Abstrakt
Spherical objects, identified as microfossils and named Isuasphaera isua (Pflug), were reported in 1978 from a chert in the 3.7-3.8 Ga Isua Greenstone Belt (IGB). Soon afterwards the biological nature of these objects was questioned on a number of grounds by several authors.
Following renewed, recent claims for biogenicity, the locality has been revisited and the host-rock (metamorphosed chert) to the putative microfossils re-examined. Extreme stretching deformation of the metachert cannot possibly have preserved syn-depositional spherical objects. We conclude that the objects (whether biological or not) are entirely post-tectonic and probably result from pre-Quaternary weathering.
Originalsprog | Engelsk |
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Sider (fra-til) | 309-312 |
Antal sider | 4 |
Tidsskrift | Precambrian Research |
Vol/bind | 126 |
Udgave nummer | 3-4 |
DOI | |
Status | Udgivet - 10 okt. 2003 |
Programområde
- Programområde 4: Mineralske råstoffer