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An almost continuous layer of Upper Cretaceous deposits up to 1000 m thick was probably deposited across much of SW England. Phases of uplift in the late Cretaceous and early Cenozoic, each of which was followed by extensive erosion and dissolution, resulted in the removal of all except a few outliers of Chalk Group that crop out in east Devon and south Somerset. Those on the Devon coast between Sidmouth and Lyme Regis are some of the best exposed Cenomanian to early Coniacian successions in NW Europe and include the most westerly chalks preserved onshore in England. They form an integral part of the Dorset and East Devon World Heritage Site. In contrast to the Chalk of much of southern England, the older formations in Devon, the Beer Head Limestone, Holywell Nodular Chalk and New Pit Chalk, show marked lateral lithological variations that result from a combination of penecontemporaneous movements on local faults and relatively shallow-water environments close to the western edge of the Chalk depositional basin. The younger parts of the succession, the Lewes Nodular Chalk and Seaford Chalk Formations, comprise chalks that do not appear to have been greatly affected by penecontemporaneous fault movements. These formations include lithological marker beds that have been correlated with marker beds in the Sussex type area. The principal sedimentary breaks in the Devon succession cannot be correlated with confidence with eustatic changes in sea level. [ABSTRACT FROM AUTHOR]

Soft-sediment deformation structures (SSDS) including slumped beds and dewatering and diapiric structures are relatively common in the youngest part of the Triassic succession exposed on the English south coast between Seaton, Devon and Lyme Regis, Dorset. They have been attributed to fluidisation as a result of slope failure or shockwaves caused by earthquakes, storm waves or bolide impact. Few of these structures can be proved to be the result solely of a seismic event. However, diapiric structures that are restricted to a single bed and over a small area in the oldest (Rhaetian, Triassic) part of the Blue Lias formation at Pinhay Bay, Lyme Regis are morphologically similar to structures developed in present-day sediments in seismically active areas. The Pinhay Bay examples appear to have been initiated by a single event: some of them are associated with minor movements along fractures in the underlying beds. They are interpreted as the result of a small local earthquake, the last in a series of minor tectonic events in the latest Triassic that were related to the opening of the English Channel. [ABSTRACT FROM AUTHOR]

An almost complete late Permian and Triassic succession c. 1300 m thick is exposed in the cliffs between Exmouth and Lyme Regis in the Dorset and East Devon Coast World Heritage Site, U.K. All except the youngest part of the succession was deposited in terrestrial environments that include alluvial fans, aeolian sand dunes, braided rivers and playa-lakes. The succession of environments with time not only reflects the denudation of the Variscan mountains that lay to the west and south in the Cornubian and Armorican massifs, but also responses to periods of tectonic uplift and subsidence, and to long- and short-term climatic and associated biotic changes. Notwithstanding the almost continuous, readily accessible exposures in the cliffs and intertidal areas, few of the formations have yielded any age-diagnostic fossils with the result that much of the succession cannot be dated with certainty. The Permo-Triassic boundary has been placed in the lower part of the succession on the basis of magnetostratigraphy and the same method has been used to quantify some of the stage boundaries and the principal tectonic breaks in the succession. [ABSTRACT FROM AUTHOR]

The Eifelian-aged Hangman Sandstone Formation of southwest England is a unit of the 'Old Red Sandstone' that has traditionally been considered relatively barren of trace fossils. Following recent investigations, we here show it to contain the most diverse Middle Devonian non-marine ichnofauna known globally. The fluvial-lacustrine facies of its constituent Trentishoe Member contain representatives of 21 ichnogenera including Archaeonassa, Arenicolites, Beaconites, Bifungites, Circulichnis, Cruziana, Diplichnites, ? Gluckstadella, Gordia,?Halimededes,?Lockeia, Merostomichnites, Palmichnium, Petalichnus, Planolites, Polarichnus, Rusophycus, Siskemia, Spirophyton, Steinsfjordichnus , and Taenidium, as well as several microbially induced sedimentary structures. The transitional marine-influenced facies of the underlying Hollowbrook Member are less extensively exposed but contain four additional unique ichnogenera in the form of Cochlichnus, Halopoa, Phycodes , and Teichichnus , as well as further examples of Cruziana, Planolites and Taenidium. A revised ichnological assessment of the unit reveals several notable features, including the youngest known example of the arthropod refugia trace, Polarichnus , as well as a transitional trace fossil form of Diplichnites-Beaconites , demonstrating that the latter was produced by arthropods. As the Hangman Sandstone Formation records the culmination of a marine regression, its ichnofauna can be compared with that of the conformably underlying Lynton Formation, which was deposited in a sandy marine shelf setting. The ichnological differences between these units are acute, with 88% of the Hangman Sandstone Formation trace fossils being exclusive to non-marine or transitional facies. This observation sheds light on the terrestrialization process and indicates that the segregation of marine and non-marine trace fossil communities had accelerated by the Middle Devonian. Internal variability in ichnological signatures within the Hangman Sandstone Formation is also pronounced, with greater ichnodiversity and ichnodisparity in distal fluvio-lacustrine facies than in proximal fluvial facies. By viewing the depositional environment of the unit as a regionally extensive distributive fluvial system, this variability can be partly explained by a bias arising from the distribution of true substrates (bedding planes that demonstrably preserve an ancient sediment-air interface) in the unit, with such phenomena being more readily preserved in the lower energy outer reaches of the depositional system. • 25 ichnotaxa are reported from the Middle Devonian Hangman Sandstone Formation. • 88% are exclusively non-marine forms, showing Mid Devonian acceleration of terrestrialization. • Surficial trace fossils are made available by true substrates within a distributive fluvial system • Transitional forms between Diplichnites and Beaconites show the latter was formed by arthropods. • Youngest examples of Polarichnus and the first reported non-marine ?Halimededes. [ABSTRACT FROM AUTHOR]

Quartzite clasts preserving a Skolithos burrow ichnofabric are described from the Early Triassic fluvial Budleigh Salterton Pebble Beds at Budleigh Salterton, East Devon, south-west England. Representing typical Skolithos pipe rock, the clasts are provenanced with a high degree of confidence to the Ordovician of the Armorican Massif, north-west France. The tubiform biogenic structure Trachyderma serrata Salter, earlier described and documented from quartzite clasts at Budleigh Salterton and in the English Midlands, represents an atypical preservational mode of the ichnogenus Skolithos . [ABSTRACT FROM AUTHOR]

The Rhaetic Transgression, 210 Myr ago, which marked the end of continental conditions in the European Triassic, and the arrival of marine deposition, may have been heralded by the arrival of burrowing shrimps. Here we document an unusual taphonomic situation, in which classic basal Rhaetic bone bed is preserved inside a Thalassinoides burrow system at the base of the Westbury Mudstone Formation, in the highest part of the Blue Anchor Formation, at Charton Bay, Devon, UK. The fauna comprises four species of sharks and five species of bony fishes. The sharks, Rhomphaiodon (‘ Hybodus ’), Duffinselache , Lissodus , and Pseudocetorhinus are small, and include predatory and crushing/opportunistic feeders. The top predator was the large Severnichthys , typical of Rhaetian ichthyofaunas, and Gyrolepis was a smaller predator. Late Triassic bony fishes generally included many shell-crushers, and the Charton Bay assemblage is no exception, with teeth of Sargodon , ‘ Lepidotes ’, and Dapedium , the last being a rare record for the British Rhaetic. This kind of burrowed and filled contact occurs elsewhere at the base of the Westbury Mudstone Formation, and so may be a typical marker of the early phases of the Rhaetic Transgression. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a novel method to reconstruct sea-level change in coastal freshwater back-barrier marshes. Freshwater environments have long been considered to be unsuitable for the reconstruction of Holocene sea-level changes as they provide limiting, rather than precise, sea-level index points. We recorded the stratigraphy of a small beach and back-barrier coastal Phragmites (reed) marsh at Hallsands, south Devon, southwest England, using hand-drilled cores and ground-penetrating radar, and collected five new sea-level index points from the base of a Holocene peat sequence to refine the regional Holocene relative sea-level curve. We demonstrate that the samples, despite their freshwater origin, yield accurate sea-level index points as determined from the quantifiable relationship between tide levels and groundwater. By means of water-table monitoring and groundwater modelling we show that the primary controls on the water table in the marsh are: (1) stratigraphy; (2) peat permeability; and (3) recharge rates in the back-barrier marsh. The five index points document relative sea-level positions between 7200 and 2400calyr BP. Three points are in good agreement with previously collected regional data from intertidal deposits and two points usefully fill gaps in the existing reconstruction. An amended Holocene relative sea-level curve for south Devon, based on 30 data points, is presented. We conclude that the combined approach of data collection and modelling used in this paper can be applied to similar coastal settings around the world and allows the collection of sea-level index points from locations not previously thought suitable for this purpose. [Copyright &y& Elsevier]

Abstract: Lundy lies in a strategic geographical position for understanding the glacial history of the British Isles. The island bears evidence of glaciation, largely in the form of ice-moulded bedrock and glacially-transported boulders – an unusual occurrence this far south in the British Isles. Irish Sea ice penetrated the western Bristol Channel overriding Lundy from the northwest during the last phase of glaciation in this area. The results of paired terrestrial cosmogenic nuclide analyses (26Al/10Be) constrain the timing of this extensive glaciation and provide, for the first time, an age for the exposure of Lundy granite following deglaciation. The results from nine paired samples yield 26Al/10Be exposure ages of 31.4–48.8 ka (10Be) and 31.7–60.0 ka (26Al). This challenges the view that any glaciation this far south must belong to Middle Pleistocene glaciations, such as the Anglian Stage (c. 480–420 ka) and a Devensian age for the last glaciation is consistent with findings from the Isles of Scilly further south. However, the findings suggest early-mid Devensian (marine isotope stage (MIS) 4–3) glaciation of Lundy. It also implies that the island was exposed or covered for a short time by non-erosive cold-based ice at the global Last Glacial Maximum (LGM) during MIS 2 (26–21 ka). The potential exposure of the island throughout MIS 2 contrasts with the evidence from the Isles of Scilly and the Celtic Sea, which were glaciated at the LGM. [Copyright &y& Elsevier]

Synthetic musks are ubiquitous contaminants in the environment. Compartmental distributions (dissolved, suspended particle associated and sedimentary) of the compounds throughout an axial estuarine transect and in coastal waters are reported. High concentrations of Galaxolide® (HHCB) and Tonalide® (AHTN) (987–2098 ng/L and 55–159 ng/L, respectively) were encountered in final effluent samples from sewage treatment plants (STPs) discharging into the Tamar and Plym Estuaries (UK), with lower concentrations of Celestolide® (ADBI) (4–13 ng/L), Phantolide® (AHMI) (6–9 ng/L), musk xylene (MX) (4–7 ng/L) and musk ketone (MK) (18–30 ng/L). Rapid dilution from the outfalls is demonstrated with resulting concentrations of HHCB spanning from 5 to 30 ng/L and those for AHTN from 3 to 15 ng/L. The other musks were generally not detected in the estuarine and coastal waters. The suspended particulate matter (SPM) and sedimentary profiles and compositions (HHCB:AHTN ratios) generally reflect the distribution in the water column with highest concentrations adjacent to sewage outfalls. [Copyright &y& Elsevier]

Summary: This study examined stream water quality across a range of catchments which are representative of the key environments and land uses of rural south-west England. These catchments included: (a) an acidic upland headwater catchment, rising on the moorlands of Dartmoor, with low-intensity sheep rearing; (b) a headwater catchment rising on the weathered granite lower slopes of Dartmoor, with cattle farming; (c) a lowland headwater clay catchment with sub-surface drainage and high intensity livestock farming, fodder crop cultivation, and hard-standing/slurry storage; and (d) the main River Taw, a lowland river system receiving drainage from a range of tributaries, exemplified by the above catchment types. Variations in water chemistry and quality were observed along an upland–lowland transition, from headwater streams to the main river channel. Within the livestock-dominated headwater streams, total phosphorus (TP) was dominated by particulate phosphorus (PP). These PP concentrations appeared to be mainly linked to two sets of processes: (1) in-stream sediment precipitation with sorption/co-precipitation of phosphate and/or localised in-channel mobilisation of sediment (by cattle or channel-clearing operations) under low flow conditions, and (2) sediment erosion and transportation associated with near-surface runoff during storm events. Under baseflow conditions, in-stream and/or riparian processes played a significant role in controlling general nutrient chemistry, particularly in the headwater streams which were heavily impacted by livestock. [Copyright &y& Elsevier]

Abstract: Given the growing emphasis being placed on water conservation in and around the home by water companies, there is a pressing need to identify the characteristics of the water saver so that policy makers can more accurately target initiatives for water conservation. This paper examines the social, attitudinal and behavioural composition of water saving activities using a sample of 1600 households from Devon. The research sought to examine the links between water saving, energy conservation, green consumerism and waste management in and around the home. Accordingly, the extent to which water saving can be placed within a behavioural context that incorporates different environmental behaviours is discussed. The data relating to water saving are then analysed and four different types of individual are defined, according to their behavioural characteristics. These are examined in the context of their demographic composition and a range of attitudinal factors. The policy implications of the research are described throughout the paper. [Copyright &y& Elsevier]

Abstract: This paper examines the structure of waste reduction, reuse and recycling behavior within the context of wider research on environmental action in and around the home. Using a sample of 1265 households from Devon, England, the research examined a range of environmental behaviors, focusing on energy saving, water conservation, green consumerism and waste management. Using factor analysis, the data were analysed to examine how the different behavioral variables related to each other. The research found that waste management behaviors were evident in two of the three factors identified. These related not only to recycling or reuse behaviors but also to consumption practices, such as purchasing recycled products. However, an analysis of the frequency of each of these factorially-defined behaviors revealed that recycling was still the activity most practised by individuals, with reduction behaviors least popular. This was explored further by the use of cluster analysis, which defined four distinctive behavioral types with different demographic characteristics. Accordingly, the research demonstrates that examining waste management behaviors within the context of wider environmental actions can be of use. [Copyright &y& Elsevier]