Sprecher
Beschreibung
Life as we know it could most likely not have emerged in absence of active geological processes and the environments shaped by them. The quest of the most probable environment(s) is amongst the most challenging and heavily debated topics on the emergence of life. A key challenge remains however to identify environments favorable for a plethora of reactions allowing to progress from the synthesis of small molecules forming the simple building block of life, to complex organic molecules such as e.g. sugars or lipids and finally to functional polymers with the ability to metabolism and replication. Common to all promising geological environments are physical and /or chemical disequilibria driving change, in form of fluid-rock interaction such as e.g. leaching, precipitation and remineralization – all dynamically shaping their micro- and macro- environment. Fluid flow through a permeable (fracture) network enables efficient fluid-mediated transport and cycling of reactants and organic products, and is key to establish and/ or sustain chemical, temperature and pH gradients.
The scarcity of rock records for the early Archean Eon marks these periods as the least constrained ones in Earth’s history and fosters speculations about the earliest Earth geology and thus likely environments to explore on their feasibility for prebiotic chemical reactions. Geomaterials - glasses, minerals and rocks –exhibit different reactivity in contact with a fluid. The interesting highly reactive geomaterials, such as for instance glasses of mafic composition, however are not preserved in the rock records, with even their products likely to be altered and thus may be easily overlooked.
