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has dissolved away in numerous locations such as at Pwll Byfre and resulted in the wholesale collapse of the sandstone beds above it. It is thought that the sandstone has been let down several hundred feet in places due to the removal by solution of limestone strata.
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more or less intact or they may assume a chaotic structure in the process of collapse or some intermediate state of disruption.
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Examples of foundered strata are found along the northern margin of the outcrop of the
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in its maps and geological memoirs, and indeed by other authors, to describe
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This article about a specific United
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images of Pwll Byfre and surrounding area on
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of underlying strata. Foundered strata may retain original
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