The Early Palaeozoic Alum Shale Formation in northwestern Europe is rich in uranium up to several hundreds of ppm. Despite the absence of higher land plant precursors, the primary Type II kerogen in the Alum Shale has an abnormally strong aromatic character even at low thermal maturities, probably due to α-particle bombardment.

FT-ICR-MS data reveal that the macromolecules in the uranium-rich Alum Shale samples are less alkylated than less irradiated counterparts, and that oxygen containing-compounds are enriched in the uranium-rich samples but are not easily degradable into low-molecular-weight products due to irradiation-induced crosslinking.

Despite strong organic matter alteration, CO2 and CH4 are formed using U-rich samples in incubation experiments, and DNA-based high-throughput sequencing allows a detailed phylogenetic characterization of the indigenous microbial communities with implications of an uranium-adapted biosphere.

The alteration of macromolecular organic matter in the Alum Shale Formation is suggested as an Earth analogue of the Martian surface, in response to α-particle irradiation. Especially a comparison of potential habitats on the Martian surface with Kolm nodules of the Alum Shale in terms of irradiation dosage and organic geochemical characteristics reveals that they have received similar levels of irradiation.


Article metrics loading...

Loading full text...

Full text loading...



  1. Schulz, H.-M., Yang, S., Panova, E., Bechtel, A.
    (2019): The role of Pleistocene meltwater-controlled uranium leaching in assessing irradiation-induced alteration of organic matter and petroleum potential in the Tremadocian Koporie Formation (Western Russia). - Geochimica et Cosmochimica Acta, 245, 133–153.
    [Google Scholar]
  2. Yang, S., Schulz, H.-M., Horsfield, B., Schovsbo, N. H., Noah, M., Panova, E., Rothe, H., Hahne, K.
    (2018): On the changing petroleum generation properties of Alum Shale over geological time caused by uranium irradiation. - Geochimica et Cosmochimica Acta, 229, 20–35.
    [Google Scholar]
  3. Yang, S., Schulz, H.-M., Horsfield, B., Schovsbo, N. H., Grice, K., Zhang, J.
    (2020): Geological alteration of organic macromolecules by irradiation:Implication for organic matter occurrence on Mars. - Geology, 48, 7, 713–717.
    [Google Scholar]
  4. Yang, S., Schulz, H.-M., Schovsbo, N., Mayanna, S.
    (2019): The organic geochemistry of “Kolm”, a unique analogue for the understanding of molecular changes after significant uranium irradiation. - International Journal of Coal Geology, 209, 89–93.
    [Google Scholar]

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error