Encyclopedia of Astrobiology

Living Edition
| Editors: Muriel Gargaud, William M. Irvine, Ricardo Amils, Henderson James Cleaves, Daniele Pinti, José Cernicharo Quintanilla, Michel Viso

Concretions (Mars)

  • Alessandro Airo
Living reference work entry
DOI: https://doi.org/10.1007/978-3-642-27833-4_5024-2

Definition

Concretions are postdepositionally cemented areas within sedimentary rocks that occur as spheres, disks, tubes, botryoidal aggregates, or have an irregular lumpy shape. The cement forms through precipitation from pore water and is usually composed of carbonate (e.g., calcite, siderite), sulphate (e.g., gypsum), silica (e.g., chert), or iron oxide (e.g., hematite). Nodules have a similar origin, but instead of cementing the pre-existing sediment in place, they substitute the particles through relocation or dissolution.

The Mars Exploration Rover Opportunity was the first to discover concretions on Mars, the so-called ‘blueberries’, which are cemented by hematite (Squyres et al. 2004). The Mars Science Laboratory Curiosity has discovered light-toned concretions within mudstones at Gale crater, which possibly are cemented by sulphates (Grotzinger et al. 2014). The occurrence of concretions on Mars is insofar of interest to astrobiologists as they indicate the former presence...

Keywords

Iron Oxide Pore Water Bioorganic Chemistry Sedimentary Rock Science Laboratory 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
This is a preview of subscription content, log in to check access.

References

  1. Grotzinger JP et al (2014) A habitable fluvio-lacustrine environment at Yellowknife Bay, gale crater, mars. Science 343:386–387ADSCrossRefGoogle Scholar
  2. Squyres SW et al (2004) The opportunity Rover’s Athena science investigation at meridiani planum, mars. Science 306:1698–1703ADSCrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Institut für Geologische Wissenschaften Tektonik und Sedimentäre GeologieFreie Universität Berlin, Fachbereich GeowissenschaftenBerlinGermany