For the deep biosphere, the present is not always the key to the past: what we can learn from the geological record.

Autor(en)

Patrick Meister

Abstrakt

Microbial life below the Earth's surface (the deep biosphere) has probably varied significantly since the Archaean. Reconstructing changes in deep biosphere activity over geological timescales is necessary to understand its role in biogeochemical cycling. Even for the last few million years, such changes are often not captured by studying the distribution of present activity. However, several studies using samples from scientific drilling have revealed mineralogical, geochemical, isotopic and fossil organic molecule imprints in the sedimentary record that document rather different past deep biosphere conditions. Changing deep biosphere conditions can also be simulated using geochemical models. While some processes occurring in the past can be understood by comparing them with the present deep biosphere, others lack any modern analogue - they are defined as non-actualistic. A non-actualistic consideration of the deep biosphere is therefore essential for a better understanding of how Earth and life co-evolved through time.

Organisation(en)

Institut für Geologie

Journal

Terra Nova: the European journal of geosciences

Band

27

Seiten

400-408

Anzahl der Seiten

9

ISSN

0954-4879

DOI

https://doi.org/10.1111/ter.12174

Publikationsdatum

2015

Peer-reviewed

Ja

ÖFOS 2012

105101 Allgemeine Geologie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/for-the-deep-biosphere-the-present-is-not-always-the-key-to-the-past-what-we-can-learn-from-the-geological-record(17b3ea59-1ef6-4f14-a687-a38ef3dfa298).html