Williams, HarrietDuffin, Christopher J.Hildebrandt, ClaudiaParker, Adam...
18页
查看更多>>摘要：Westbury Garden Cliff has been a noted site for Rhaetian bone beds for over a century. It is known especially as a source of excellently preserved bones of the small marine reptile Pochystropheus as well as other reptiles, and fishes. Further it is the type locality of the Westbury Formation, the lower half of the British Rhaetian (Penarth Group). It was also featured in a debate over lateral equivalence of the basal Rhaetian bone bed, with supposedly 5-6 m of pre-basal bone bed deposition. However, the bone beds at different localities are unlikely to be of exactly the same age, and the succession at Westbury Garden Cliff lacks the erosive base of the Westbury Formation seen elsewhere and so presumably started later, perhaps reflecting progressive inundation of the Welsh High, the nearest land. However, the main bone bed occurs in lenses up to 20 cm wide, and may represent hummocky cross stratification, evidence of storm bed deposition. Trace fossils in several sandstones include Selenichnites and Crescentichnus, evidence of shallow-water limulids ploughing the sediment for food, Lokeia, the living burrows of bivalves, and Chondrites burrow systems, suggesting subsequent stability of the sandstone beds. (C) 2022 The Geologists' Association. Published by Elsevier Ltd. All rights reserved.
查看更多>>摘要：Large, ramified burrow systems with a thick lamination and bulbous enlargements are common in the Upper Greensand Formation (Albian) of Ventnor, Isle of Wight. From there, these trace fossils were first described by Thomas Webster more than two centuries ago. Although also characteristic outside their area of original description, these structures and Webster's fabulous documentation have fallen into oblivion and only recently were assigned to the ichnogenus Lamellaecylindrica. The two included ichnospecies, L. paradoxica and L. ludwigae reflect different behaviours of their trace maker (possibly a holothurian) in adaption to variations in the sedimentary conditions and current energy. A comparison of the associated ichnofauna with that of the Upper Greensand Formation at Lyme Regis, about 100 km to the west, reveals subtle but significant differences in the trace-fossil distribution, ichnodiversity and ichnoabundance, indicating a proximal (lower shoreface to offshore transition) to distal (inner shelf) depositional trend from west to east. Given the total bioturbation of the greater part of this shelf succession, these subtle variations in the ichnofauna provide valuable information for interpretation of the depositional environment and differences in the energy level where primary sedimentary structures are absent. (C) 2022 The Geologists' Association. Published by Elsevier Ltd. All rights reserved.
查看更多>>摘要：A newly discovered ammonite of the genus Hyperlioceras from the Lincolnshire Limestone Formation of Eastern England enables the biostratigraphical position of the principal building stone of Lincoln Cathedral: the 'Silver Bed' variant of Lincoln Stone (Lower Lincolnshire Limestone) to be precisely dated as subsectum biohorizon of the Lower Bajocian, Disrites Zone. Ammonites are extremely rare in this formation thus the impetus to record it here and provide a firm date for strata in which it occurred following its discovery. The lithostratigraphical provenance of the specimen is briefly discussed and evidence provided to support the conclusion. (C) 2022 The Geologists' Association. Published by Elsevier Ltd. All rights reserved.
查看更多>>摘要：Crinoidal debris is common from the basal parts of the open marine Khuff Formation in Oman; yet, little is known about the diversity and affinities of this fauna. Exallocrinus khuffensis n. gen., n. sp. is described from this unit, and is the first crinoid crown from outcrops of the Wordian, Lower Khuff Member, in the northern Huqf region of Oman. This new crinoid is among the youngest Paleozoic crinoids known, yet it has a combination of more stemward and crownward characters. Because of the uncertainties concerning the latest Paleozoic and earliest Mesozoic crinoid phylogeny, Exallocrinus n. gen. is questionably assigned to the Ampelocrinidae. (C) 2022 The Geologists' Association. Published by Elsevier Ltd. All rights reserved.
查看更多>>摘要：Sun Hole, a small fissure cave on the north side of Cheddar Gorge, Somerset, is best known as the site where late Upper Palaeolithic artefacts are associated with human and other mammal remains that immediately pre-date the Lateglacial interstadial. These remains from the upper levels (Unit I) overlie sediments (Unit II) that are thought to have accumulated during a full glacial period, below which are sediments (Unit III) attributed to an interglacial stage. The extinct land snail Retinella (Lyrodiscus) sp., which in Britain was only known from the Hoxnian Stage, had previously been recovered from Unit Ill. The interglacial at the base of the sequence was therefore assigned to the Hoxnian Stage (Marine Isotope Stage (MIS) 11,424-374 kyr). Here we provide additional analyses of samples from Unit III, which as well as containing further Retinella (Lyrodiscus), also yielded a specimen of Monachoides incarnatus, its first record from the British Pleistocene. An associated assemblage of small mammals included a few that are rare in the British Pleistocene, such as birch mouse (Sicista cf. betulina) and garden dormouse (Eliomys quercinus). The vole Lasiopodomys gregaloides and the shrew Sorex (Drepanosorex) savini do not occur as late as the Hoxnian and therefore suggest an older age in the early Middle Pleistocene. The record from Sun Hole therefore has parallels with the well-known sequence from the upper Calcareous Member in the nearby cavern system at Westbury-sub-Mendip. (C) 2022 The Geologists' Association. Published by Elsevier Ltd.
查看更多>>摘要：This paper presents a historical perspective of the discovery of, and aspects of, glendonite and ikaite, through the legacy of British mineralogists Douglas Shearman and Alec K. Smith. Much of the knowledge, literature review and synthesis presented in the following paper raises from the original work and discussions that these two key figures in mineralogy shared with the geological community both in the form of their official communications but also as informal discussions with the first author. Through our extensive review, we show that, while the link between ikaite and glendonite is now undeniable, questions remain. (C) 2022 The Geologists' Association. Published by Elsevier Ltd. All rights reserved.
Donovan, Stephen K.Kabrna, PaulSavill, Jeremy J.Tenny, Andrew...
2页
查看更多>>摘要：Correcting proofs are a necessary evil of academic publishing and the last chance for the author(s) to spot any gremlins in the text, either those errors that were overlooked at the time of submission or those that were introduced at the typesetting stage. Proofs of Donovan et al. (2021) were corrected, and errors in the typesetting of Tables 1 and 2 indicated. The tables in the version that appeared on the journal's website were still incorrect. The senior author alerted the Editor-inChief to this oversight, but the publication in hard copy was still wrong. Below, we reproduce Tables 1 and 2 with the correct assignation of certain references.
NSTL
Elsevier