Petrologic history of the moon inferred from petrography, mineralogy, and petrogenesis of Apollo 11 rocks

摘要: The mineralogy and petrology of the Apollo 11 rocks are consistent with impact melting of ilmenite pyroxene crystals plus liquid derived from fractional crystallization basaltic magama. The complementary plagioclase accumulate should exist in highlands. ferrobasaltic magma is derived a differentiated hot moon modified chondritic composition. one-sided distribution of large irregular seas is explained by tidal attraction last fraction to the near side release meteorite impact. The vesicular ferrobasalt lavas contain ilmenite, clinopyroxene have textures similar some terrestrial basalts. Delayed appearance indicates an unusual source of the magma. iron-enrichment coarser microgabbros extreme at end crystallization resulting new iron metasilicate, pyroxferroite. The oxygen fugacity 1050°C these indicated composition opaque oxides and troilite-iron intergrowths 10^(-14)-10^(-16) compared 10^(- 11) for basalts about 10^(16) for ordinary chondrites. Absence hydrous minerals loss volatiles stage in the moon's history. The breccias soil same shock. Plagioclase vitrophyres are probably melted cumulates may derive Lithification breccia results principally welding debris discharged gas cloud created impact. Small glass spheres surface features fiery rain boiling silicate rounded by tension later impacted high-velocity micrometeorites. Melting experiments synthetic material mean rock revealed low liquidus temperature, delayed narrow crystal-liquid interval. These support concept advanced under reducing conditions leading high enrichment. Flotation sin king pyroxene should occur basalt. We propose that blasted away plagioclase-rich crust, melting mixture of fractionated basalt crystals. formed Sea of Tranquillity yielded near-surface lava flows represented ferrobasalts microgabbros. This could yield only after extra had crystallized. We original was molten moon yielding metallic core surrounded pressure-stable Mg-rich o li vine pyroxene. fractionated became Fe-rich resulting inverse density stratification. Primitive ultra basic crust highlands, along dominant plagio clase- rich cumulates. temperature-time relations model discussed qualitatively. Key factors early removal radioactive center possible enhancement of radiative heat transfer volatile-free silicates. be more refractory and rigid because low volatile content.