The Millstone Grit (namurian) of the southern pennines viewed in the light of eustatically controlled sequence stratigraphy

Abstract

The overall lithological succession in the Millstone Grit of the southern Pennines was most probably controlled by glacial-eustatic sea-level oscillations and may be interpreted in terms of the systems tracts of sequence stratigraphy. Bands containing thick-shelled goniatites represent 'condensed sections' formed at times of maximum flooding. Turbidite-fronted deltas, marking major basin-filling episodes, resemble 'lowstand systems tracts'. However all sand influxes did not necessarily occur during lowstands. Millstone Grit sheet deltas and elongate deltas resemble lobate and birdfoot deltas in Recent 'highstand systems tracts'. The prograding fluviodeltaic complexes at the tops of some major turbiditefronted deltas were braid deltas. So was the sheet-like channel complex of the Rough Rock at the top of the Millstone Grit, but this was probably part of a 'highstand systems tract'. KEY WORDS EPR Sequence stratigraphy Systems tracts Eustasy Allocycles Braid deltas Northern England

Discrimination of regionally extensive coals in the Upper Carboniferous of the Pennine Basin, UK using high resolution sequence stratigraphic concepts

“…Previous workers have studied the sedimentology of these stratigraphic units (Collinson & Banks 1975;Miller 1986;Bristow 1988;Bristow & Meyers 1989), whereas the most recent research has started to apply the concepts of sequence stratigraphy to the succession (Read 1991;Church 1992;Maynard 1992). The generalized stratigraphy of the group is summarized in Fig.…”

The Roaches and Ashover Grits: sequence stratigraphic interpretation of a ‘turbidite-fronted delta’ system

“…However, as pointed out by Collinson et al (1992), some`turbidite-fronted' deltas such as that in the Kinderscoutian of north Derbyshire must have had very complicated sedimentary histories and associated sea-level curves, a view supported by Read (1993) and Hampson (1994). Martinsen's (1993) study of the early Namurian succession in the Craven area, which includes a`turbidite-fronted' delta, broadly supported the conclusions of Read (1991). In a later discussion of the Craven area Martinsen et al (1995) drew a distinction between a shelf-edge sequence, in which a lowstand turbidite fan developed, and a ramp sequence which produced a falling stage systems tract but no turbidite fan.…”

“…However, it is also necessary to explore other possibilities, and in particular to examine the likely impact of sea-level¯uctuations on the genesis of deep-water sandstones. Read (1991) was the ®rst to provide an alternative to the traditional model by suggesting that the turbidites of the Central Pennines Namurian accumulated in lowstand fans. Accepting this as a possibility, two other models can be considered.…”

“…These include very unusual giant cross-beds, interpreted as the deposits of alternate bars (McCabe 1977;Jones and McCabe 1980). Read (1991) was the ®rst to suggest that the`turbidite-fronted' deltas might be lowstand systems tracts of the Exxon sequence stratigraphic model of Van Wagoner et al (1988). However, as pointed out by Collinson et al (1992), some`turbidite-fronted' deltas such as that in the Kinderscoutian of north Derbyshire must have had very complicated sedimentary histories and associated sea-level curves, a view supported by Read (1993) and Hampson (1994).…”

Investigations on the shale oil and gas potential of Westphalian mudstone successions in the Campine Basin, NE Belgium (well KB174): Palaeoenvironmental and palaeogeographical controls

“…These sediments were deposited in cycles from marine (euryhaline or stenohaline) over brackish to non-marine and back to marine (Paproth et al, 1996). This cyclicity might reflect the autocyclic dynamics of the sedimentary system for small-order cycles (Delmer, 1952), but also reflects a glacio-eustatic overprint for large-order cycles (Ziegler, 1989;Read, 1991;Heckel, 1994). Marine and brackish incursions occurred more frequently during the Westphalian A, when deposition took place in a lower delta plain environment.…”