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Imogolite and allophane formed in saprolite of basalt on Maui, Hawaii

Clays and Clay Minerals

By:
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https://doi.org/10.1346/CCMN.1972.0200605

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Abstract

Inorganic gel and allophane collected from basaltic saprolite on Maul, Hawaii, and studied by Patterson in I964 were reexamined. The main constituent of the gel is imogolite, and gibbsite and allophane are the minor constituents. Electron and X-ray diffraction patterns, DTA curve, and an infrared spectrum of the gel are characteristic of imogolite. The allophane is virtually noncrystalline to X-rays but contains a small amount of imogolite in relatively short threads. High-resolution electron micrographs indicate differences in structural organization between allophane and imogolite and suggest crystallization of imogolite from allophane.

The occurrence of imogolite as a weathering product has been reported in many localities from pyroclastic materials but not from massive rocks. Probably the exceptionally high rainfall, excellent subsurface permeability of the weathered material, and the low pH and high organic content of the leaching solution provide favorable conditions for formation of imogolite from basalt on Maul.

Additional publication details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Imogolite and allophane formed in saprolite of basalt on Maui, Hawaii
Series title:
Clays and Clay Minerals
DOI:
10.1346/CCMN.1972.0200605
Volume:
20
Issue:
6
Year Published:
1972
Language:
English
Publisher:
The Clay Minerals Society
Description:
6 p.
First page:
375
Last page:
380
Country:
United States
State:
Hawaii
Other Geospatial:
Maui