Magma-reservoir crystallization processes: small-scale dikes in cumulate grabbros, Mauna Kea Volcano, Hawaii

Author:

Hoover, S.R., Fodor, R.V.

Title:

Magma-reservoir crystallization processes: small-scale dikes in cumulate grabbros, Mauna Kea Volcano, Hawaii

Periodical:

Bulletin of Volcanology

Year:

1997

Volume:

59

Pages:

186-197

Subject:

Gabbro Dikes Xenoliths Mauna Kea Cumulates Magma reservoir

Summary:

An examination of more than 100 gabbroic xenoliths from Mauna Kea, a volcano on the island of Hawaii, showed that some of these xenoliths are composites of host gabbros that were cross cut by small-scale gabbroic dikes. Since the Mauna Kea gabbroic xenoliths have stored-up origins, a detailed study of these dike/host composites can provide information about magma-reservoir processes that appear to involve movement of magmatic liquid through the accumulation of olivine, pyroxene, and plagioclase crystals. As a result, the main objective of this study was to establish whether small-scale dikes that form in crystallizing reservoirs represent magmatic liquids that are unrelated to the cumulate gabbros or to determine if they are related to the cumulate via parentages in the same magmas that crystallized the gabbroic hosts for the dikes. Whichever the case may be, geochemical and mineralogic examinations of these dike/host composite xenoliths revealed information about magma reservoir liquid-solid interactions that would otherwise remain unobserved. As a result, whole-rock and mineral compositional data and interpretations for four such composite xenoliths are presented here.

Label:

Geology

URL:

http://cletus.uhh.hawaii.edu:2074/10.1007/s004450050185

Collection:

Periodicals