Figure F2. Stratigraphic variations of modal composition and grain size of minerals in Units II and III (Cores 345-U1415P-3R through 23R; ghost cores not included) based on visual core description. Grain size: black lines = mode, blue diamonds = maximum. Some of the plagioclase (Plg) for which a coarse grain size (~10 mm) was macroscopically estimated in rock of Unit II actually represent aggregates of much finer grained plagioclase crystals (average size = ~0.3 mm). In Unit II, very coarse grained clinopyroxene (Cpx) grains were observed. Microscopic examination of these clinopyroxenes confirmed that they are large optically continuous poikilitic grains. In Unit III, clinopyroxene is a minor interstitial component and very small grain sizes were visually estimated. However, under microscopic examination, many of the interstitial grains are actually parts of centimeter-sized optically continuous clinopyroxenes. Ol = olivine, Opx = orthopyroxene, OXs = oxides.
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