How do we begin to understand what early life was like on Earth about 700 million years ago as our planet shifted from an oxygen-free and probably ice-covered realm to the oxygen-rich world that we know today?
One geochemist who decodes the early record of life on Earth has found a method featuring a combination of chemical analyses for a significantly clearer picture of this dynamic environment. Alison Olcott Marshall of the University of Kansas presented her findings today at the Goldschmidt Conference in Knoxville, Tenn. The conference is attended by several thousand geochemists and features new scientific discoveries regarding the Earth, energy and the environment. It is hosted by the University of Tennessee, Knoxville, and Oak Ridge National Laboratory.
Marshall is particularly interested in the time called Snowball Earth, a period at the end of the Precambrian Era when geochemists speculate that the world was covered from pole to pole with glacial ice and the existing organisms lived exclusively in water. At that time life was still primarily single-cell organisms. So Marshall looks at chemical fossils to recreate the environment. The chemical complexes left from the cell walls of these organisms are more abundant and more easily classified than body fossils within the samples.
Marshall's research carries her to southeast Brazil, where there is stable sedimentary rock from the late Precambrian era. Her samples come from exploratory drilling that reached eight hundred meters down into the core of black shale that was at the bottom of a sea 700 million years ago.
"The one caveat with biomarkers (chemical fossils) is that there is always a danger of contamination," Marshall said. Her initial tests using an instrument that looks at chemical compounds by molecular weight often had questionable results due to the possibility of contamination from material of a later period. However, by using another type of high resolution analysis called Raman spectroscopy, she also measured the subtle nuances of vibration that occur at the molecular level. Her high resolution results revealed two previously undetected distinctions in time generations.
The Goldschmidt Conference, held the week of June 13-19 in Knoxville, Tenn., is sponsored by a number of international geochemical societies and named for Victor Goldschmidt (1888-1947), the Swiss-Norwegian scientist and father of geochemistry.
Whitney Holmes | EurekAlert!
NASA's AIM observes early noctilucent ice clouds over Antarctica
05.12.2016 | NASA/Goddard Space Flight Center
GPM sees deadly tornadic storms moving through US Southeast
01.12.2016 | NASA/Goddard Space Flight Center
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
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...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
05.12.2016 | Power and Electrical Engineering
05.12.2016 | Materials Sciences
05.12.2016 | Power and Electrical Engineering