Admissions > PhD by research > Research Projects > Vertebrate taphonomy of the Jehol Group (Early Cretaceous), NE China

Vertebrate taphonomy of the Jehol Group (Early

Cretaceous), NE China

Supervisors: Professor Michael J Benton, Dr Stuart Kearns and Dr Patrick Orr (University College Dublin)

This project is fully funded as part of an existing NERC-funded project.


This project offers an astonishing opportunity for a student interested in field-based sedimentology and taphonomy, both in the field and laboratory. The Jehol Group (Early Cretaceous) of NE China (Liaoning, Hubei, Inner Mongolia provinces) has become famous in the past twenty years as the source of spectacular fossils, including dinosaurs with feathers, diverse early birds, other reptiles, amphibians, fishes, invertebrates, and plants. These illustrate some 10-15 million years of the evolution of lake systems, punctuated by volcanic eruptions, and the fossils famously show exquisite preservation of soft tissues.

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Key questions to be solved by the PhD student include: why are such a wide array of fossils so exquisitely preserved; are there particular sedimentological or geochemical correlates of exceptional preservation, especially of individual tissue types; how do the fossils preserved in volcanic ash differ from those in lacustrine muds; how completely do the assemblages represent living faunas of the time; how extensive are original sultrastructures and biochemicals in the fossils?

This PhD is an integral part of a funded NERC project on ‘Evolution of feathers and colours in birds and dinosaurs’, which begins in 2012, and the student will collaborate throughout with the team. Through this project, we collaborate with senior scientists at the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) in Beijing, and have access to all field sites and specimens.

The project will involve fieldwork in NE China, where the student will make standard sedimentary logs through long sections, collect samples for petrological study, and describe as wide a variety of relevant sedimentary settings as possible. Laboratory study will focus on interpreting the sedimentology and taphonomy of allkinds of fossiliferous sites.

For selected vertebrate taxa (including, but not solely, bird and dinosaur taxa) the aims are to (a) determine physical taphonomy including modelling patterns of skeletal disarticulation; (b) determine extent and modes of soft tissue preservation in various taxa; (c) systematically excavate one or more fossil-rich localities to place taphonomic models based on the fossils in sedimentological context; (d) assess taphonomic models that emphasise mass mortality events, entombment in volcanic ash and origin of opisthotonic postures of allochthonous taxa; (e) confirm how widespread melanosome preservation is in other taxa, e.g. pterosaur hair, fish eyes, etc.

height="245" The extensive museum collections include a wide spectrum of taxa in different preservational states from all key localities. A census study of thousands of specimens in the IVPP collections documenting the detailed taphonomic history of taxa, cross-referenced against locality and age, will cover lithology, posture, articulation and completeness of specimens, and presence and absence of soft tissues. Previous reports of soft tissue preservation in Jehol vertebrates have over-emphasised the presence of a two-dimensional, dark-coloured body outline, often considered to be ‘organic’ or ‘carbonaceous’ in composition, and the extent of skeletal completeness and articulation. This disguises both the complexity of the biostratinomic and diagenetic processes that were involved and the level of anatomical detail than can be preserved, most notably the fossilisation of micron-sized melanosomes and the replication of labile tissues in calcium phosphate.

Analysis of skeletal disarticulation patterns will involve establishing and interrogating a dataset erected after visual inspection and imaging of fossils. Lithological context and details of soft tissue preservation will be established by sampling fossiliferous slabs for SEM stub samples, uncovered polished thin sections and polished blocks; these will be studied using petrological microscopes, SEM-EDX, X-ray mapping and EPMA. These results will be integrated into facies models erected using the field-based investigations of the sedimentology of key localities.

The project requires a student with a thorough grounding in field and laboratory aspects of sedimentology, and with some experience in interpreting taphonomic contexts. The student must be self-reliant and self-motivated in order to maximise the opportunities of working in China. Field work will be accompanied by others from the UK team, and by a Chinese national. The project provides the PGRA with broad training in sedimentology, analytical methods, taphonomy and geochemistry, all core skills for employment in a range of academic (earth and environmental sciences) and industrial (oil industry) settings.

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Last updated: 5/12/11