Polygenetic origin of limestone pavements in northern England

摘要

The Ingleborough and Great Asby Scar National Nature Reserves in northern England contain some of the finest examples of limestone pavements in Britain. These pavements lie within the Devensian ice limits and are usually described as a glaciokarst. Undoubtedly, some pavements were formed contemporaneously with the flow of Devensian ice but there is now evidence to suggest that some pavements were also exhumed by ice and are part of a widespread Asbian-OLower Brigantian Stage palaeokarst. There is also evidence to suggest that some pavements are part of a glacially truncated palaeokarst. In the light of this evidence it is suggested that there are genetically four types of pavement in northern England namely: glacially eroded joint-dominant pavements; glacially exhumed calcrete-dominant pavements without palaeokarst; glacially exhumed calcrete-dominant pavements with palaeokarst; glacially truncated palaeokarst.