A new microbial ecosystem existed in bubbles of 400 million year old volcanic rocks and may well be found in three billion year old rocks: That is the gist of an article by Prof. Jörn Peckmann of the MARUM - Center for Marine Environmental Sciences at the University of Bremen. The article will be published in the march issue of the journal Geobiology.
Peckmann and his team found mineral deposits in former cavities of pillow basalts that are best explained by the theory that microbes lived deep within the rocks. Their fossils were found in rocks formed from lava that flowed out of the sea floor. Now they are part of the Rheinische Schiefergebirge, about 50 kilometers west of the German town of Kassel.
"Microbes are hardy creatures, they thrive where nobody would even look for life", says geologist Jörn Peckmann, professor at the MARUM - Center for Marine Environmental Sciences at the University of Bremen. "One of these places is in the middle of a rock." Because the microbes lived inside the rock, their fossils are well protected against the ravages of time. "And since they present a possibly very ancient ecosystem, it might be possible to find specimen considerably older than three billion years", hopes Jörn Peckmann.
But how do microbes get inside the rock? When lava flows out of an underwater volcano it is cooled quickly and forms typical shapes, so called pillow basalt. "This lava often contains large amounts of gas, so that the resultant rocks are full of bubbles", explains the geologist. "Through fine pores and cracks sea water circulates in the bubbles of diameters of usually less than a few millimeters." The water transports dissolved minerals, which get deposited on the walls. On these deposits grow microbes, which also travelled with the pore water. With age this porosity lessens because all the bubbles, pores and cracks are filled by the minerals transported by the pore water.
The thin sections of rocks analysed by the team clearly show thin regular strands of three to eight microns wide, encrusted by mineral deposits. Living microbes today show similar deposits. A clear indication that the structures found in the basaltic rocks were indeed formed by living organisms. Further evidence comes from the size and form of the structures which is consistent with microbial activity. The fact that the structures in question occur inside the bubbles of the intact rock also strengthens Peckmanns theory. Would the structures occur along fracture planes or crystal borders they could be explained by physical processes that often occur there.
"The most astonishing thing is, that we found these inclusions not only in the Rheinische Schiefergebirge in Hesse, but also in similarly aged pillow basalts in Thuringia and Bavaria. It seems as if these organisms were quite common", stresses the geologist from Bremen. What the microbes did in the rocks and what nourished them is still a riddle for the MARUM-team. Iron is one of the possible energy sources discussed. "Our further steps are to investigate whether this form of life was common and whether it still exists today." A question that is not irrelevant. "We think these organisms were quite common. If that is the case, they might have had a great influence on the chemistry of the basaltic rocks at the sea floor and therefore on sea water chemistry." And this in turn would have influenced the conditions for other organisms. "This would mean that we have to rewrite some explanations of how and why life in the oceans changed."
Further information, interviews, images:Kirsten Achenbach
Kirsten Achenbach | idw
GPM sees deadly tornadic storms moving through US Southeast
01.12.2016 | NASA/Goddard Space Flight Center
Cyclic change within magma reservoirs significantly affects the explosivity of volcanic eruptions
30.11.2016 | Johannes Gutenberg-Universität Mainz
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy