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Full-Text Articles in Earth Sciences
Petrology And Geochemistry Of Late-Stage Intrusions Of The A-Type, Mid-Proterozoic Pikes Peak Batholith (Central Colorado, Usa): Implications For Petrogenetic Models, Diane R. Smith, J. Noblett, R. A. Wobus, D. Unruh, J Douglass, R. Beane, C. Davis, S. Goldman, G. Kay, B. Gustavson, B. Saltoun, J. Stewart
Petrology And Geochemistry Of Late-Stage Intrusions Of The A-Type, Mid-Proterozoic Pikes Peak Batholith (Central Colorado, Usa): Implications For Petrogenetic Models, Diane R. Smith, J. Noblett, R. A. Wobus, D. Unruh, J Douglass, R. Beane, C. Davis, S. Goldman, G. Kay, B. Gustavson, B. Saltoun, J. Stewart
Geosciences Faculty Research
The ~1.08 Ga anorogenic, A-type Pikes Peak batholith (Front Range, central Colorado) is dominated by coarse-grained, biotite ± amphibole syenogranites and minor monzogranites, collectively referred to as Pikes Peak granite (PPG). The batholith is also host to numerous small, late-stage plutons that have been subdivided into two groups (e.g. Wobus, 1976. Studies in Colorado Field Geology, Colorado School of Mines Professional Contributions, Colorado): (1) a sodic series (SiO2 = ~44–78 wt%; K/Na = 0.32–1.36) composed of gabbro, diabase, syenite/quartz syenite and fayalite and sodic amphibole granite; and (2) a potassic series (SiO2 = ~70–77 wt%; K/Na = 0.95–2.05), …
A Review Of The Pikes Peak Batholith, Front Range, Central Colorado: A "Type Example" Of A-Type Granitic Magmatism, Diane R. Smith, J. Noblett, R. A. Wobus, D. Unruh, K. R. Chamberlain
A Review Of The Pikes Peak Batholith, Front Range, Central Colorado: A "Type Example" Of A-Type Granitic Magmatism, Diane R. Smith, J. Noblett, R. A. Wobus, D. Unruh, K. R. Chamberlain
Geosciences Faculty Research
The N 1.08-Ga Pikes Peak composite batholith of central Colorado is a type example of an Atype granitic system. From the 1970s through the 1990s, details of the field relations, mineralogy, major and trace element compositions, and isotopic geochemistry of Pikes Peak rocks were documented, and they reveal the existence of two chemical groups, a potassic and a sodic series. The potassic series (~64-78 wt % SiO2) includes the Pikes Peak Granite, which is mostly coarse-grained biotite f hornblende syenogranite and minor monzogranite that dominates the batholith. The potassic series also includes fine- to medium-grained biotite granite found …