CGRG Bibliography of Canadian Geomorphology
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Author : Brown, A.S.
Date : 1969
Title : Aiyansh lava flow, British Columbia
Publication : Canadian Journal of Earth Sciences
Issue : 6(6):
Page(s) : 1460-1468
Abstract
The Aiyansh flow, about 220 years old, came from a vent in a narrow tributary valley of the Tseax River, flowed 14 miles to the Nass valley, and there spread out in a lava plain six miles long, forcing the river to the northern margin of the valley. The flow has an area of about 15 sq mi and a volume of about 0.1 cubic miles. It is a single cooling unit, the surface composed of pahoehoe, slab, and block lava in a pattern related to slope. Piping and collapse were important near the margins. The flow is entirely a fresh black alkali basalt varying only slightly in crystallinity and texture. Holocrystalline specimens from the interior consist of about 50 percent plagioclase, 10 percent olivine, 30 percent pyroxene, and 10 percent opaques. A new chemical analysis confirms that it is a high-iron, low-magnesium, alkali basalt.
Bibliography of Canadian Geomorphology