Biogeochemical cycles of carbon and sulfur and their effect on atmospheric oxygen over phanerozoic time.pdf

Palaeogeography, Palaeoclimatology, Palaeoecology (Global and ary Change Section), 75 (1989) : 97-122 97
Elsevier Science Publishers ., Amsterdam - Printed in herlands
BIOGEOCHEMICAL CYCLES OF CARBON AND SULFUR
AND THEIR EFFECT ON ATMOSPHERIC OXYGEN
OVER PHANEROZOIC TIME
ROBERT A. BERNER
Yale University, Department o[ Geology and Geophysics, . Box 6666, New Haven, CT 06511 (.)
(Received October 18, 1987; accepted February 17, 1988)
Abstract
Berner, ., 1989. Biogeochemical cycles of carbon and sulfur and their effect on atmospheric oxygen over Phanerozoic
time. Palaeogeogr., Palaeoclimatol., Palaeeecol. (Global . Change Sect.), 75: 97-122.
The biogeochemical cycles of carbon and sulfur contain within them the principle processes that control the level of
atmospheric oxygen over Phanerozoic time. These are the production, deposition, burial and eventual oxidative
weathering anic matter and the ic formation, burial and eventual oxidative weathering of sedimentary
pyrite. Observations of modern sedimentary environments indicate that: (1) anic matter, on a worldwide basis, is
deposited in marine shelf-deltaic sediments, rather than in high-productivity upwelling regions or anoxic basins; (2) burial
rate and the degree of preservation anic matter are positively correlated with total sedimentation rate; (3) the rate
of position anic matter in natural waters and sediments is highly dependent on the source and degree of aging
of anic matter itself, and is largely unaffected by the concentration of the principal oxidants, 02 and SO2- ; (4)
pyrite sulfur concentration in normal marine environments correlates well anic carbon concentration due to the
limitation of bacterial sulfate reduction by anic matter that escapes aerobic destruction during deposition and
bioturbation; (5) depth-integrated sulfate reduction in normal marine sediments correlates positively with total sedimen-
tation rate; (6) in