Fossil plants are commonly found preserved as impression/compression fossils; rarer but more informative are three-dimensional fossils, which can preserve the full or partial anatomy. Traditional palaeobotanical techniques for studying these 3D fossils – through physical sectioning to reveal surfaces for inspection – destroy some part of the fossil during preparation, resulting in data-loss. Tomography combined with ‘virtual palaeontology’ can overcome such limitations. This thesis documents the application of tomography to a number of different plant specimens, in various forms of preservation, with the aid of six case-studies. The first five case-studies demonstrate the use of tomographical methods to elucidate anatomical details of fossil plant organs; with each method improving data acquisition compared to the previous. The first details Physical Optical Tomography (POT) as a technique for extracting morphology from specimens where non-invasive x-rays are not amenable or historical physical dataset used. The second shows the advantages of non-destructive X-ray Micro-Tomography (XMT) in revealing the large scale structures of palaeobotanical material. The third investigates XMT combined with traditional destructive techniques to recover both the maximum morphology and cellular detail. The fourth uses XMT combined with Synchrotron Radiation X-ray Micro-Tomography (SRXMT), resulting in improvements to the visualisation of cellular anatomy. The fifth demonstrates that undescribed macro-sized palaeobotanical material may be fully taxonomically described through non-destructive SRXMT alone. The final case-study investigates the advantages and disadvantages of re-studying a pre-existing tomographic dataset and demonstrates that modern software and hardware enable enhanced data extraction. Discussion of the strengths and weaknesses of each method is undertaken, with details presented for the numerous experimental non-destructive XMT and SRXMT scans performed, informing which technique to use for a given fossil. Furthermore, differences in visualisation technique and problems associated with 3D modelling are discussed.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:718382 |
| Date | January 2015 |
| Creators | Spencer, Alan Richard Tozer |
| Contributors | Sutton, Mark D. |
| Publisher | Imperial College London |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/10044/1/46161 |
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