Chemical variability in the Lakeview Mountains pluton, southern California batholith: A comparison of the methods of correspondence analysis and extended Q-mode factor analysis
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Abstract
An extended method of Q-mode factor analysis that has been described previously offers a number of important advantages over conventional Q-mode factor analysis and correspondence analysis when applied to compositional data. Among these are the ability to compute the compositions, in the original units of the data, represented by the reference axes. The only special requirement of the data is that the values for each observation sum to a constant. Mathematically derived reference axes, such as the principal-components and varimax axes, commonly represent compositions that are partly negative. Even where no negative values are present, these compositions are comparatively difficult to interpret in petrologic terms and impossible or inappropriate to include in petrogenetic models. A model has been developed for the Lakeview Mountains pluton which employs vectors representing the compositions of melanocratic schlieren, leucocratic schlieren, and inclusions as the reference axes. When the effect of the inclusions is removed, the compositional zoning in the pluton is like that found in otherwise similar plutons in the Sierra Nevada batholith. The genetic implication of the model is that the inclusions were separated from the magma at least in its marginal parts. In the central part of the pluton, the inclusions were either separated to a lesser extent than in the marginal parts, or were reincorporated into the magma.
Study Area
| Publication type | Article |
|---|---|
| Publication Subtype | Journal Article |
| Title | Chemical variability in the Lakeview Mountains pluton, southern California batholith: A comparison of the methods of correspondence analysis and extended Q-mode factor analysis |
| Series title | Journal of Research of the U.S. Geological Survey |
| Volume | 5 |
| Issue | 1 |
| Year Published | 1977 |
| Language | English |
| Publisher | U. S. Geological Survey |
| Description | 14 p. |
| First page | 103 |
| Last page | 116 |
| Country | United States |
| State | California |
| Other Geospatial | Lakeview Mountains, Lakeview Mountains pluton, Southern California batholith |
| Google Analytic Metrics | Metrics page |