Body and trace fossils of Ediacaran affinity are described from strata of the late Neoproterozoic Longmyndian Supergroup exposed near Church Stretton, Shropshire, UK. The almost spherical soft-bodied Ediacaran fossil Beltanelliformis brunsae Menner occurs rarely in the Burway Formation, but much smaller, simpler, discoidal structures are common in both the Burway and Synalds formations and are referred to Beltanelliformis minutae sp. nov. Similar discoidal structures, but with a distinct central depression, are included in Intrites punctatus Fedonkin and are common at several horizons. Two blocks with numerous examples of Medusinites aff. asteroides (Sprigg) Glaessner & Wade were recovered from the Burway Formation. The purported Ediacaran body fossil ‘Arumberia’ Glaessner & Walter is common at several horizons but its biogenicity is not accepted herein. ‘Arumberia’ is thus treated along with evidence for microbially bound sediment surfaces or matgrounds that have been suggested by several authors to be necessary for some types of Ediacaran preservation. The assemblage of simple trace and body fossils along with matgrounds is typical of latest Neoproterozoic time, though some elements range into the Phanerozoic.

The Longmyndian Supergroup is an approximately 6500 nl thick sedimentary sequence of late Precambrian age. Major unconformities within this sequence are lacking. The Longmyndian Supergroup can be divided into four facies associations: (1) turbidite, (2) subaqueous delta, (3) alluvial floodplain, and (4) braided alluvial. These are organized into a single, broadly upwards-coarsening, progradational sequence, with the turbidite association at the base and the braided alluvial association towards the top. The sediments are interpreted to have been deposited in a forearc, or possibly interarc, basin which lay to

Major revisions are proposed to the stratigraphy of the late Precambrian Longmyndian Supergroup of the Welsh Borderland. The stratigraphic relationship between it and the adjacent, late Precambrian Uriconian volcanic complex is reviewed and reinterpreted. Contrary to previous belief it is proposed that the Wentnor Group of the Longmyndian Supergroup does not overlie the Stretton Group unconformably. An apparent unconformity is interpreted as the result of post‐Longmyndian tectonism. The Ragleth Tuff Formation, previously included with the Uriconian volcanic complex, is argued to be part of the Longmyndian Supergroup. The Helmeth Grit Member, previously thought to be the base of the Longmyndian Supergroup, is incorporated within the Ragleth Tuff Formation. These modifications necessitate a revision of the previously held belief that the Helmeth Grit Member is the base of the Longmyndian Supergroup which overlies the ‘Ragleth Tuffs’ of the Uriconian volcanic complex unconformably. The Ragleth Tuff Formation and the Stretton Shale Formation are thought to be faulted against the Eastern Uriconian, and the Wentnor Group is thought to be faulted against the Western Uriconian. Juxtaposition of the Longmyndian Supergroup with the Uriconian volcanic complex across faults is the result of strike‐slip movements along the Church Stretton and Pontesford‐Linley fault systems. Lithological and petrographical evidence suggests that the Longmyndian Supergroup is partly coeval with, and partly younger than, the Uriconian volcanic complex, which acted as a source. The Willstone Hill conglomerate, previously thought to be interbedded with the Eastern Uriconian, may be a representative of the Wentnor Group which overlies the Eastern Uriconian unconformably. As such, it may represent a late onlap of Longmyndian sediments onto the Eastern Uriconian at the margins of the Longmyndian basin. A new formation, the Linley Formation, is recognized. This occurs as fault‐bounded slivers and lenses within the Pontesford‐Linley fault system, and correlation with the rest of the Longmyndian is uncertain.

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Three cored sandstone megabeds of Tertiary (late Palaeocene) age from two quadrants in the Central Graben of the North Sea are discussed. The megabeds are upwards-fining units 3–9 m thick, underlain by gravelly mudstones (1–1.4 m thick) which are interpreted as debrites. The megabeds are divided into five units (M1–M5) based on grain size and sedimentary structures, which are organized into a type vertical sequence. The basal unit M1 comprises a clast-supported mudclast conglomerate. Unit M2 comprises very coarse- to medium-grained, occasionally gravelly, sandstone which is horizontally laminated to cross-stratified. Unit M3 is the thickest unit (2–4 m) and is a laminated, upwards-fining, medium- to fine-grained sandstone with occasional cross-lamination. Unit M4 is a fine- to very fine-grained sandstone characterized by disturbed lamination and water-escape structures. Unit M5 is an upwards-fining silty sandstone to siltstone characterized by discontinuous, irregular, and locally overfolded laminae. The megabeds are interpreted as having been deposited by turbidity currents. There are some similarities to Bouma sequences and high-density turbidite sequences, but massive sandstone is notably absent. The megabeds are associated with mudstones and debrites and only occasional thin turbidites, and as such they are not part of an organized sequence of turbidites. The beds are notably much thicker than those above and below, and lithologies are distinct from those of the surrounding sediments. These features are comparable to those of ‘megaturbidites’ as defined by Bouma. The debrite which immediately underlies the megabeds is significant in that this relationship is also a common feature of megaturbidites. The debrite is thought to represent slope failure which immediately preceded megabed deposition. A hypothesis is presented of earthquake-induced catastrophic slope failure, debrite deposition and associated megaturbidite generation. Such sandstone megabeds are thought to be widespread sheet-like deposits. They are exploited as a hydrocarbon reservoir in two of the wells discussed.