Peat that forms in areas of high rainfall that is not dependent on groundwater but receives all its moisture from the atmosphere. It can form on higher ground like plateaus. In periods of climatic change, blanket peat alters its nature, such as by developing tree cover in drier periods and then recurring as a bog when rainfall increases. In a peat bog of this type there may be well-preserved evidence of human activity and organic material in the drier times which is later covered by renewed peat growth.