Lherzolitic shergottite ALH 77005 is one of the most primitive martian meteorites. To characterize the parental melt of this primitive meteorite, olivine and chromite-hosted melt inclusions have been experimentally rehomogenized. The rehomogenization was performed with hydrostatic pressures (800-1000 bars) of CO 2 + CO gas along with finely powdered graphite at temperatures of 1150-1185 °C. Equilibrium between the host and inclusion melt was determined based on the lack of zonation in the host surrounding the melt inclusion, equilibrium K D values of host and melt inclusions, and textures of the melt inclusion. Chromite-hosted melt inclusions, where chromite is poikilitically enclosed by olivine, contain ~7.5 wt% MgO. This composition most closely reflects the parental melt of ALH 77005. The melts trapped in Fo 75 olivine contain ~7.1 wt% MgO when brought to equilibrium with the host. This olivine-hosted melt inclusion composition has lower SiO 2 (~50 vs. 53.9 wt%) and higher Cr 2 O 3 (~1.2 vs. 0.2 wt%) and P 2 O 5 (~1.2 vs. 0.5 wt%) than previous estimates for ALH 77005. In addition, compared with the chromite-hosted inclusions, the olivine-hosted ones have higher Al 2 O 3 and lower CaO than can be explained through crystallization of phases known to be on the liquidus. This finding suggests that magma mixing occurred between chromite and olivine crystallization or olivine-hosted inclusions were contaminated by secondary minerals such as phosphate. Both olivineand chromite-hosted melt inclusions in ALH 77005 have slightly higher Al 2 O 3 than olivine inclusions in Chassigny but significantly higher Al 2 O 3 than nakhlites such as MIL 03346 and Nakhla at similar values of MgO.

Ash deposits are found interbedded within organic mudstones such as the Vaca Muerta, Niobrara and Eagle Ford shales. Alteration of ash deposits interbedded within mudstones and shales have presented challenges for completion and production including pinching of fractures and swelling upon contact with drilling and completion fluids. This paper will review the mineralogic and petrologic variations in altered ash beds found within the Eagle Ford and examine the impact these chemical and physical properties can have on completion. The paper will also present a methodology for detection of ash beds using high-resolution measurements. Understanding and detecting the mineralogic variation between the altered ash beds will enable better completion and minimize risk during production.

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