A Study of Some Escarpment Gaps in the Southern Pennines

GAPS CUT transversely across the resistant strata of a scarpland are well-known landforms. These features, whether dry wind-gaps or water-gaps followed by present-day streams, are commonly regarded as the result of superimposition from an uplifted cover of sediments.1 Alternatively, the precursors of the present-day streams have been interpreted as consequents on the slope of an uplifted marine plain, bevelled across the inclined strata.2 These interpretations can both be termed hypotheses of subsequent strike development, as they share the deduction that strike lowlands are hollowed out subsequently by headward erosion. In a third, contrasting, interpretation, transverse gaps are seen as the subsequent developments, as an older strike stream is dismembered by headward erosion across a divide.3 Such a scheme can be distinguished as a hypothesis of prior strike development, whilst all three can be referred to collectively as cyclic hypotheses. These cyclic hypotheses, however, leave unexplained and sometimes ignore escarpment features frequently associated with transverse gaps in the southern Pennines. These features, summarized diagrammatically in Figure I, show distinct contrasts with conditions on an uplifted coastal plain, as deduced by W. M. Davis.4 The following section of the account describes these features, citing examples from the southern Pennines, especially from the Errwood area on the west limb of the Goyt Trough syncline. Figure 2 illustrates the geology and relief of this area. The account also uses illustrations from well-documented scarplands, as the transverse gaps in the southern Pennines are often little known or undescribed

Escarpment · Geomorphology · Landform · STREAMS · Syncline · Tectonics · Trough (economics · Aeolian processes and effects · Geological formations and processes · Geology · Geology and Paleoclimatology Research · Paleontology