Skip to content Skip to navigation

Article: Fossil diagenesis in the Burgess Shale

Publication: Palaeontology
Volume: 50
Part: 3
Publication Date: May 2007
Page(s): 537 543
Author(s): Nicholas J. Butterfield, Uwe Balthasar and Lucy A. Wilson
Addition Information

How to Cite

BUTTERFIELD, N. J., BALTHASAR, U., WILSON, L. A. 2007. Fossil diagenesis in the Burgess Shale. Palaeontology50, 3, 537–543.

Online Version Hosted By

Wiley Online Library
Get Article: Wiley Online Library [Pay-to-View Access] |

Abstract

Current models for the exceptional preservation of Burgess Shale fossils have focused on either the HF-extractable carbonaceous compressions or the mineral films identified by elemental mapping. BSEM, EDX and microprobe analysis of two-dimensionally preserved Marpolia, Wiwaxia and Burgessia identifies the presence of both carbonaceous and aluminosilicate films for most features, irrespective of original lability. In the light of the deep burial and greenschist facies metamorphism documented for the Burgess Shale, the aluminosilicate films are identified as products of late-stage volatilization and coincident mineralization of pre-existing compression fossils, whereas the three-dimensionally preserved gut-caecal system of Burgessia is interpreted as an aluminosilicate replacement of a pre-existing carbonate phase. The case for late diagenetic emplacement of aluminosilicate minerals is supported by the extensive aluminosilicification of trilobite shell and (originally) calcareous veinlets in the Burgess Shale, as well as documentation of other secondarily aluminosilicified compression fossils. By distinguishing late diagenetic alteration from the early diagenetic processes responsible for exceptional preservation, it is possible to reconcile the range of preservational modes currently expressed in the Burgess Shale.
PalAss Go! URL: http://go.palass.org/57q | Twitter: Share on Twitter | Facebook: Share on Facebook | Google+: Share on Google+