Answer: stratifications

AnswerCrossword Clue
stratificationsSTRATIFICATION, (Geol.) the accumulation of material in layers or beds
stratificationsformation of or occurrence in layers of rock or similar strata
stratificationshierarchical or vertical division of society according to rank, caste, or class
stratificationsstratified state or appearance
stratificationsact or an instance of placing in strata, or layers