SPPC 2019 Isle of Wight
SPPC 2019 Isle of Wight
Controlled exsiccation of fossilised remains in waterlogged marl: Slowly Slowly Dryee Squiddie, Allington-Jones
Palaeontological preparation facilities in UK universities: the north south divide? Challands, Brusatte & Wood
Cold climate collection of Cretaceous creatures in Canada, Henderson
13 years of preparing Danish fossils, a retrospective, Osbæck
Controlled exsiccation of fossilised remains in waterlogged marl: Slowly Slowly Dryee Squiddie
LU ALLINGTON-JONES
The Natural History Museum, Conservation
A fossil from a squid-like animal, preserved in Lower Jurassic argillaceous limestone or marl, was collected on the 8th March 2019 from Lyme Regis beach. The collectors kept the specimen wet by wrapping it in newspaper and plastic, and transported it to the Conservation Centre at the Natural History Museum in London (UK). Conservators partially immersed the block in water, with a few drops of thymol to prevent mould growth, whilst tests on samples of the matrix were undertaken. Two consolidants were selected from the field of waterlogged archaeological artefact conservation: Primal WS24 and PEG 400. Untreated and consolidated samples were variously dried rapidly in ambient lab conditions or dried slowly within Dartek C-917 semi-permeable cast nylon film microenvironments. Both consolidation and slow drying proved beneficial but insufficient to prevent cracking entirely. A double layer of film was then considered, to slow the drying-time even further. The entire specimen block was then consolidated by immersion in 10% and then 33% Primal WS24 before slowdrying in a double-layer Dartek C-917 film microclimate. Primal WS24 was selected in preference to PEG 400 because the former would be compatible with Paraloid B72 in acetone (if future remedial conservation becomes necessary). After drying, parts of the surface of the block were prepared using a split-V ultrasonic tool, to expose more of the nacre layer, and the lower half of the block was removed using rotary tools to minimise vibration.
Palaeontological preparation facilities in UK universities: the north south divide?
TOM CHALLANDS * , STEPHEN BRUSATTE & RACHEL WOOD
University of Edinburgh, School of Geosciences
Palaeontological preparation facilities in university departments are sadly often lacking and where present unfortunately frequently do not have a permanent member of staff or a trained preparator to manage the facilities or conduct preparation. With micro CT-scanning becoming the preferred method of fossil analysis alongside ‘digital preparation’ the need, or perhaps desire, to actively maintain a program of physically preparing fossil specimens may not be regarded so importantly. Information from all UK universities involved in active palaeontological research shows that most institutions do have some form of rudimentary preparation facilities but those that do have an active palaeontological preparation program are not evenly distributed geographically. We announce a new palaeontology preparation facility in the University of Edinburgh, School of Geosciences that represents the only such facility in a Scottish university. As part of the PalAlba consortium of academic scientists, conservation specialists, and collectors working together to recover, record and research fossils from Scotland, and our aim is to provide a facility for students to develop palaeontological preparation techniques alongside the theoretical side of palaeontological research. We present some examples of material that has been processed in this new facility and describe the set-up for this preparation.
A combination of air abrasion and ultrasonic preparation reveals fine details ahead of scanning electron microscopy, in fossil ophiuroids
MARK R GRAHAM * 1 & TIMOTHY A M EWIN 2
1 - Natural History Museum, The Conservation Centre, 2 - Natural History Museum, Earth Sciences Dept
Multiple well preserved fossil ophiuroids (brittle stars) within blocks of consolidated sandy clay from the Atherfield Clay Formation of the Isle of Wight, were fully exposed to facilitate taxonomic study by scanning electron microscopy (SEM).Their preparation required the removal of covering matrix; complicated by the entanglement of the arms of multiple specimens, the need to retain delicate taxonomically important spines and dermal plates, as well as exposing plate boundaries whilst minimising any damage to the plate surfaces (stereomes).
The specimens were also small; discs varied from 2mm to 10mm with arms up to 20 mm in length. Thus air abrasion was undertaken under a stereoscopic microscope with illumination. The optimal abrading set-up was sodium bicarbonate No.4 particle size (50 microns) delivered at 2.5bar/35 p.s.i. via a 0.75mm diameter air abrasive nozzle. The areas surrounding the specimens’ arms were trenched by air abrasion to reveal the surfaces and sides; effectively mini-pedestalled in relief on the blocks. The central discs were air abraded to expose mouthparts, ossicles, spines and plate boundaries.
Industrial metholated spirit (I.M.S.) was applied to highlight surface detail during preparation; this evaporated after a couple of minutes and left no residue on the specimens, but enabled finer details to be developed. In order to facilitate detailed SEM of individual arm plates, several pieces were removed from the blocks and placed in small, sealable plastic specimen bags with a few drops of water. The exterior of the bags were then touched with the tip of an ultrasonic pen, (Sonotec Split V) which removed the remaining matrix from the plate boundaries very effectively. This combination of techniques fully exposed all the elements required for full taxonomic study without causing severe damage and should be more widely applied to other echinoderm fossils in order to retain as much taxonomic information as possible.
Cold climate collection of Cretaceous creatures in Canada
DONALD HENDERSON
Royal Tyrrell Museum of Palaeontology
In February of 2016 staff at the Royal Tyrrell Museum of Palaeontology were informed about Early Cretaceous fossil bone that was recovered from drill core at a depth of 33.6m at the Suncor oilsand mine in northern Alberta, but were told to wait at least two years before the working face of the mine got to the drill hole. Finally, in February 2019 a crew of four was able to make the 800km drive from the Museum to the mine site. At the start of the work, daytime temperatures were in the -25C range so special precautions were going to be needed to safely and completely collect the as yet unidentified specimen. Large excavation machines were engaged for four days to dig a very large hole with the correct slopes for stability. The precise coordinates of the drill hole enabled a targeted excavation. Final exposure of the specimen was done with an electric jackhammer and hand tools. The drill hole had pierced almost the exact centre of a scattered and incomplete plesiosaur skeleton. A portable shed was temporarily used to trap warm air from a hot air source to enable plaster and glues to set and cure properly. After a week temperatures rose to around -10C, so the shed was removed. To provide daytime heat warm air was ducted directly down into the pit and blown directly on the fossil remains in the ground and the crew. At night a tarp covered the excavation and the warm air was directed and trapped under the tarp to keep the rocks and fossil warm enough for glues and plaster to behave and set properly, and to keep water warm for making plaster. The resulting plaster jackets were also kept insulated and warm during their curing process before being lifted out of the pit by heavy equipment.
13 years of preparing Danish fossils, a retrospective
FRANK OSBÆCK
Museum Salling, Conservation
I have had the privilege working with some of the most spectacular fossils found in the last decade in Denmark. Working at Museernes Bevaringscenter I Skive with specimens from Fossil og Molermuseet and Fur Museum I have had many lovely fossils on my prep. table. Fishes, turtles, birds and a couple of whales, mostly originating from the Eocene Fur Formation in northern Denmark. Once in my lab, the usual procedure was used. Hammer and chisel, diamond rotating tools and heavy pneumatic tools, using ”finer” tools when working closer to the fossil surface, dental tools, scalpels and so on. The preparation of the finest details would normally be with Acetic acid preparation buffered with Calcium orthophosphate. The preservation of the fossils often, with preserved soft tissues, would be a real challenge. I will talk about my techniques and give a broad view of my work over the years.
A new technique for sampling plant debris beds from the Early Cretaceous Wealden Group of southern England
SIMON PENN
University of Portsmouth, Earth and Environmental Science
Sampling techniques of Wealden Group plant debris beds often target specific micro-vertebrate, invertebrate or palaeobotanical assemblages. This specific targeting of microfossils inevitably results in a bias and the potential loss of important palaeontological data. A new method combining acid digestion, salt floatation and ultra-violet light illumination allows plant debris beds to be comprehensively sampled for their entire fossil assemblage. The use of traditional sieving techniques often leads to the abrasion and destruction of specimens. This multi stage method results in the retrieval of delicate, exceptionally preserved plant material, amber, plant cuticle and micro-vertebrates.