In order to determine when oxygen levels increased in the earth atmosphere, which element did james farquhar and his team search for in rocks

sulfur

James Farquhar is a professor in the Department of Geology and the Earth System Science Interdisciplinary Center (ESSIC) at the University of Maryland. The scientist is mainly known for the discovery of mass independent sulfur isotope signatures in samples from the Earth. This allowed him and his team to trace the evolution of oxygen and chemistry in the early atmosphere.

cavern

explanation:

for the crossword

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