aa

A form of lava flow associated with Hawaiian-type volcanoes, consisting of basaltic rock, usually dark-colored with a jagged and loose, clinkery surface. Compare pahoehoe.

We...saw ‘pahoihoi’ or solid lava forming, and also ‘aa’ or clinkers.

Cooling and solidification frequently takes a different course [...] in lava flows, producing the clinker-like ‘aa’ lava.

Both pahoehoe and aa lava flows are common on the upper slopes of Mauna Loa with a preponderance of aa flows found at the lower elevations.

Variante de acetic acidInitialism of acetic acid.

Variante de acting ageInitialism of acting age.

Variante de alveolar-arterialInitialism of alveolar-arterial.

Variante de aminoacetoneInitialism of aminoacetone.

Variante de amino acidInitialism of amino acid.

Variante de approximate absoluteInitialism of approximate absolute.

Variante de arachidonic acidInitialism of arachidonic acid.

Variante de armature acceleratorInitialism of armature accelerator.

Variante de ascending aortaInitialism of ascending aorta.

Variante de atomic absorptionInitialism of atomic absorption.

Variante de author's alterationInitialism of author's alteration.

Variante de average audienceInitialism of average audience.

Variante de arctic-alpineInitialism of arctic-alpine.

Variante de always afloatInitialism of always afloat.

Variante de adjectivesAbbreviation of adjectives.

Variante de arteriesAbbreviation of arteries.

Variante de anaAbbreviation of ana (“of each, equal parts”).

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