Magmatic differentiation in Hawaii

Author:

Daly, Reginald A.

Title:

Magmatic differentiation in Hawaii

Periodical:

Journal of Geology

Year:

1911

Volume:

19

Pages:

289-316

Subject:

Magma Geology Mauna Kea

Summary:

This is the earliest paper to treat the differentiation of Hawaiian magmas in a systematic way. Chemical analyses are given for the Uwekahuna laccolith, olivine from the 1852 Mauna Loa flow, andesite typical of the upper slopes of Mauna Kea, and a light-colored flow from the summit cinder cone of Mauna Kea. The chemical data was compiled by George Steiger, one of the early analysts to work on Hawaiian lava. R.A. Daly makes the following conclusions regarding magmatic differentiation: 1. The chemical composition of the average Hawaiian basalt is equal to that of the average basalt worldwide; 2. The sequence of rock types found on Mauna Kea, from bottom to top, is explained by gravitative differentiation in normal basaltic magma; 3. W.L. Green's 1887 view of the existence of worldwide molten basaltic substratum is correct; and 4. Xenoliths result from chrystallization in a viscous magma in which they cannot sink, which contrasts with current observation that xenoliths are brought to the surface from great depth by rapid transport in magmas of low viscosity.

Label:

Geology

URL:

http://www.jstor.org/stable/30060006

Collection:

Periodicals