Preservation of a heavily bored belemnite rostrum from the upper Maastrichtian of north-east Belgium     

Stephen K. Donovan  John W.M. Jagt  Mart J.M. Deckers  Johan Laffineur 《Proceedings of the Geologists' Association. Geologists' Association》2019,130(2):227-231

The robust calcite rostra (or guards) of belemnites were attractive substrates for some boring organisms in the Mesozoic. The rostra of belemnitellid coleoids are common at certain levels within the Gulpen and Maastricht formations of the extended type area of the Maastrichtian Stage (Upper Cretaceous) in the south-east Netherlands and north-east Belgium. A range of episkeletozoans have been reported from these substrates hitherto. A new specimen preserved as a natural mould in flint from the province of Liège, north-east Belgium, is distinctive, preserving a dense three-dimensional infestation of long, slender, unbranched and unsculptured borings of constant diameter, Trypanites? isp. These may be the spoor of polychaetes. Variations in diameter between borings suggests that the traces in this specimen may represent four separate infestations.  相似文献   

The Enlightened Mr. Parkinson by Cherry Lewis,Icon Books,London, 2018, xii+306 pp., Pbk., ISBN: 978-1-78578-336-4. £9.99.     

Stephen K. Donovan 《Proceedings of the Geologists' Association. Geologists' Association》2019,130(5):654

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Basic palaeontology by Michael Benton and David Harper,Addison Wesley Longman,Harlow, Essex, 1997. No. of pages: xv + 342. Price: £22.99 (paperback). ISBN 0‐582‐22857‐3.     

Stephen K. Donovan 《Geological Journal》2001,36(1):88-88

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Reproductive ecology and abundance of the sand tiger shark, Carcharias taurus, from the southwestern Atlantic     

Lucifora  Luis O.; Menni  Roberto C.; Escalante  Alicia H. 《ICES Journal of Marine Science》2002,59(3):553-561

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EPA's CLEANUP 2000: Reforms to the RCRA Corrective Action Program     

Kevin Donovan 《Ground Water Monitoring & Remediation》1998,18(4):58-60

"EPA has initiated CLEANUP 2000, which includes a number of reforms to the RCRA Corrective Action Program to help increase the pace of cleanups."  相似文献   

A diverse terrestrial fauna in the Pleistocene of Jamaica: the treasures of the Red Hills Road Cave     

Stephen K. Donovan  Christopher R.C. Paul 《Geology Today》2011,27(5):173-180

The thick and widespread limestones of Jamaica include many hundreds of caves of all shapes and sizes. The Red Hills Road Cave, near Kingston, is unusual for the richness of its included tetrapods and gastropods, and the exceptional, three‐dimensional preservation of terrestrial arthropods such as millipedes. This diverse assemblage consists mainly of a forest fauna that was washed into a bottle‐shaped cave, either alive or as carcasses, during tropical storms and hurricanes about 30 000 years ago.  相似文献   

Beachcombing and palaeoecology     

Stephen K. Donovan 《Geology Today》2011,27(1):25-33

Beachcombing is not just a diversion for the idle; it can provide unique data for the observant geologist. The perspicacious palaeontologist may find informative specimens either in pebbles or in unusual Recent shells that provide analogues of, for example, ancient organisms or interactions between extinct species. Examples of rare specimens from both sides of the Atlantic Ocean demonstrate how these unique data that can be used by the discriminating beachcomber.  相似文献   

Neoichnology and implications for stratigraphy of reworked Upper Oligocene oysters,Antigua, West Indies     

Stephen K. Donovan  David A.T. Harper  Roger W. Portell  Willem Renema 《Proceedings of the Geologists' Association. Geologists' Association》2014

The Late Oligocene oyster Hyotissa antiguensis (Brown) is locally common in the Antigua Formation of Hughes Point, eastern Antigua, Lesser Antilles; it was not commonly bored at that time. Its valves and shells are robust, and reworked into the shallow water near-shore environment in Antigua; it could potentially be incorporated into younger rocks. Its neoichnology includes clues that would facilitate identification of these oysters as reworked fossils. The suite of modern borings found in these specimens includes common Caulostrepsis taeniola Clarke, Gastrochaenolites isp. cf. G. turbinatus Kelly and Bromley and Entobia isp., and rare Oichnus simplex Bromley and Rogerella? isp. The latter three taxa are limited to oyster shell substrates. Of the common ichnotaxa, Caulostrepsis and Gastrochaenolites are particularly prominent in limestone clasts and limestone cemented to oyster shells, which would be an indicator of reworking if found in a post-Oligocene lithified deposit. Caulostrepsis and Gastrochaenolites are relatively less common in oyster shells and valves, and in many specimens are seen to terminate against the shell. Entobia is the only common boring limited to the shell substrate. The fidelity of preservation of modern borings is also superior in limestone clasts. This suite of borings is comparable with those found in the Neogene of the Antillean region.  相似文献   

Eurypterids illustrated: The search for prehistoric sea scorpions by Samuel J. Ciurca,Jr. PaleoResearch,Rochester, New York, 2010. No. of pages: 30. ISBN 978‐1‐450736566 (paperback)     

Stephen K. Donovan  Mark Donovan 《Geological Journal》2011,46(6):662-662

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Defining trace-element alteration halos to skarn deposits hosted in heterogeneous carbonate rocks: Case study from the Cu–Zn Antamina skarn deposit,Peru     

A. Escalante  G.M. DippleS.L.L. Barker  R. Tosdal 《Journal of Geochemical Exploration》2010

The presence of geochemical anomalies, defining haloes around hydrothermal ore deposits, can be used to vector towards mineralization, or identify ore bodies buried at depth. Several important types of ore deposits, including skarn deposits, are often hosted within carbonate-rich sedimentary rocks. Identifying anomalous trace-element concentrations in carbonate rocks is complicated by variable lithology (i.e. siliciclastic component) and volume loss during hydrothermal alteration. In this study of the world-class Antamina skarn deposit in Peru, we use the ratio of metals:immobile elements (e.g. La, Al₂O₃) to differentiate genuine and false geochemical anomalies in limestones and marbles surrounding the skarn deposit. Unaltered limestones are used to define threshold values for metal:immobile element ratios (through use of the median value ± 2 median absolute deviations). Genuine anomalies are identified when metal concentrations exceed those predicted using median + 2 median absolute deviations. In addition, comparison of “four acid” and lithium-borate fusion analytical techniques reveals that the lower cost four-acid techniques give reliable results. Our approach can be used to identify geochemical anomalies and halos related to hydrothermal alteration of carbonate-rich rocks, which have direct application to skarn deposits.  相似文献