Petrology of basalt from the East Pacific Rise near 21 degrees North latitude

James G. Moore; William R. Normark; Gordon R. Hess; Charles E. Meyer

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Petrology of basalt from the East Pacific Rise near 21 degrees North latitude

James G. Moore·William R. Normark·Gordon R. Hess·Charles E. Meyer

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Abstract

Four dredge hauls of fresh tholeiitic basalt lava were recovered from a 3.3-kilometer-wide zone at the axis of the East Pacific Rise. Petrologic and major-element chemical studies indicate that the basalt ranges from moderately fractionated varieties to one sample enriched in iron and titanium. The four samples show no symmetrical compositional zonation across the ridge axis, but the two least fractionated and youngest samples occur on the east side of the ridge axis.

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Journal of Research of the U.S. Geological Survey Article

Source-reported bounding extent: 19.497664168139053° to 23.180763583129444° latitude; -110.32470703125° to -107.5341796875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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James G. Moore, William R. Normark, Gordon R. Hess, Charles E. Meyer. 1977. Petrology of basalt from the East Pacific Rise near 21 degrees North latitude. https://pubs.usgs.gov/publication/70233491

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