Petrology of Baby Bare and Mama Bare lavas

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doi: 10.1029/97GL53564
Author(s): Karsten, J. L.; Becker, N.; Mottl, M. J.; Wheat, C. G.
Author Affiliation(s): Primary:
University of Hawaii at Manoa, Honolulu, HI, United States
Other:
University of Alaska, United States
Volume Title: Geophysical Research Letters
Source: Geophysical Research Letters, 25(1), p.117-120. Publisher: American Geophysical Union, Washington, DC, United States. ISSN: 0094-8276 CODEN: GPRLAJ
Note: In English. 14 refs.; illus., incl. 1 table, sketch map
Summary: The Three Bares are small volcanoes that host the only-known hydrothermal vents active in oceanic crust older than 2 Ma. Major element data for Baby and Mama Bare lavas indicate formation by low extents of partial melting of a depleted mantle source, with limited cooling and crystallization prior to eruption. These lavas are compositionally unlike all lavas produced at the adjacent spreading center, but resemble a subset of lavas from small seamounts nearby. We conclude that the Three Bares represent off-axis volcanism rather than normal crustal accretion. Such off-axis volcanism increases basement roughness locally, and thus plays an important role in hydrothermal circulation in sedimented ridge flank settings. Copyright 1998 by the American Geophysical Union.
Year of Publication: 1998
Research Program: ODP Ocean Drilling Program
Key Words: 05 Petrology, Igneous and Metamorphic; Baby Bare; Chemical composition; East Pacific; Endeavour Ridge; Geochemistry; Heat flow; Hot spots; Hydrothermal vents; Juan de Fuca Ridge; Lava; Leg 168; Major elements; Mama Bare; North Pacific; Northeast Pacific; Ocean Drilling Program; Ocean floors; Pacific Ocean; Seamounts; Volcanoes
Coordinates: N480000 N490000 W1280000 W1300000
Record ID: 2000010595
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute.