San Carlos Clinopyroxene Rich Peridotite Group Ii Is It Possible To Group ii inclusions are dominated by clinopyroxene rich peridotites containing al and ti rich augite and commonly abundant, al rich spinel. compared to group i inclusions, they are more fe rich (mg mg Σfe= 0.62 – 0.78) and more hetereogeneous in composition and modal proportions. similar groups occur at many ultramafic inclusion localities. San carlos is a small (< 50 km 2), miocene to quaternary volcanic field located in the san carlos apache indian reservation. the samples studied are from the peridot mesa, a vent flow complex comprising a diatreme (peridotite hill) and alkaline rich basanite flow ( hadnott et al., 2017 ; wohletz, 1978 ) dated at 0.58 ± 0.21 ma by k ar ages ( bernatowicz, 1981 ).
Peridotite Mantle Xenolith In Vesicular Phonotephrite Peridot Mesa The available data indicate possible stratification of the cratonic lithosphere in some locations, with olivine rich peridotite at shallow depth 38 and normal and or orthopyroxene rich peridotite. Average mineral modes calculated from the three group 1 samples show 66% olivine, 21% orthopyroxene, and 13% clinopyroxene (mineral percentage for the separate samples (by counting the pixels of. As discussed above, the most prominent differences between types ii and iii clinopyroxene domains are two fold: (1) type iii clinopyroxene domains exhibit much less degree of mree enrichment over hree [i.e. lower (dy yb) n] than type ii clinopyroxene domains (fig. 6 a); (2) type iii clinopyroxene domains exhibit much stronger negative eu anomalies than type ii clinopyroxene domains (fig. 6 a. This finding is consistent with the absence of clinopyroxene porphyroclast, which constrains stage 1 temperatures to above the clinopyroxene out curve in the hydrous peridotite system (>1120 °c.
Flickriver Photoset Peridot Mesa San Carlos Volcanic Field As discussed above, the most prominent differences between types ii and iii clinopyroxene domains are two fold: (1) type iii clinopyroxene domains exhibit much less degree of mree enrichment over hree [i.e. lower (dy yb) n] than type ii clinopyroxene domains (fig. 6 a); (2) type iii clinopyroxene domains exhibit much stronger negative eu anomalies than type ii clinopyroxene domains (fig. 6 a. This finding is consistent with the absence of clinopyroxene porphyroclast, which constrains stage 1 temperatures to above the clinopyroxene out curve in the hydrous peridotite system (>1120 °c. 1989; menzies, 2003). the pyroxene rich lithologies include orthopyroxenites, websterites, and clinopyroxenites with varying olivine contents. the orthopyroxene rich group i rocks are interpreted as either residual tectonic layer in peri dotites, or as cumulates from the extracted basaltic liquid. clinopyroxene rich rocks may occur as layers or. A comparison between the modeled clinopyroxene compositions and clinopyroxene clusters 1–3, shows that the majority of clinopyroxene compositions can be explained by spinel field melting with retained melt fractions varying between α = 0.001 and α = 0.02 (figure 6a) (brunelli et al., 2006). however, some cluster 3 clinopyroxenes have particularly high pc1 at moderately high pc2, which may.
Pressure Temperature Phase Diagram Of The San Carlos Peridotite Ol 1989; menzies, 2003). the pyroxene rich lithologies include orthopyroxenites, websterites, and clinopyroxenites with varying olivine contents. the orthopyroxene rich group i rocks are interpreted as either residual tectonic layer in peri dotites, or as cumulates from the extracted basaltic liquid. clinopyroxene rich rocks may occur as layers or. A comparison between the modeled clinopyroxene compositions and clinopyroxene clusters 1–3, shows that the majority of clinopyroxene compositions can be explained by spinel field melting with retained melt fractions varying between α = 0.001 and α = 0.02 (figure 6a) (brunelli et al., 2006). however, some cluster 3 clinopyroxenes have particularly high pc1 at moderately high pc2, which may.
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