Journal of Petrology

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Journal of Petrology | Volume 44 | Number 5 | Pages 929-935 | 2003
© Oxford University Press 2003

Use and Abuse of the Terms Calcalkaline and Calcalkalic

RICHARD J. ARCULUS^*

DEPARTMENT OF GEOLOGY, AUSTRALIAN NATIONAL UNIVERSITY, CANBERRA, ACT 0200, AUSTRALIA

Telephone: 61 2 6125 2056. Fax: 61 2 6125 5544. E-mail: Richard.Arculus{at}anu.edu.au

RECEIVED NOVEMBER 18, 2002; ACCEPTED NOVEMBER 29, 2002

	ABSTRACT

TOP ABSTRACT INTRODUCTION THE PROBLEM A PROPOSAL SOME EXAMPLES AND COMMENTS SUMMARY REFERENCES

 
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 regarded as the most distinctive character of calcalkaline compared with tholeiitic suites, reflecting the relative timing of phase saturation with Fe–Ti oxides, plagioclase, and ferromagnesian silicates. Other classification schemes are widely used, including a minority of adherents to the original formalized definition of ‘calcalkalic’ by Peacock (1931, Journal of Geology 39, 54–67). Given the prevailing contradictory and confusing usage of these terms, which leads to miscommunication, it is proposed that the spectrum of subalkaline rocks be divided into high-, medium-, and low-Fe suites, complementing divisions made on the basis of K contents. The terms calcalkaline and calcalkalic should be restricted to rock suites that conform to Peacock's definition.

KEY WORDS: calcalkaline; calcalkalic; subalkaline; tholeiitic; rock classification

	INTRODUCTION

TOP ABSTRACT INTRODUCTION THE PROBLEM A PROPOSAL SOME EXAMPLES AND COMMENTS SUMMARY REFERENCES

 
The etymology of the interchangeable (and variably hyphenated) terms calcalkaline and calcalkalic stems from the late 19th century (Harker, 1909, p. 90). A fundamental division between alkaline and subalkaline rocks had been recognized (e.g. Iddings, 1892), and a degree of competition prevailed between chemical and geographical distinctions, wherein Harker's ‘Atlantic-branch’ corresponded to alkaline and ‘Pacific-branch’ to subalkaline. This fundamental distinction persists in the current International Union of Geological Sciences' classification scheme involving the ‘total alkalis vs SiO₂’ (TAS) diagram (Le Bas et al., 1986), in recognition of the linkage between a discriminant line in total alkalis vs SiO₂ space and the low-pressure thermal divide between critically SiO₂-undersaturated and -saturated rock types (e.g. Yoder & Tilley, 1962). The subalkaline types were also recognized by early 20th-century petrologists as being richer in CaO (lime) at a given SiO₂ content than the alkaline types, so that the adjective ‘calcalkali’ was applied to some subalkaline series (e.g. Holmes, 1918).

Within the spectrum of volcanic rock series, Peacock (1931) formalized the term ‘calc-alkalic’ as one of several that can be applied to a specific group of rocks because he believed that the relations of total alkalis to lime (hence ‘alkali–lime index’) were fundamental in defining the feldspar compositions (readily determinable with a petrological microscope), and in themselves vital for rock classification. The terms used by Peacock (alkalic, alkali-calcic, calc-alkalic, and calcic) were applied to suites of rocks, not individual samples, and were based on arbitrary divisions drawn on a combined plot of total alkalis (wt % Na₂O + K₂O) and lime (wt % CaO) vs silica (SiO₂). Relative to SiO₂, CaO and (Na₂O + K₂O) show contrasting variation—CaO decreases with increasing SiO₂ and (Na₂O + K₂O) increases. Consequently, for any given suite, the lines of best fit through the lime and total alkali data arrays on a combined silica variation diagram intersect at a particular SiO₂ value, determined by how alkalic or calcic a particular suite happens to be (see Fig. 1). For calcalkaline rocks, the intersection between best-fit lines of lime and alkalis was defined to occur between 56 and 61 wt % SiO₂. It is noteworthy that the only examples among individual volcanic suites that were accordingly classified as calcalkaline, and the immediate object of Peacock's own research, were from Iceland, an area we currently recognize as resulting from plume–ridge interaction. In contrast, volcanic suites from Katmai (Alaskan island arc) and Lassen Peak (southern Cascades arc) were classified as calcic. Similarly, Hatch et al. (1961, p. 337) commented: ‘Because they belong to the alkali suite the typical olivine basalts of Hawaii and elsewhere are now distinguished as alkali olivine basalts, although such rocks are among the most typically calcalkaline in composition.’ The important historical point is that within the spectrum of volcanic rock suites, application of Peacock's ‘alkali–lime index’ resulted in the equating of calcic with most subalkaline.

View larger version (30K): [in this window] [in a new window]   Fig. 1. Variations of wt % CaO and Na2O + K2O vs wt % SiO2 for bulk-rock compositions (major oxides, volatile-free, normalized to 100% totals) from the volcanic front of the NE Honshu (Japan) arc. Original named fields within wt % SiO2 ranges are from Peacock (1931) and are applied to suites whose oxide variation trends intersect within a given field.

 
The first half of the 20th century was also marked by a debate concerning variation of relative concentration of Fe oxides within the spectrum of subalkaline rock series [see Young (1998) for review]. The marked Fe enrichments in evolving subalkaline magmas advocated by Fenner (1929) and established by Wager & Deer (1939) for the Skaergaard intrusion brought into focus the possibility of differing trends of compositional evolution for subalkaline suites. E. F. Osborn and colleagues established experimentally the important role of oxygen fugacity (f_O2) in controlling the timing of appearance in a given crystallization sequence of Fe–Ti oxides (e.g. Osborn, 1959), which in turn determines the level of Fe enrichment in a particular suite. The important role of H₂O in the relative retardation (and shift to more anorthitic compositions) of plagioclase saturation in subalkaline melts has also been recognized as critical in the development of contrasted trends of Fe-enrichment (Grove & Kinzler, 1986). For many petrologists, variations in relative Fe concentration in evolving subalkaline suites, and the potential ultimate control of this characteristic by f_O2 and H₂O variations, has become the most important initial classificatory parameter for distinguishing so-called tholeiitic from calcalkaline suites.

	THE PROBLEM

TOP ABSTRACT INTRODUCTION THE PROBLEM A PROPOSAL SOME EXAMPLES AND COMMENTS SUMMARY REFERENCES

 
Petrologists and geochemists are collectively in trouble with the use of the term calcalkaline (or calcalkalic) because:

1. the continued use of Peacock's formalized definition has only been retained to any extent by granite petrologists. Despite this usage pattern, many glossaries (such as those published by the American Geological Institute) retain the Peacock (1931) definition. Similarly, in the recently published Oxford Companion to the Earth (Hancock et al., 2000, p. 557), it is asserted that ‘calcalkaline magmas...contain relatively large amounts of calcium (CaO) in relation to alkalis (Na₂O and K₂O)’. In a complementary way, a number of dictionaries (e.g. that published by Penguin) of geological terms state that calc-alkali is to be ‘applied to igneous rocks in which the dominant feldspar is calcium-rich’, and that ‘the converse of calc-alkali is alkali’, whereas others (published by Collins) use a combination of the Wilkinson (1968) and Irvine & Baragar (1971) definitions (see below).
   
2. Nevertheless, the majority of geochemists and petrologists currently engaged in studies of volcanic rocks having employed the discriminant in the TAS diagram to first distinguish between subalkaline and alkaline series, then employ either Miyashiro's (1974) arbitrary discriminant based on total Fe as FeO (i.e. FeO*)/MgO vs wt % SiO₂, or Kuno's (1968) discriminant boundaries in an (Na₂O + K₂O) vs FeO* vs MgO (AFM) diagram, to distinguish between tholeiitic and calcalkaline rocks. Another less popular discriminant between tholeiitic and calcalkaline series is that proposed by Irvine & Baragar (1971) on the basis of wt % Al₂O₃ vs normative plagioclase composition, wherein the tendency towards higher Al₂O₃ contents of subalkaline magmas erupted in arc settings (as a consequence of delayed plagioclase saturation) is emphasized. It should be noted that ‘lime’ (or ‘calc’) does not feature directly in any of the TAS, FeO*/MgO vs wt % SiO₂, AFM diagrams, and Irvine & Baragar discriminant, and alkalis are not involved directly in the FeO*/MgO vs wt % SiO₂ diagram.
   
3. Calcalkaline has also become synonymous in many geologists' minds variously with: (i) medium-K (as opposed to low-K = tholeiitic, or high-K = shoshonitic/alkalic) volcanic rock series (see Rollinson, 1993, p. 56); (ii) derivative from high-Al basalt rather than ‘low-Al = tholeiitic’ (see Wilkinson, 1968); (iii) ‘hypersthenic’ as opposed to ‘pigeonitic’ rock series (associated with low-K tholeiitic parental basalts) (e.g. Kuno, 1968); or even (iv), light (L) rare earth element (REE)-enriched compared with heavy (H) REE, in contrast to tholeiitic series characterized by low LREE/HREE.
   
4. Rock series that are claimed to be calcalkaline by one of these discriminants cannot necessarily be classified as such using any of the other discriminants (e.g. Kersting & Arculus, 1994).
   
5. Wherever calcalkaline rocks are commonly identified by any one of the non-equivalent classification schemes in use, it is assumed that the rocks must have formed in an island or continental arc setting.
   
6. Whenever the same term is being used to describe objects that, in reality, differ from one another in definable, different, and interesting ways then we have a clear scientific problem, and communication between scientists inevitably will be at cross-purposes. The problem is not quarantined within petrology and geochemistry, as workers in other fields such as tectonics and geophysics inherit the classificatory mess.
   

The purpose of igneous rock classification is to identify distinctive members of the compositional spectrum, and to establish bounding parameters that help focus genetic theories for particular rock types. The inevitable redundancy of classification schemes that are based on genetic models has persuaded most workers to persist with directly measurable parameters, even if the majority of the field boundaries are arbitrary and simply geometrically or mathematically convenient, as for example in the TAS classification diagram (e.g. Streckeisen, 1976; Le Bas et al., 1986). It should be noted, however, that the discriminant between alkaline and subalkaline rocks in the TAS diagram has particular significance because many volcanic suites of distinctive geochemical and mineralogical composition clearly diverge from the discriminant boundary (rather than crossing or straddling it), and the position of the boundary in wt % (Na₂O + K₂O) vs SiO₂ space results from the projection in this compositional space of the relatively low-pressure (10⁵ Pa to 1 GPa) thermal divide corresponding to the stability of olivine–clinopyroxene–plagioclase that separates melts that fractionate to feldspathoid-normative from hypersthene- and ultimately quartz-normative compositions, respectively.

	A PROPOSAL

TOP ABSTRACT INTRODUCTION THE PROBLEM A PROPOSAL SOME EXAMPLES AND COMMENTS SUMMARY REFERENCES

 
Within the realm of subalkaline rocks, it has proven particularly useful to distinguish suites characterized by two major compositional parameters: (1) the abundance of K (or its oxide) vs SiO₂ content, reflecting a combination of initial petrogeneses and evolutionary processes (Gill, 1981); (2) the degree of Fe-enrichment at equivalent SiO₂ contents or some other measure of magmatic evolution (e.g. Carmichael, 1964; Osborn, 1979). The key factors controlling this latter variability are the independent variables of H₂O concentration, which controls the timing of phase appearance of plagioclase compared with ferromagnesian minerals, and oxidation state (controlling inter alia the appearance and persistence of a spinel phase in the compositional range Al-bearing chromite to magnetite, the solubility of S, and sulphide/sulphate stability; O'Neill & Mavrogenes, 2002).

It has not yet been established that any single physico-chemical equivalent of the olivine–clinopyroxene–plagioclase low-pressure thermal divide exists to separate high- from low-FeO*/MgO rock suites. Although saturation with an Fe–Ti oxide phase leads to marked changes in the individual trends of volcanic suites on an FeO*/MgO vs wt % SiO₂ type of diagram (Osborn, 1979), overall in many island and continental arcs, a scatter of data across the Miyashiro (1974) discriminant line exists (see Gill, 1981, p. 4). We should assume for the present that a continuum exists.

Granted the usefulness of distinguishing independently of the K₂O vs SiO₂ character the variations of FeO*/MgO (at specific fractionation variable), I propose, first, that we restrict the use of the term calcalkaline to only those suites that conform to Peacock's original criterion, and, second, that we adopt new terms such as ‘low-, medium- and high-FeO*/MgO’ (possibly abbreviated to loFe, meFe and hiFe, respectively) for ‘subalkaline’ suites (established by the TAS discriminant), based on arbitrary divisions of the natural compositional spectrum (see below). I suspect that the term tholeiite is too deeply embedded within the reflexive terminology of petrologists to abandon [see Chayes (1965) for a critique of this word], but in essence, the hiFe suite of subalkaline rocks would be equivalent to tholeiitic suites. It is illogical and uninformative to continue to use the term calcalkaline for rock suites where the defining characteristics are based neither on ‘calc’ nor ‘alkaline’, and where the multiplicity of definitions in use hinders scientific exchange.

	SOME EXAMPLES AND COMMENTS

TOP ABSTRACT INTRODUCTION THE PROBLEM A PROPOSAL SOME EXAMPLES AND COMMENTS SUMMARY REFERENCES

 
It is instructive to examine some examples of the correspondence of representative volcanic arc suites to existing criteria for distinguishing calcalkaline suites. In Fig. 1, the variations of wt % CaO and Na₂O + K₂O vs SiO₂ for samples collected along the volcanic front from the northern Izu arc through NE Honshu (Gust et al., 1997) are shown relative to the Peacock (1931) discriminants. Although multiple suites are present [including the type ‘pigeonitic’ and hypersthenic' series described by Kuno (1950) for Hakone], very few of these suites could be classified as calcalkaline on the basis of the relevant discriminant boundary; the bulk of the suites are calcic in Peacock's terms. Compositional data for the same sample set are plotted in an AFM diagram in Fig. 2 and FeO*/MgO vs wt % SiO₂ in Fig. 3 (together with an example of a type tholeiitic suite from Thingmuli, Iceland); Kuno's (1968) and Miyashiro's (1974) discriminant boundaries between tholeiitic and calcalkalic rocks are shown in Figs 2 and 3, respectively. A clear bimodality can be seen in both Figs 2 and 3; fewer rocks are classified as tholeiitic by the AFM discriminant boundary compared with that in FeO*/MgO vs wt % SiO₂ space. In addition, the compositional gap between these NE Honshu suites does not correspond neatly to either of Kuno's or Miyashiro's discriminant boundaries.

View larger version (29K): [in this window] [in a new window]   Fig. 2. Bulk-rock compositions from the volcanic front of the NE Honshu (Japan) arc projected in terms of wt % (Na2O + K2O) vs total Fe as wt % FeO (FeO*) vs wt % MgO (AFM). The discriminant boundary between tholeiitic and calcalkalic is from Kuno (1968).

 

View larger version (29K): [in this window] [in a new window]   Fig. 3. Bulk-rock compositions from the volcanic front of the NE Honshu (Japan) arc () and Thingmuli volcano in Iceland from Carmichael (1964) () projected in terms of FeO*/MgO vs wt % SiO2 (major oxides, volatile-free, normalized to 100% totals). The discriminant boundary (fine line) between tholeiitic and calcalkalic (italicized) suites is from Miyashiro (1974). Coordinates for the proposed discriminant boundaries (bold lines) between low-, medium-, and high-Fe suites in FeO*/MgO vs wt % SiO2 space are: wt % SiO2 50 52·5 55 57·5 60 62·5 65 67·5 70 FeO*/MgOhigh-medium 1·20 2·25 2·85 3·32 3·67 3·95 4·24 4·50 4·80 FeO*/MgOmedium-low 0·90 1·30 1·65 1·90 2·20 2·40 2·65 2·85 3·00 Third-order polynomial and logarithmic best-fit curves through these coordinates for the high–medium and medium–low discriminant boundaries, respectively, within the ranges of 50–70 wt % SiO2 (S) are: FeO*/MgO = -154·45 + 7·2672S - 0·11245S2 + 0·000587S3, and FeO*/MgO = -23·255 + 14·277 log S, with correlation coefficients of 0·99945 and 0·9966, respectively.

 
I have placed arbitrary discriminant boundaries between the proposed low-, medium-, and high-Fe fields respectively in Fig. 3, superimposed on the NE Honshu data. Despite the convenience of straight lines, I suggest the discriminant boundaries should curve to parallel the decrease in rate of FeO* increase as a function of SiO₂ content, given the observed compositional effects in residual melts that saturation with, and fractional crystallization of, Fe–Ti oxides have in well-characterized rock suites. The values of FeO*/MgO at specific wt % SiO₂ contents for the proposed high–medium and medium–low FeO*/MgO vs SiO₂ boundaries are given in the figure caption.

These boundaries have been drawn as far as possible to ensure that various suites currently asserted to be dominantly formed by fractional crystallization remain within a given field. Thus, for example, the Thingmuli suite of Carmichael (1964) and the pigeonitic series of Kuno (1950) both fall within the high-Fe field, whereas Kuno's hypersthenic series falls within the medium-Fe field. Although it is not my purpose here to pursue petrogenetic aspects governing the diversity of these suites, it is worth noting that among possible interpretations of the clustering of some of the Honshu data in the medium-Fe field are that it results from phenocryst (plagioclase, clino- and orthopyroxene) accumulation and/or mixing processes, fractionation at higher pressures and/or H₂O contents (e.g. Grove et al., 1982). Usage of the names pigeonitic and hypersthenic has not been globally useful because of the paucity or absence of the latter phase from many arc suites. In the case of Mt. Fuji [dominated by basaltic lavas erupted from a recharged–tapped–fractionated magma chamber (Arculus et al., 1991)], Miyashiro's original boundary between calcalkalic and tholeiitic is transgressed, with the more evolved lavas being tholeiitic and the lower FeO*/MgO (i.e. more primitive) lavas being classified as calcalkalic. The compositional spread of the basaltic lavas of Klyuchevskoy (the world's most active island arc volcano) is similar (Kersting & Arculus, 1994).

In fact, there is accumulating evidence for the importance of selective crystal accumulation in island arc lavas and deviation of the major element compositions of these rocks from genuine melts (Crawford et al., 1987). One of the consequences of the delayed appearance of plagioclase in relatively H₂O-rich magmas is the consequent enrichment in alkalis and alumina in the residual melts, and the formation of genuinely high-Al liquids. However, the absolute degree of alumina enrichment in hydrous arc suites may have been overestimated based on analyses of porphyritic rock samples, and we should be careful of equating high-Al with calcalkalic. For example, studies of glass shards in arc-derived ash layers (recovered by deep-sea drilling), which represent the genuine liquid line of descent, uncompromised by crystal accumulation (Arculus et al., 1995), have demonstrated the following (Fig. 4) for the Mariana arc:

1. whereas the compositional spread of lavas erupted through the Tertiary–Quaternary from this arc system straddles the calcalkaline–tholeiitic boundary of Miyashiro (1974), the vast majority (excluding Eocene boninitic samples) of the glasses are tholeiitic in character;
   
2. most of the glass compositions span the range from low to medium K, with a few high-K glasses. The majority of the medium-K glasses are also tholeiitic, demonstrating the non-equivalence of ‘medium-K = calcalkaline’;
   
3. in the case of the Mariana arc (and in fact, also the Izu–Bonin and Kurile–Kamchatka systems), the overwhelming majority of glasses in the basalt to rhyolite compositional range have <17 wt % Al₂O₃. In contrast, wt % Al₂O₃ ranges up to 20% (or more) in the lavas, and many of these appear to be enriched in plagioclase phenocrysts (see also Crawford et al., 1987).
   

View larger version (52K): [in this window] [in a new window]   Fig. 4. Plots of wt % K2O and FeO*/MgO vs wt % SiO2 for individual glass shard compositions (determined by electron microprobe analysis; Arculus et al., 1995) recovered in the Mariana forearc (Deep Sea Drilling Project Sites 458 and 459), sourced from Tertiary–Quaternary arc eruptions. Discriminant boundaries in (a) and (b) are from Gill (1981) and in (c) and (d) from Miyashiro (1974). It should be noted that for both Sites, there is no coupled relationship between the K2O contents and the FeO*/MgO as a function of wt % SiO2, wherein med-K samples by the Gill (1981) criterion are automatically calcalkalic by the Miyashiro (1974) discriminant.

 

	SUMMARY

TOP ABSTRACT INTRODUCTION THE PROBLEM A PROPOSAL SOME EXAMPLES AND COMMENTS SUMMARY REFERENCES

 
The present application of the terms calcalkaline and calcalkalic is plagued with inconsistency, with the terms having different meanings for different users. Unfortunately, the terms are used for a variety of geochemical characteristics that are not necessarily correlated, and typically have no relationship with ‘calc’ or ‘alkaline’ character. Given the association in many geologists' minds of calcalkaline rock suites with active or ancient subduction zones, we are also liable to erroneously assert the former existence of tectonic environments on the basis of mistaken rock suite labelling and classifications. Recognizing the importance of the degree of FeO*/MgO enrichment with SiO₂ concentration in evolving subalkaline magma series, probably reflecting the critical effects of f_O2 variations and H₂O contents, I suggest we use labels that explicitly acknowledge the variability of FeO*/MgO (in addition to the spread of K₂O contents) as a function of SiO₂ content in our defining terminology. Furthermore, we should reserve the terms calcalkaline and calcalkalic solely for those suites that conform to Peacock's (1931) discriminants.

	ACKNOWLEDGEMENTS

 
Discussions with numerous colleagues at the State of the Arc (2000) Meeting in New Zealand, especially Jon Davidson, Mike Dungan, John Gamble, Chris Nye and Richard Price, and subsequently with Ross Taylor, were informative and influential. Very helpful journal reviews by Richard Price and an anonymous reviewer were constructive. David Fastovsky steered me in the right direction, and Marge Wilson's positive response is appreciated. This research has been supported by the Australian Research Council.

	REFERENCES

TOP ABSTRACT INTRODUCTION THE PROBLEM A PROPOSAL SOME EXAMPLES AND COMMENTS SUMMARY REFERENCES

 
Arculus, R. J., Gust, D. A. & Kushiro, I. (1991). Fuji and Hakone. Research and Exploration 7, 276–309.

Arculus, R. J., Gill, J. B., Cambray, H., Chen, W. & Stern, R. J. (1995). Geochemical evolution of arc systems in the western Pacific: the ash and turbidite record recovered by drilling. In: Taylor, B. & Natland, J. (eds) Active Margins and Marginal Basins of the Western Pacific. Geophysical Monograph, American Geophysical Union 88, 45–65.

Carmichael, I. S. E. (1964). The petrology of Thingmuli, a Tertiary volcano in eastern Iceland. Journal of Petrology 5, 435–460.[Abstract/Free Full Text]

Chayes, F. (1965). Statistical petrography. Carnegie Institution of Washington Yearbook 64, 153–165.

Crawford, A. J., Falloon, T. J. & Eggins, S. M. (1987). The origin of island arc high-alumina basalts. Contributions to Mineralogy and Petrology 97, 417–430.[CrossRef][Web of Science]

Fenner, C. N. (1929). The crystallization of basalts. American Journal of Science 18, 225–253.

Gill, J. B. (1981). Orogenic Andesites and Plate Tectonics. Berlin: Springer.

Grove, T. L. & Kinzler, R. J. (1986). Petrogenesis of andesites. Annual Review of Earth and Planetary Sciences 14, 417–454.[CrossRef][Web of Science]

Grove, T. L., Gerlach, D. C. & Sando, T. W. (1982). Origin of calc-alkaline series lava at Medicine Lake volcano by fractionation, assimilation and mixing. Contributions to Mineralogy and Petrology 80, 160–182.[Web of Science]

Gust, D. A., Arculus, R. J. & Kersting, A. B. (1997). Aspects of magma sources and processes in the Honshu arc. Canadian Mineralogist 35, 347–365.[Web of Science]

Hancock, P. L., Skinner, B. J. & Dineley, D. L. (2000). The Oxford Companion to the Earth. Oxford: Oxford University Press.

Harker, A. (1909). The Natural History of Igneous Rocks. London: Methuen.

Hatch, F. H., Wells, A. K. & Wells, M. K. (1961). Petrology of the Igneous Rocks. London: Murby.

Holmes, A. (1918). The basaltic rocks of the Arctic region. Mineralogical Magazine 18, 180–223.

Iddings, J. P. (1892). The origin of igneous rocks. Bulletin of the Philosophical Society of Washington 12, 89–214.

Irvine, T. N. & Baragar, W. R. (1971). A guide to the chemical classification of the common igneous rocks. Canadian Journal of Earth Sciences 8, 523–548.[Web of Science]

Kersting, A. B. & Arculus, R. J. (1994). Klyuchevskoy volcano, Kamchatka, Russia: the role of high-flux, recharged, tapped and fractionated magma chamber(s) in the genesis of high-Al₂O₃ from high-MgO basalt. Journal of Petrology 35, 1–41.[Abstract/Free Full Text]

Kuno, H. (1950). Petrology of Hakone Volcano and adjacent areas. Geological Society of America Bulletin 61, 957–1020.[Abstract/Free Full Text]

Kuno, H. (1968). Differentiation of basalt magmas. In: Hess, H. H. & Poldervaart, A. A. (eds) Basalts: The Poldervaart Treatise on Rocks of Basaltic Composition, 2. New York: Interscience, pp. 623–688.

Le Bas, M. J., Le Maitre, R. W., Streckeisen, A. & Zanettin, B. (1986). A chemical classification of volcanic rocks based on the total alkali–silica diagram. Journal of Petrology 27, 745–750.[Abstract/Free Full Text]

Miyashiro, A. (1974). Volcanic rock series in island arcs and active continental margins. American Journal of Science 274, 321–355.[Abstract]

O'Neill, H. St.C. & Mavrogenes, J. A. (2002). The sulfide capacity and the sulfur content at sulfide saturation of silicate melts at 1400°C and 1 bar. Journal of Petrology 43, 1049–1088.[Abstract/Free Full Text]

Osborn, E. F. (1959). Role of oxygen partial pressure in the crystallization and differentiation of basaltic magma. American Journal of Science 257, 609–647.[Abstract/Free Full Text]

Osborn, E. F. (1979). The reaction principle. In: Yoder, H. S. (ed.) The Evolution of the Igneous Rocks: Fiftieth Anniversary Perspectives. Princeton, NJ: Princeton University Press, pp. 133–169.

Peacock, M. A. (1931). Classification of igneous rock series. Journal of Geology 39, 54–67.

Rollinson, H. R. (1993). Using Geochemical Data: Evaluation, Presentation, Interpretation. Harlow: Longman.

Streckeisen, A. (1976). To each plutonic rock its proper name. Earth-Science Reviews 4, 1–33.

Wager, L. R. & Deer, W. A. (1939). Geological investigations in East Greenland: Part III. The petrology of the Skaergaard Intrusion, Kangerdluqssuaq, East Greenland. Meddelelser om Gronland 150, 1–352.

Wilkinson, J. F. G. (1968). The petrography of basaltic rocks: In: Hess, H. H. & Poldervaart, A. A. (eds) Basalts: The Poldervaart Treatise on Rocks of Basaltic Composition, 2. New York: Interscience, pp. 163–214.

Yoder, H. S. & Tilley, C. E. (1962). Origin of basalt magmas: an experimental study of natural and synthetic rock systems. Journal of Petrology 3, 342–532.[Abstract/Free Full Text]

Young, D. A. (1998). N. L. Bowen and Crystallization–Differentiation: the Evolution of a Theory. Mineralogical Society of America, Monograph Series, Publication 4.

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