Abstract
LAP 02205 (LAP) is fifth crystalline mare basalt. We investigated its crystallization history using MELTS calculation and performing crystallization experiments. The results from both MELTS and crystallization experiments showed that the liquidus phase from the LAP bulk composition is olivine whose composition is more Fe-rich than the core composition of LAP olivine suggesting the xenocryst origin of the Mg-rich core of olivine. However, the core compositions and zoning sequences are similar among LAP and synthetic pyroxenes. Therefore, the LAP bulk composition is similar to its parent melt composition because olivine is rare in LAP (2~6%) The pyroxene and olivine mineralogy of experimental charges suggest 1-5 oC/hr cooling rate during the crystallization of the LAP magma.
