glaciations

Noun

glaciation (countable and uncountable, plural glaciations)

1. The process of covering with a glacier, or the state of being glaciated; the production of glacial phenomena; an ice age
   • That the habitability of our planet was severely endangered by the significant rise in oxygen levels and reduction in methane due to oxygen-producing bacteria combined with the low luminosity of the Sun in the Proterozoic era (2500– 542 million years ago) is suggested by geological evidence for...2005, Peter Ulmschneider, Intelligent Life in the Universe: Principles and Requirements Behind Its Emergence
2. A particular instance of glacier formation.
   • Deposits of the Caribou Hills glaciation only locally retain a distinct hummocky morainal form, with filled kettle depressions and subdued knobs. Along the mountain fronts the marginal deposits of this glaciation reach an average altitude of slightly more than 3,000 feet.1953, Geological Survey Circular, The Survey, page 4
3. The act of freezing.
   • For cave glaciation to occur it is necessary that the air temperature outside the caves be negative either for all or part of a year; such conditions exist in many regions of the world.2017, Aurel Persoiu, Ice Caves