JOURNEY THROUGH TIME WITHOUT OXYGEN or HOW FAR IT CAN BE TO GET DEEP KNOWLEDGE

             

As everybody knows, oxygen is an essential gas both for plants and human or animals to live. “Is it so important to know?” – maybe someone asks. Really, YES, because if without food human can live about 1 month, without water up to 1 week but without oxygen just 5 minutes. So, our dependence on oxygen makes to think about its distribution in air and causes of its appearance in an atmosphere. “Is it important to know why oxygen appears?” – maybe asks other body. Apparently, yes, because knowing reasons of oxygen inception we can predict its future and naturally fortune of mankind. 

As history of Earth numbers 4,6 billions years scientists need to travel through time using records (sedimentary and volcanic rocks) remained from deep time to understand processes occurred on the Earth’s surface. For this purpose in summertime 2007 a group of people set off for a time travel called FAR-DEEP (The Fennoscandia Arctic Russia - Drilling Early Earth Project) in Arctic Russia as place where records are well-preserved. This journey was conceived by Professor Victor A. Melezhik from Geological Survey of Norway, Trondheim and University of Bergen. The main idea was to understand processes and events which occurred during the Archean- Palaeoproterozoic (AR-PR) transition period (2,500-2,000 million years ago (Ma)) when as believed the oxygen level was dramatically increased. On the Figure 1 you can see places of drilling where volcanic-sedimentary consequences are presented. This is Murmansk region and Karelia located on the Fennoscandian shield where summer is mostly like winter in Washington, DC. Latitudes of these regions equal to latitudes of Alaska in the USA and geologists needed to not only survive but work very hard to get core material (Figure 2).

Well, FAR-DEEP fieldwork started and finished in 2007, where I also took part for 2.5 months to carry out the documentation of the core. There was a great experience of fieldwork and a collective collaboration. During the fieldwork stage our group faced many difficulties needed to be overcome. We worked 7/24 in our field camp (Figure 3) to receive the core material and if your turn was to work at night be prepared to fight with unsparing wind and perishing cold.

  Even change the place was a big trouble because of absent of a road and slash. Eventually 15 holes were drilled to get 3650 meters core what sounds like a distance between the Lincoln Memorial and the US Capitol in DC but reflects 500 million years as 1/9 part of the all Earth’s history. After summer 2007 the core was brought to Trondheim for further sampling among collaborators and multidisciplinary studying.

During those 500 millions years many events and changes occurred in and on the Earth. Among them are:

1.           Global rifting (simply said huge cracks in the ground with the size of more then New York state) with the worldwide spread LIP (Large Igneous provinces) related with the richest deposits of copper, nickel, chromium, platinum etc.

2.       The GOE (Great Oxidation Event) when oxygen changed from almost 0% to 1% of present atmospheric level (now the oxygen concentration is 21%) that means that oxygen is presented in the atmosphere just for half of its history. And question is: “What trigger was to make oxygen to appear?”

3.             Signatures of the first petroleum generation (so-called Shunga Event). Petroleum which we use for human needs (e.g. plastic, gasoline, clothes and even cosmetics) and which price is a crucial factor in current economy as large deposits appeared about 600 million years ago but scientists found its trace 2,000 million years ago.

            Picture 4 represents other global events which like a mystery occurred at the same time near AR-PR boundary. Scientists want to understand which one was a cause and which one was a consequence.   

Figure 4. δ¹³C - time plot with main events happened at Palaeproterozoic time

          The collaborators involved in the project are from many countries (Russia, the USA, Norway, Germany, Scotland etc.) and they are doing research ranging from palaebiology to geochronology. Currently, the core samples are analyzing and comparing with similar succession from Gabon.

           Here are some links and references about this challenging Project:
Official page of the FAR-DEEP

One of the recent posts with nice pictures

Melezhik, V.A., Fallick, A.E., Hanski, E.J., Kump, L.R., Lepland, A., Prave, A.R., and Strauss, H., 2005. Emergence of the aerobic biosphere during the Archean-Proterozoic transition: Challenges of future research. Geol. Soc. Am. Today, 15:4–11. full text of the paper