High alumina (HA) and very high potassium (VHK) basalt clasts from Apollo 14 breccias. I - Mineralogy and Petrology - Evidence of crystallization from evolving magmasThe mineralogy and petrography of very high potassium (VHK) and high alumina (HA) basalts from the Apollo 14 site provide an insight into their magmatic evolution. Generally, their parageneses are similar, with olivine and chromite the early liquidus phases, followed by plagioclase and pyroxene, which crystallized together. Although late-stage ilmenite and FeNi metal occur in both VHK and HA samples, the VHKs also crystallize K-feldspar and Fa-rich olivine. Zoning of constituent minerals is similar for both basalt types, demonstrating that the parental magmas for both HA and VHK basalts became enriched in K, Na, Ca, Fe, and Ti and depleted in Mg and Al as crystallization proceeded. Enrichment of K in the VHK basalts is above that expected from normal fractional crystallization.
Document ID
19890049126
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Neal, C. R. (Tennessee Univ. Knoxville, TN, United States)
Taylor, L. A. (Tennessee Univ. Knoxville, TN, United States)
Patchen, A. D. (Tennessee, University Knoxville, United States)