Source characteristics derived from very incompatible trace elements in Mauna Loa and Mauna Kea basalts, Hawaii Scientific Drilling Project

Author:

Hofmann, A.W., Jochum, K.P.

Title:

Source characteristics derived from very incompatible trace elements in Mauna Loa and Mauna Kea basalts, Hawaii Scientific Drilling Project

Periodical:

Journal of Geophysical Research

Year:

1996

Volume:

101

Pages:

11,831- 11,839

Subject:

Hawaii Scientific Drilling Project Trace elements Basalt Mauna Kea Basalt Mauna Loa

Summary:

We report trace element analyses by Spark Source Mass Spectrometry of selected Hawaii Scientific Drilling Project samples for Mauna Loa and Mauna Kea basalts and picrites. These results are similar to those previously found for both Mauna Loa and Kilauea lavas. Six Hawaiian volcanoes for which extensive sets of high-quality Ba-Th-U-La data exist (Mauna Kea, Mauna Loa, Kilauea, Loihi, Haleakala, and Koolau) are all distinguished by a characteristic depletion of Th and U relative to Ba and La. This distinctive, nonprimitive "fingerprint" is found both in tholeiites and alkali basalts, and it is clearly a property of the present-day Hawaiian source rather than the product of fractionation during (or after) partial melting. Thus, the Hawaiian plume must contain strongly fractionated mantle material. We speculate that the Hawaiian source contains significant amounts of recycled oceanic gabbros.

Label:

Geology

Collection:

Periodicals