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 di acetic acidInitialism of acetic acid.

Variante di acting ageInitialism of acting age.

Variante di alveolar-arterialInitialism of alveolar-arterial.

Variante di aminoacetoneInitialism of aminoacetone.

Variante di amino acidInitialism of amino acid.

Variante di approximate absoluteInitialism of approximate absolute.

Variante di arachidonic acidInitialism of arachidonic acid.

Variante di armature acceleratorInitialism of armature accelerator.

Variante di ascending aortaInitialism of ascending aorta.

Variante di atomic absorptionInitialism of atomic absorption.

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

Variante di average audienceInitialism of average audience.

Variante di arctic-alpineInitialism of arctic-alpine.

Variante di always afloatInitialism of always afloat.

Variante di adjectivesAbbreviation of adjectives.

Variante di arteriesAbbreviation of arteries.

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

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