World Data Service for Geophysics

Index to Marine and Lacustrine Geological Samples (IMLGS)
an international partnership

doi:10.7289/V5H41PB8


Repository: SOEST [Contact the Curator]
Ship: Melville
Cruise: BMRG06MV
Sample: BMRG06MV STA86 RD76
Device: dredge, rock
Latitude: -32.76283
Longitude: 77.8865
Water Depth(m): 2090 to 2265
Date: 19960403
PI: Kevin Johnson
Storage: room temperature, dry
Province: rise or ridge, aseismic ocean

Southeast Indian Ridge; Sampling locale: seamount ~18 km north of segment H ridge axis.
1 :   
Weathering/Metamorphism: weathering - light
Comments: Sample Type: Pahoehoe lavas_Aphyric basalt. Mineralogy: aphyric (rare olivine and plagioclase microphenos?). Weathering: Light. Glass condition: >50% fresh glass. 2 buckets.Sampled for probe. Subsampled by DG. All other glass to KJ. Several large pieces with well - preserved flow features in glass, and numerous smaller ones, are included as unnumbered samples, wrapped in bubble wrap. DG has two hand size unnumbered pieces.Fresh, glassy pahoehoe lava pieces with glassy margins ~ 1 cm thick and outer Mn oxide coating. Type 1 of this dredge.
2 :   
Weathering/Metamorphism: weathering - light
Comments: Sample Type: Sheet flow basalt_Aphyric basalt. Mineralogy: aphyric, with rare olivine (and plagioclase ? ). Weathering: Light. Glass condition: >50% fresh glass. 2 buckets.Sampled for probe. Subsampled by DG. All other glass to KJ. Several smaller pieces are included as unnumbered samples, wrapped in bubble wrap. DG has one hand size unnumbered piece.Fresh, sheet flow basalt with outer surface of Mn oxide coated glass ~0.5 cm thick, and underside with non-glassy drainback features. Type 2 of this dredge.
3 :   
Comments: Sample Type: Aphyric basalt. Mineralogy: minor plagioclase and olivine. Weathering: Light to moderate. Glass condition: Some fresh glass. 2 buckets.Sampled for probe. Subsampled by DG. All other glass to KJ. 2 small pieces are included as unnumbered samples. Sampled by KN.Basalt fragments with thin glass margins and greyish interiors, apparently older than types 1 or 2. Type 3 of this dredge.
4 :   
Comments: Sample Type: Aphyric basalt. Mineralogy: olivine and plagioclase. Weathering: Moderate to heavy. Glass condition: some altered glass. 2 buckets.Sampled for probe. All other glass to KJ. only one sample of this type in the dredge. KN sampled 76-6.Basalt fragments with very thin glass margins and greyish interiors with yellow staining and more noticeable amounts of plag and oliv thant ypes 1-3. Type 4 of this dredge.
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