lime index" on a combined SiO2 versus (Na2O + K2O) and SiO2 versus CaO plot. The usage of the…
Chemical variation, modal composition and classification of granitoids
- GeologySpecial Publications
- 2020
Abstract Granites (sensu lato) come in many types and flavours, defining distinct magmatic series/suites/types. A good classification not only gives generally accepted and understandable names to…
Classification of fine-grained igneous, sedimentary and metamorphic rocks through structured programming
- Geology
- 2014
The study of rocks has become more important, because through the rocks analysis I can be obtained information that can be useful in a lot of fields from mining to construction, passing through many…
Use and Abuse of the Terms Calcalkaline and Calcalkalic
- Geology
- 2003
The terms calcalkaline and calcalkalic are currently defined and used in multiple and non-equivalent ways. Generally, the variation of total Fe as FeO/MgO within evolving subalkaline rock suites is…
The petrology and geochemistry of intrusive alkaline rocks of Elchuru, Prakasam District, Andhra Pradesh, India
- Geology
- 2007
The Elchuru alkaline igneous intrusion is an arcuate-shaped ring complex, approximately 16 km2 in area, cropping out in the Eastern Ghats high grade metamorphic series. It is part of an alkaline…
References
SHOWING 1-2 OF 2 REFERENCES
Igneous Rocks and their Origin
- GeologyNature
- 1914
PROF. DALY is a man of ideas. A few facts observed in the field suggest to him a hypothesis which he then proceeds to test by searching for other facts which must exist if the hypothesis be of any…
On the Origin of the Alkaline Rocks
- GeologyThe Journal of Geology
- 1928
The writer believes that the process of albitization, now known to be a common accompanying feature of granitic intrusion, furnishes a key to the genesis of alkaline rocks. The passage of emanations…