Petrography and petrology of the Hawaii Scientific Drilling Project lavas: inferences from olivine phenocryst abundances and compositions

Author:

Baker, Michael B., Alves, Sophie, Stolper, Edward M.

Title:

Petrography and petrology of the Hawaii Scientific Drilling Project lavas: inferences from olivine phenocryst abundances and compositions

Periodical:

Journal of Geophysical Research

Year:

1996

Volume:

101

Pages:

11,715-11,727

Subject:

Hawaii Scientific Drilling Project Lava analysis Basalt Olivine

Summary:

The first phase of the Hawaii Scientific Drilling Project, (HSDP), core-drilled to a depth of 1,056 meters at a site just east of downtown Hilo. The upper (approximately) 280 meters of the core contained 27 flows from Mauna Loa and sequences of calcareous and volcaniclastic sediments. The lower (approximately) 776 meters of the core comprised of 184 identified flows from Mauna Kea. The boundary between these two Hawaiian volcano lava flows was well-defined based on the major- and trace-element and isotopic compositions of the lavas and the lava recovered by the HSDP from Mauna Loa and Mauna Kea included aphyric to highly olivine-phyric basalts. Ninety flows that were sampled as a reference suite for major- and trace-element and isotopic analysis. This paper summarizes the microscopic petrography of most of the these flows and focused on the compositions of olivines and their spinel inclusions from a subset of the flows. It was determined that the compositions of olivines and spinels in six centimeter-sized dunite xenoliths were from five tholeiite flows that occurred on Mauna Kea.

Label:

Geology

Collection:

Periodicals