Gabon and Oxygenation of Earth – Drilling Early Earth Project (GOE-DEEP)

(c) Cross-bedded dolograinstone with pyrobitumen veins and pyrite crystals. (d) Example of thin resedimented volcaniclastic layers (e) Mn nodules (outlined in pale red shading). In outcrop, black shales weather to pale yellow-orange colours.

The first half of the Paleoproterozoic Era (e. 2500 - 2000 Ma) is arguably one of the most extraordinary intervals in Earth history. It includes the Great Oxidation Event (GOE) when Earth's surface environments and biosphere underwent a complete redox transformation to a planet rich in free dioxygen (02). The Francevillian succession (SE Gabon) is unique because it has undergone minimal deformation and experienced only minor thermal overprinting. Acquiring fresh core will form an underpinning framework to integrate sedimentological, stratigraphy, geochemical and geochronological datasets to gain knowledge on the processes that led to emergence of the modern aerobic Earth system. The project focuses on questions such as

*What was the nature in the evolutionary trend of the Proterozoic oxygen, carbon, sulphur, phosphorous and nitrogen cycles?

*What was the timing and tempo of the change in redox state of the ocean and atmosphere?

*What are the individual and composite basinal trends? How are events correlated globally?

*ls there independent evidence to assess the provocative idea that an exceptionally early metazoan biota evolved seemingly unique to the Franceville Basin?

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