Carboniferous rocks within this area occupy the region contiguous with the northern
Pennines to the north (Chapter 12) and the Peak District to the south (Chapter 10). All
of the stages of the Carboniferous are present at outcrop, with the exception of
Stephanian strata, which are absent. The oldest Tournaisian strata crop out within the
Craven Basin, and are represented by ramp carbonate rocks (Bowland High Group)
deposited on the Bowland High and adjacent Lancaster Fells and Bowland sub-basins.
These carbonate rocks are overlain by mainly Visean hemipelagic mudstone and
carbonate turbidites (lower part of Craven Group). To the south of the Pendle Fault
System (Fig. 11.1), further platform carbonate rocks are proved in the subsurface
above the Central Lancashire High (Trawden Limestone Group) and the Holme High
and Heywood High (Holme High Limestone Group). These carbonate rocks, which
developed during the Tournaisian to late Visean, are known only from well records
and geophysical information and are not divided into formations. During the Visean,
the platform carbonate rocks pass laterally into more basinal successions in the
Harrogate, Rossendale and Huddersfield sub-basins (Craven Group). The
lithostratigraphical nomenclature for the Tournaisian and Visean strata is that of
Waters et al. (2009), adapted from Riley (1990)