what is life the emergence of life in a mineral world

The premise of this talk is that, apart from liquid water and carbon molecules, specific environmental components and conditions were essential for the origin of life, i.e. phosphate, reactive rock..

The CaliPhoto Method

International audienceWe propose an innovative method based on photography and image processing of interdisciplinary relevance, permitting the uncomplicated and inexpensive evaluation of material properties. This method-CaliPhoto-consists of using a dedicated colour plate with a specific design, placed in the field of view of a photograph of the material to be characterized. A specific image processing workflow is then applied to obtain colour vectors independent of illumination conditions. The method works using commercial colour cameras (e.g., smartphone cameras), and the colour plate can be printed on any colour printer. Herein, we describe the principle of the method and demonstrate that it can be used to describe and compare samples, identify materials or make relatively precise concentration measurements. The CaliPhoto method is highly complementary to any scientific research and may find applications across a range of domains, from planetary science to oceanography. The method may also be widely used in industry

Nanoscale 3D quantitative imaging of 1.88 Ga Gunflint microfossils reveals novel insights into taphonomic and biogenic characters

International audiencePrecambrian cellular remains frequently have simple morphologies, micrometric dimensions and are poorly preserved, imposing severe analytical and interpretational challenges, especially for irrefutable attestations of biogenicity. The 1.88 Ga Gunflint biota is a Precambrian microfossil assemblage with different types and qualities of preservation across its numerous geological localities and provides important insights into the Proterozoic biosphere and taphonomic processes. Here we use synchrotron-based ptychographic X-ray computed tomography to investigate well-preserved carbonaceous microfossils from the Schreiber Beach locality as well as poorly-preserved, iron-replaced fossil filaments from the Mink Mountain locality, Gunflint Formation. 3D nanoscale imaging with contrast based on electron density allowed us to assess the morphology and carbonaceous composition of different specimens and identify the minerals associated with their preservation based on retrieved mass densities. In the Mink Mountain filaments, the identification of mature kerogen and maghemite rather than the ubiquitously described hematite indicates an influence from biogenic organics on the local maturation of iron oxides through diagenesis. This non-destructive 3D approach to microfossil composition at the nanoscale within their geological context represents a powerful approach to assess the taphonomy and biogenicity of challenging or poorly preserved traces of early microbial life, and may be applied effectively to extraterrestrial samples returned from upcoming space missions

Aqueous alteration processes in Jezero crater, Mars—implications for organic geochemistry

The Perseverance rover landed in Jezero crater, Mars, in February 2021. We used the Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) instrument to perform deep-ultraviolet Raman and fluorescence spectroscopy of three rocks within the crater. We identify evidence for two distinct ancient aqueous environments at different times. Reactions with liquid water formed carbonates in an olivine-rich igneous rock. A sulfate-perchlorate mixture is present in the rocks, which probably formed by later modifications of the rocks by brine. Fluorescence signatures consistent with aromatic organic compounds occur throughout these rocks and are preserved in minerals related to both aqueous environments

Couplage de l'instrumentation et de la méthodologie dans la recherche de traces de vie sur les primitives Terre et Mars

Evaluating the nature of the earliest, often controversial, traces of life in the geological record (dating to the Palaeoarchaean, up to ~3.5 billion years before the present) is of fundamental relevance for placing constraints on the potential that life emerged on Mars at approximately the same time (the Noachian period). In their earliest histories, the two planets shared many palaeoenvironmental similarities, before the surface of Mars rapidly became inhospitable to life as we know it. Multi-scalar, multi-modal analyses of fossiliferous rocks from the Barberton greenstone belt of South Africa and the East Pilbara terrane of Western Australia are a window onto primitive prokaryotic ecoystems. Complementary petrographic, morphological, (bio)geochemical and nanostructural analyses of chert horizons and the carbonaceous material within using a wide range of techniques – including optical microscopy, SEM-EDS, Raman spectroscopy, PIXE, µCT, laser ablation ICP-MS, high-resolution TEM-based analytical techniques and secondary ion mass spectrometry – can characterise, at scales from macroscopic to nanoscopic, the fossilised biomes of the earliest Earth. These approaches enable the definition of the palaeoenvironments, and potentially metabolic networks, preserved in ancient rocks. Modifying these protocols is necessary for Martian exploration using rovers, since the range and power of space instrumentation is significantly reduced relative to terrestrial laboratories. Understanding the crucial observations possible using highly complementary rover-based payloads is therefore critical in scientific protocols aiming to detect traces of life on Mars.L'évaluation de la nature des traces de vie les plus anciennes, souvent controversées, dans les archives géologiques (datant du Paléoarchéen, jusqu'à environ 3,5 milliards d'années avant nos jours) est d'une importance fondamentale pour imposer des contraintes sur le potentiel d'émergence de la vie sur Mars à environ la même époque (Noachien). Au cours de leurs premières histoires, les deux planètes partageaient de nombreuses similitudes paléoenvironnementales, avant que la surface de Mars ne devienne rapidement inhospitalière à la vie telle que nous la connaissons. Les analyses multiscalaires et multimodales des roches fossilifères de la ceinture de roches vertes de Barberton en Afrique du Sud et du terrain d'East Pilbara en Australie occidentale sont une fenêtre sur les écosystèmes procaryotes primitifs. Analyses complémentaires pétrographiques, morphologiques, (bio)géochimiques et nanostructurales des horizons de Chert et des matériaux carbonés qu'ils contiennent à l'aide d'un large éventail de techniques - notamment la microscopie optique, SEM-EDS, spectroscopie Raman, PIXE, µCT, ablation laser ICP-MS, techniques analytiques basées sur la haute résolution TEM et la spectrométrie de masse des ions secondaires – peuvent caractériser, à des échelles allant du macroscopique au nanoscopique, les biomes fossilisés de la Terre primitive. Ces approches permettent de définir les paléoenvironnements, et potentiellement les réseaux métaboliques, préservés dans les roches anciennes. La modification de ces protocoles est nécessaire pour l'exploration martienne à l'aide de rovers, car la portée et la puissance des instruments spatiaux sont considérablement réduites par rapport aux laboratoires terrestres. Comprendre les observations cruciales possibles à l’aide de charges utiles hautement complémentaires basées sur des rovers est donc essentiel dans les protocoles scientifiques visant à détecter des traces de vie sur Mars

Impacts of Biological and Abiotic Networks. Discussion Leader Introductory Presentation

International audienc

Couplage de l'instrumentation et de la méthodologie dans la recherche de traces de vie sur les primitives Terre et Mars

Evaluating the nature of the earliest, often controversial, traces of life in the geological record (dating to the Palaeoarchaean, up to ~3.5 billion years before the present) is of fundamental relevance for placing constraints on the potential that life emerged on Mars at approximately the same time (the Noachian period). In their earliest histories, the two planets shared many palaeoenvironmental similarities, before the surface of Mars rapidly became inhospitable to life as we know it. Multi-scalar, multi-modal analyses of fossiliferous rocks from the Barberton greenstone belt of South Africa and the East Pilbara terrane of Western Australia are a window onto primitive prokaryotic ecoystems. Complementary petrographic, morphological, (bio)geochemical and nanostructural analyses of chert horizons and the carbonaceous material within using a wide range of techniques – including optical microscopy, SEM-EDS, Raman spectroscopy, PIXE, µCT, laser ablation ICP-MS, high-resolution TEM-based analytical techniques and secondary ion mass spectrometry – can characterise, at scales from macroscopic to nanoscopic, the fossilised biomes of the earliest Earth. These approaches enable the definition of the palaeoenvironments, and potentially metabolic networks, preserved in ancient rocks. Modifying these protocols is necessary for Martian exploration using rovers, since the range and power of space instrumentation is significantly reduced relative to terrestrial laboratories. Understanding the crucial observations possible using highly complementary rover-based payloads is therefore critical in scientific protocols aiming to detect traces of life on Mars.L'évaluation de la nature des traces de vie les plus anciennes, souvent controversées, dans les archives géologiques (datant du Paléoarchéen, jusqu'à environ 3,5 milliards d'années avant nos jours) est d'une importance fondamentale pour imposer des contraintes sur le potentiel d'émergence de la vie sur Mars à environ la même époque (Noachien). Au cours de leurs premières histoires, les deux planètes partageaient de nombreuses similitudes paléoenvironnementales, avant que la surface de Mars ne devienne rapidement inhospitalière à la vie telle que nous la connaissons. Les analyses multiscalaires et multimodales des roches fossilifères de la ceinture de roches vertes de Barberton en Afrique du Sud et du terrain d'East Pilbara en Australie occidentale sont une fenêtre sur les écosystèmes procaryotes primitifs. Analyses complémentaires pétrographiques, morphologiques, (bio)géochimiques et nanostructurales des horizons de Chert et des matériaux carbonés qu'ils contiennent à l'aide d'un large éventail de techniques - notamment la microscopie optique, SEM-EDS, spectroscopie Raman, PIXE, µCT, ablation laser ICP-MS, techniques analytiques basées sur la haute résolution TEM et la spectrométrie de masse des ions secondaires – peuvent caractériser, à des échelles allant du macroscopique au nanoscopique, les biomes fossilisés de la Terre primitive. Ces approches permettent de définir les paléoenvironnements, et potentiellement les réseaux métaboliques, préservés dans les roches anciennes. La modification de ces protocoles est nécessaire pour l'exploration martienne à l'aide de rovers, car la portée et la puissance des instruments spatiaux sont considérablement réduites par rapport aux laboratoires terrestres. Comprendre les observations cruciales possibles à l’aide de charges utiles hautement complémentaires basées sur des rovers est donc essentiel dans les protocoles scientifiques visant à détecter des traces de vie sur Mars

Couplage de l'instrumentation et de la méthodologie dans la recherche de traces de vie sur les primitives Terre et Mars

L'évaluation de la nature des traces de vie les plus anciennes, souvent controversées, dans les archives géologiques (datant du Paléoarchéen, jusqu'à environ 3,5 milliards d'années avant nos jours) est d'une importance fondamentale pour imposer des contraintes sur le potentiel d'émergence de la vie sur Mars à environ la même époque (Noachien). Au cours de leurs premières histoires, les deux planètes partageaient de nombreuses similitudes paléoenvironnementales, avant que la surface de Mars ne devienne rapidement inhospitalière à la vie telle que nous la connaissons. Les analyses multiscalaires et multimodales des roches fossilifères de la ceinture de roches vertes de Barberton en Afrique du Sud et du terrain d'East Pilbara en Australie occidentale sont une fenêtre sur les écosystèmes procaryotes primitifs. Analyses complémentaires pétrographiques, morphologiques, (bio)géochimiques et nanostructurales des horizons de Chert et des matériaux carbonés qu'ils contiennent à l'aide d'un large éventail de techniques - notamment la microscopie optique, SEM-EDS, spectroscopie Raman, PIXE, µCT, ablation laser ICP-MS, techniques analytiques basées sur la haute résolution TEM et la spectrométrie de masse des ions secondaires – peuvent caractériser, à des échelles allant du macroscopique au nanoscopique, les biomes fossilisés de la Terre primitive. Ces approches permettent de définir les paléoenvironnements, et potentiellement les réseaux métaboliques, préservés dans les roches anciennes. La modification de ces protocoles est nécessaire pour l'exploration martienne à l'aide de rovers, car la portée et la puissance des instruments spatiaux sont considérablement réduites par rapport aux laboratoires terrestres. Comprendre les observations cruciales possibles à l’aide de charges utiles hautement complémentaires basées sur des rovers est donc essentiel dans les protocoles scientifiques visant à détecter des traces de vie sur Mars.Evaluating the nature of the earliest, often controversial, traces of life in the geological record (dating to the Palaeoarchaean, up to ~3.5 billion years before the present) is of fundamental relevance for placing constraints on the potential that life emerged on Mars at approximately the same time (the Noachian period). In their earliest histories, the two planets shared many palaeoenvironmental similarities, before the surface of Mars rapidly became inhospitable to life as we know it. Multi-scalar, multi-modal analyses of fossiliferous rocks from the Barberton greenstone belt of South Africa and the East Pilbara terrane of Western Australia are a window onto primitive prokaryotic ecoystems. Complementary petrographic, morphological, (bio)geochemical and nanostructural analyses of chert horizons and the carbonaceous material within using a wide range of techniques – including optical microscopy, SEM-EDS, Raman spectroscopy, PIXE, µCT, laser ablation ICP-MS, high-resolution TEM-based analytical techniques and secondary ion mass spectrometry – can characterise, at scales from macroscopic to nanoscopic, the fossilised biomes of the earliest Earth. These approaches enable the definition of the palaeoenvironments, and potentially metabolic networks, preserved in ancient rocks. Modifying these protocols is necessary for Martian exploration using rovers, since the range and power of space instrumentation is significantly reduced relative to terrestrial laboratories. Understanding the crucial observations possible using highly complementary rover-based payloads is therefore critical in scientific protocols aiming to detect traces of life on Mars

Coupling instrumentation and methodology in the search for traces of life on the early Earth and Mars

Evaluating the nature of the earliest, often controversial, traces of life in the geological record (dating to the Palaeoarchaean, up to ~3.5 billion years before the present) is of fundamental relevance for placing constraints on the potential that life emerged on Mars at approximately the same time (the Noachian period). In their earliest histories, the two planets shared many palaeoenvironmental similarities, before the surface of Mars rapidly became inhospitable to life as we know it. Multi-scalar, multi-modal analyses of fossiliferous rocks from the Barberton greenstone belt of South Africa and the East Pilbara terrane of Western Australia are a window onto primitive prokaryotic ecoystems. Complementary petrographic, morphological, (bio)geochemical and nanostructural analyses of chert horizons and the carbonaceous material within using a wide range of techniques – including optical microscopy, SEM-EDS, Raman spectroscopy, PIXE, µCT, laser ablation ICP-MS, high-resolution TEM-based analytical techniques and secondary ion mass spectrometry – can characterise, at scales from macroscopic to nanoscopic, the fossilised biomes of the earliest Earth. These approaches enable the definition of the palaeoenvironments, and potentially metabolic networks, preserved in ancient rocks. Modifying these protocols is necessary for Martian exploration using rovers, since the range and power of space instrumentation is significantly reduced relative to terrestrial laboratories. Understanding the crucial observations possible using highly complementary rover-based payloads is therefore critical in scientific protocols aiming to detect traces of life on Mars