Lake sedimentological and ecological response to hyperthermals : Boltysh impact crater, Ukraine

Acknowledgements Initial drilling of the Boltysh meteorite crater was funded by Natural Environment Research Council (NERC) grant NE/D005043/1. The authors are extremely grateful to the valuable scientific contributions of S. Kelley and I. Gilmour. The constructive and critical reviews by M. Schuster and an anonymous reviewer greatly helped to improve this manuscript.Peer reviewedPostprin

Volcanic forcing from two sides : Drainage and plant ecosystem development in the Columbia River Flood Basalt Province, Washington State

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Organic geochemistry of the Boltysh impact crater, Ukraine

The Boltysh crater has been know for several decades and was originally drilled in the 1960s - 1980s in a study of economic oil shale deposits. Unfortunately, the cores were not curated and have been lost. However we have recently re-drilled the impact crater and have recovered a near continuous record of ~400m of organic rich sediments deposited in a deep isolated lake which overly the basement rocks spanning a period ~10 Ma. The Boltysh impact crater, centred at 48°54–N and 32°15–E is a complex impact structure formed on the basement rocks of the Ukrainian shield. The age of the impact is 65.17±0.64 Ma [1]. At 24km diameter, the impact is unlikely to have contributed substantially to the worldwide devastation at the end of the Cretaceous. However, the precise age of the Boltysh impact relative to the Chicxulub impact and its location on a stable low lying coastal plain which allowed formation of the postimpact crater lake make it a particularly important locality. After the impact, the crater quickly filled with water, and the crater lake received sediment input from the surrounding land surface for a period >10 Ma [2]. These strata contain a valuable record of Paleogene environmental change in central Europe, and one of very few terrestrial records of the KT event. This preeminent record of the Paleogene of central Europe can help us to answer several related scientific questions. What is the relative age of Boltysh compared with Chicxulub? How long was the hydrothermal system active for after the impact event? How did the devastated area surrounding the crater recover, and how rapid was the recovery? The first sediments to be deposited in the crater lake were a series of relatively thin turbidites, the sediments then become organic rich shales and oil shales. Within the core there is ~400 m of organic rich shales/oil shales spanning a period of ~10 Ma some of which contain macrofossils such as ostracods, fish and plant fossils. Preliminary palynological studies suggest initial sedimentation was slow after the impact followed by more rapid sedimentation through the Late Paleocene. Hydrocarbons extracted from these samples are commonly dominated by terrestrial n-alkanes (Fig 1), Hopanes (including 3-methylhopanes) and steranes are also abundant and indicate the immaturity of the samples. The immaturity of samples is also evident from the abundance of hopenes, sterenes and oleanenes especially in the upper section of the core. In some of the oil shales the hopenes and sterenes are the most abundant hydrocarbons present. There is variation in the distribution of hydrocarbons/biomarkers and palynology throughout the core caused by changing inputs and environmental conditions

Reconstruction of drainage evolution in a Large Igneous Province : Intra-basaltic sedimentation in the Columbia River Basalt Province, Washington State, USA

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Miocene vegetation in the Columbia River Basalt Province, Washington State, USA

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The development of fluvial environments within volcanic terrains : the Miocene Columbia River Basalt Province (Washington State, USA) as a case study

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The applicability of Raman spectroscopy in the assessment of palaeowildfire intensity

Acknowledgments We would like to thank Maria-Ara Carballo-Meilan, Ilse Kamerling and Colin Taylor for their kind assistance with the procurement and operation of pyrolysis equipment. The use of Calluna vulgaris material in this study was informed under an assessment of ‘least concern’ by the IUCN Red List of Threatened Species. This research was supported by funds from the School of Geosciences, University of Aberdeen.Peer reviewedPostprin

Oral Microbial Burden of Periodontal Pathogens among Orthodontic Patients

Objectives Many research studies involving orthodontic patients have a natural inclination to focus on changes in levels of cariogenic pathogens after bracket placement, and very few studies examine the role of changes of periodontal pathogens – particularly among adult patients. Interestingly, recent evidence suggests that increased levels of a specific periodontal pathogen, Fusobacterium nucleatum, may elevate risk for development of colon cancer in adults through direct pathways. Based upon this new evidence, the objective of the current study was to screen saliva samples taken from orthodontic patients to determine the prevalence of periodontal pathogens, including F. Nucleatum, T. denticola, and P. gingivalis. Methods Following an OPRS (human subjects) approved protocol, saliva samples were collected at random from orthodontic and non-orthodontic patients over the course of several weeks. DNA was subsequently isolated from these samples and screened using polymerase chain reaction (PCR) for the presence of Fusobacterium nucleatum, Treponema denticola and Porphyromonas gingivalis, using primers designed specifically to distinguish these micro-organisms. Results A total of 310 samples were collected and analyzed. The 159 orthodontic samples revealed lower overall levels of the three oral pathogens tested, compared to the 151 non-orthodontic samples. More specifically, the levels of F. nucleatum, T. denticola, and P. gingivalis were detected in 38.4%, 27.7% and 36.5% of orthodontic patients compared with 39.1%, 35.8%, and 40.4% in non-orthodontic patients respectively. Conclusions These findings support previous evidence that a significant proportion of orthodontic clinic patients may harbor periodontal pathogens at high levels. These results are much higher than previous studies which found periodontal pathogens including P. gingivalis in about 39.1% of clinic patients. Although high levels of periodontal pathogens were observed in the orthodontic sample, interestingly, even higher levels were observed in the non-orthodontic sample, when comparing the two. These findings are important when determining oral health changes that adult patients within this population may face during orthodontic treatment. These findings suggest that orthodontic patients could benefit from not only routine dental and periodontal treatment, but also from increased education and awareness regarding the possibility of increased risk for the development of colon cancer among some patients

Stratigraphic Overview of Palaeogene Tuffs in the Faroe-Shetland Basin, NE Atlantic Margin

Acknowledgements We are very grateful to PGS for generously donating seismic datasets. Seismic interpretation was carried out using IHS Kingdom software, and wells were downloaded from the UK Oil & Gas Common Data Access Welllog interpretation was conducted using Schlumberger Techlog software. D.W. would also like to thank C. Telford for insights regarding the identification of tuffs in ditch cuttings and Total (UK) for material concerning the Vaila Formation. Attendees of VMRC workshops from academia and industry provided important insights into the stratigraphy of the FSB. Finally,D.W.would like to acknowledge the late Robert Knox, without whom our knowledge of North Atlantic explosive volcanism would be considerably poorer. The reviews of P. Reynolds and J. Ólavsdóttir greatly improved the paper. Funding This work is part of D.W.’s PhD research, which is funded by a University of Aberdeen College of Physical Sciences Scholarship.Peer reviewedPostprin