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of heavy mineral suites and palaeocurrents from Namurian and Westphalian (Millstone Grit and Coal Measures) sandstones at outcrop in eastern Derbyshire reveals four main sources of sediment supply to this part of the Pennine Basin. Three of these are known to have affected the adjacent Yorkshire Coalfield to the north, and were responsible for introducing sediment from distant source areas located in general terms to the north, west and southeast of the Pennine Basin. Northern sediment

Basinwide analysis of sedimentary facies, isopachytes and palaeocurrents for two late Marsdenian (Pennsylvanian) sedimentary cycles within part of the Millstone Grit Group, has led to a new sequence-stratigraphic interpretation for the relationships between its constituent sandstone units (currently named Huddersfield White Rock, Chatsworth Grit, Brooksbottoms Grit, Holcombe Brook Grit, Brown Edge Flags and Redmires Flags). The Bilinguites superbilinguis (R 2c 1) and Verneulites sigma (R 2c 2) marine bands related to fourth-order marine highstands show faunal variations possibly reflecting fifth-order sea-level fluctuations. The lower R 2c 1 cycle consists entirely of deep water mudstone. The overlying R 2c 2 cycle shows an upward regressive passage through pro-delta and delta-slope deposits to mouthbar and channel sandstones. The latter comprises an 'eastern inflow' of northerly provenance, the distribution of which was not influenced by the underlying basement configuration, and a 'southern inflow' sourced from the Wales-Brabant High. Falling sea-levels resulted in progressive narrowing of the fluvial pathway within the main sandstone body of the 'eastern inflow', with a concomitant increase in flow velocities and grainsize. At lowstand, this culminated in the Chatsworth palaeovalley, 25 km wide, the basal surface of which can be correlated into the interfluve areas as a leached palaeosol. Higher sandstone bodies, where developed, are of two kinds: an earlier set present outside of the palaeovalley was formed during regression, and a later set within the palaeovalley was formed as sea level rose. As part of this transgressive systems tract, a Lingula band developed across the flooded Chatsworth palaeovalley and its interfluve margin. The transgression culminated in the highstand of the Cancelloceras cancellatum (G 1a 1) Marine Band. HWR Chatsworth paper vSept07 unformatted.doc 28/07/2008 -2 -This study describes a fluviodeltaic succession within the upper part of the Millstone Grit Group, which outcrops across the central and southern Pennines, around the margins of the Peak District and in the Rossendale inlier (Fig. 1). It is based primarily on observations from surface exposures, supported by information from boreholes (Fig. 2), of the succession deposited within the Bilinguites superbilinguis (R 2c 1) and Verneulites sigma (R 2c 2) sub-biozones of the late Marsdenian Substage (Namurian Regional Stage of the Pennsylvanian) ( Fig. 3). The initial aim of the study was to determine the relationships of a number of sandstone units, namely the Huddersfield White Rock, Chatsworth Grit, Brooksbottoms Grit, Holcombe Brook Grit, Brown Edge Flags and Redmires Flags, the stratigraphical relationships of which are shown in Figure 3.Current nomenclatures for these sandstones are confusing and a simplified scheme is presented. This has led, for the first time, to an understanding of the order in which these sandstones were deposited, and in turn, to a new interpretation of the sequence stratigraphy of this classic cyclic ...

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New Nd and Sr data indicate that two isotopically distinct terrains supplied sediment to the Silesian Pennine Basin. The sources consisted of a northerly-derived fluvial system, which was responsible for much of the detritus during Namurian times, and a second major system which entered at the west and south sides of the basin. This second source, which provided material derived from the former Avalonian/Armorican and Gondwanan terranes, became more influential through the Silesian, so that by Westphalian B/C times, the central parts of the basin were being fed by systems derived from the west and south of the basin. Although the inferred source rocks are petrographically diverse their Nd-Sr signatures are remarkably similar, perhaps due to multicyclic sediment homogenization. The change in provenance may reflect early Variscan tectonic activity to the west of the Pennine Basin.

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New U–Pb ages on detrital monazite from the Carboniferous of central England show a clear difference between populations from northerly and southeasterly derived sandstones. The northern source was responsible for most of the detritus that entered the basin during Namurian times and is dominated by monazites of Scandian age with normally distributed 235 U/ 207 Pb ages averaging 420 ± 7 Ma (2 σ ). One older grain gives a Proterozoic age of 2040 ± 1.4 Ma (2 σ ). The data suggest a source region within the Scandian orogen. Southeasterly derived sediments are more heterogeneous and show a range of Variscan, Acadian, Ordovician and Sveconorwegian ages. Variscan uplifting of terranes of central Europe would provide a suitable source for this assemblage.