5-1. Nuuanu far side (D11)

Petrography
Dredge 11:D11-1 and D11-2 samples are X=30cm, Y=18, Z=11cm in size and 13kg in weight and X=24cm, Y=17, Z=7cm, 3kg, respectively. Thicknesses of Mn-coating of the two samples are in the range 1 mm to 2.5 mm. Color of both samples are dark brown. Grain size of fragments in rocks vary from less than 1 mm up to 64mm. Fragments in the volcaniclastic rocks are basalts which are brown or black in color. Some of the fragments appear to be red by the naked eye, indicating that these fragments were oxidized in subaerial condition. Olivine phenocrysts are common in the fragments. Chromite, melt inclusions and fluid inclusions are included in some of them. Most of the groundmass has hyalophitic, intersertal textures, however some fragments have intergranular texture. Two types of fragments, sideromelane and tachylite, are recognized in groundmass. The sideromelane is brown in color and the tachylite appears black. These textures and type of glasses may imply that most of the volcanic fragments are derived from different parts of quenched lavas that quenched quickly by sea water. Both rocks are altered. Many glass fragments are altered and form palagonite, and some palagonite has altered to form zeolite that appears crystalline in texture. Some olivine phynocrysts have alteration texture.

5-2. Kohala landslides (D12 and D13)

Petrography
Dredge 13: Seven samples were dredged (sample number D13-1 to D13-7) in D13 site. Samples D13-1 to D13-3 are relatively larger (>5cm) than the others (<2cm). These rocks are black and lack Mn coating. Rocks have porphyritic and aphiric texture. All samples are very fresh and may be pillow basalt.

D13-1 clearly has pillow rim texture. The sample contains about 10% euhedral and subhedral olivine phenocrysts, with size normally less than 1 mm. Some chromite, melt inclusions and fluid inclusions are contained in olivine phenocrysts. The texture of the groundmass changes gradually from pillow basalt rim to interior. For example, in the pillow rim, there are microlites of plagioclase and hyaloplitic texture. The texture however, becomes intersertal or intergranular in the pillow interior. Also the color of glass changes from yellow-brown (sideromelane) in pillow rim to black (tachylite) in pillow interior. Sample D13-2 has an aphyric texture. Abundance of olivine phenocryst is less than 1%. Groundmass is composed of plagioclase, clinopyroxene and glasses (black, tachylite) and has intersertal or intergranular textures, indicating that this rock may be a part of pillow interior. Approximately 10% vesicles with diameter of about 0.8mm are present. About 5% of olivine phenocryst (nearly 0.2mm) is present in sample D13-3. Groundmass of this rock is composed of plagioclase, clinopyroxene and some glass (black, tachylite), having intersertal texture. Vesicle content is about 5%.

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