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We present laboratory experiments on the growth of a tubular ice structure surrounding a plume of cold brine that descends under gravity into water with a higher freezing point. Brinicles are geological analogues of these structures found under sea ice in the polar regions on Earth. Brinicles are hypothesized to exist in the oceans of other celestial bodies, and being environments rich in minerals, serve a potentially analogous role as an ecosystem on icy-ocean worlds to that of submarine hydrothermal vents on Earth.

We present laboratory experiments on the growth of a tubular ice structure surrounding a plume of cold brine that descends under gravity into water with a higher freezing point. Brinicles are geological analogues of these structures found under sea ice in the polar regions on Earth. Brinicles are hypothesized to exist in the oceans of other celestial bodies, and being environments rich in minerals, serve a potentially analogous role as an ecosystem on icy-ocean worlds to that of submarine hydrothermal vents on Earth.

What have the Greeks ever done for us? Everything. This short commentary celebrating the earliest history of origin of life research seeks to bring to the attention of the community of origin of life researchers that there is a much longer tradition of scientific theories in this subject than some people are aware of; there are 2500 years of thinking that we should not forget about. In Ionian Greece, Thales initiated ideas that we can see as the beginnings of science itself. Anaximander, his pupil, was particularly interested in the origins of the world, including how life had arisen, and proposed a species of proto-evolutionary theory of the origin of life. 2500 years ago, Anaxagoras left Ionia for Athens taking ideas of scientific thinking with him. Anaxagoras is credited with being the originator of a further theory of the origin of life, that of panspermia. The scientific conception of knowledge was attacked almost immediately, and Anaxagoras ended up exiled, but that idea of the knowability of things survived and led, many centuries later, to the scientific revolution and to our current human civilization.

The supplementary material deposited in this dataset are movies at real time describing the crystal growth of ice brinicles in different experimental conditions simulating the natural forms found in Arctic and Antarctic oceans and other planets.

Filaments in a planar chemical garden grow following tortuous, erratic paths. We show from statistical mechanics that this scaling results from a self-organized dispersion mechanism. Effective diffusivities as high as 10−5 m2 s−1 are measured in 2D laboratory experiments. This efficient transport is four orders of magnitude larger than molecular diffusion in a liquid, and ensures widespread contact and exchange between fluids in the chemical-garden structure and its surrounding environment.

Methane-rich water moves through conduits beneath the seafloor whose surfaces are formed through precipitation reactions. To understand how such submarine fluid conduit and venting systems form and grow, we develop a detailed mathematical model for this reaction-advection system and we quantify the evolution of an ensemble of similar filaments. We show that this growth can be described by a superposition of advection and dispersion. We analyze analog laboratory experiments of chemical-garden type to study the growth of a single filament undergoing a precipitation reaction with the surrounding environment. We apply these findings to geological fluid conduit and venting systems, showing that their irregular trajectories can lead to very effective spreading within the surrounding seabed, thus enhancing contact and exchanges of chemicals between the conduit and external fluids. We discuss how this methane venting leads to the formation of marine authigenic carbonate rocks, and for confirmation, we analyze two field samples from the Gulf of Cadiz for composition and mineralogy of the precipitates. We note the implications of this work for hydrate melting and methane escape from the seabed.