Stalker Jovian
Number of posts : 540 Age : 33 Location : Paris, France Registration date : 2008-06-16
| Subject: Did Curiosity discovered evidences of fossil life on Mars? 12th January 2015, 2:35 pm | |
| Strange but this news wasnt on every news paper around the world. Yeah, I know, another "evidence of fossil life on Mars" but this paper seems to be very serious and the autor is carefull. Nora Noffke found on Curiosity's images something reminding her of what she was working on for years: microbially-induced sedimentary structures or MISS. - Chris McKay wrote:
- I’ve seen many papers that say ‘Look, here’s a pile of dirt on Mars, and here’s a pile of dirt on Earth. And because they look the same, the same mechanism must have made each pile on the two planets.
[...] That’s an easy argument to make, and it’s typically not very convincing. However, Noffke’s paper is the most carefully done analysis of the sort that I’ve seen, which is why it’s the first of its kind published in Astrobiology. The paper: http://online.liebertpub.com/doi/pdf/10.1089/ast.2014.1218]Ancient Sedimentary Structures in the < 3.7 Ga Gillespie Lake Member, Mars, That Resemble Macroscopic Morphology, Spatial Associations, and Temporal Succession in Terrestrial Microbialites - Nora Noffke wrote:
- Sandstone beds of the < 3.7 Ga Gillespie Lake Member on Mars have been interpreted as evidence of an ancient
playa lake environment. On Earth, such environments have been sites of colonization by microbial mats from the early Archean to the present time. Terrestrial microbial mats in playa lake environments form microbialites known as microbially induced sedimentary structures (MISS). On Mars, three lithofacies of the Gillespie Lake Member sandstone display centimeter- to meter-scale structures similar in macroscopic morphology to terrestrial MISS that include ‘‘erosional remnants and pockets,’’ ‘‘mat chips,’’ ‘‘roll-ups,’’ ‘‘desiccation cracks,’’ and ‘‘gas domes.’’ The microbially induced sedimentary-like structures identified in Curiosity rover mission images do not have a random distribution. Rather, they were found to be arranged in spatial associations and temporal successions that indicate they changed over time. On Earth, if such MISS occurred with this type of spatial association and temporal succession, they would be interpreted as having recorded the growth of a microbially dominated ecosystem that thrived in pools that later dried completely: erosional pockets, mat chips, and roll-ups resulted from water eroding an ancient microbial mat–covered sedimentary surface; during the course of subsequent water recess, channels would have cut deep into the microbial mats, leaving erosional remnants behind; desiccation cracks and gas domes would have occurred during a final period of subaerial exposure of the microbial mats. In this paper, the similarities of the macroscopic morphologies, spatial associations, and temporal succession of sedimentary structures on Mars to MISS preserved on Earth has led to the following hypothesis: The sedimentary structures in the < 3.7 Ga Gillespie Lake Member on Mars are ancient MISS produced by interactions between microbial mats and their environment. Proposed here is a strategy for detecting, identifying, confirming, and differentiating possible MISS during current and future Mars missions. Press release_________________ | |
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