US EPA

613995 

Journal Article 

Three-dimensional Magnetic Resonance Imaging of fossils across taxa 

Mietchen, D; Aberhan, M; Manz, B; Hampe, O; Mohr, B; Neumann, C; Volke, F 

2008 

Yes 

Biogeosciences
ISSN: 1726-4170
EISSN: 1726-4189 

5 

1 

25-41 

The frequency of life forms in the fossil record is largely determined by the extent to which they were mineralised at the time of their death. In addition to mineral structures, many fossils nonetheless contain detectable amounts of residual water or organic molecules, the analysis of which has become an integral part of current palaeontological research. The methods available for this sort of investigations, though, typically require dissolution or ionisation of the fossil sample or parts thereof, which is an issue with rare taxa and outstanding materials like pathological or type specimens. In such cases, non-destructive techniques could provide a valuable methodological alternative. While Computed Tomography has long been used to study palaeontological specimens, a number of complementary approaches have recently gained ground. These include Magnetic Resonance Imaging (MRI) which had previously been employed to obtain three-dimensional images of pathological belemnites non-invasively on the basis of intrinsic contrast. The present study was undertaken to investigate whether ¹H MRI can likewise provide anatomical information about non-pathological belemnites and specimens of other fossil taxa. To this end, three-dimensional MR image series were acquired from intact non-pathological invertebrate, vertebrate and plant fossils. At routine voxel resolutions in the range of several dozens to some hundreds of micrometers, these images reveal a host of anatomical details and thus highlight the potential of MR techniques to effectively complement existing methodological approaches for palaeontological investigations in a wide range of taxa. As for the origin of the MR signal, relaxation and diffusion measurements as well as ¹H and ¹³C MR spectra acquired from a belemnite suggest intracrystalline water or hydroxyl groups, rather than organic residues. ABSTRACT FROM AUTHOR Copyright of Biogeosciences is the property of European Geosciences Union and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts) 

FOSSILS; BIOLOGY -- Classification; THREE-dimensional imaging; MAGNETIC resonance imaging; IMAGING systems; BIOMINERALIZATION; PALEONTOLOGY; THICKNESS measurement; MICROMETER