Assertion: glacier's period | /r/HasProperty | marked by warm and cold episodes
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text: The current geological period, the Quaternary, which began about 2.6 million years ago and extends into the present, is marked by warm and cold episodes, cold phases called glacials (Quaternary ice age) lasting about 100,000 years, and which are then interrupted by the warmer interglacials which lasted about 10,000–15,000 years.