Publication Date:
2019
Description:
〈span〉Marine carbonate burial represents the largest long-term carbon sink at Earth’s surface,
occurring in both deep-sea (pelagic) environments and shallower waters along continental
margins. The distribution of carbonate accumulation has varied over geological history
and impacts the carbon cycle and ocean chemistry, but it remains difficult to quantitatively
constrain. Here, we reconstruct Cenozoic carbonate burial along continental margins using
a mass balance for global carbonate alkalinity, which integrates independent estimates
for continental weathering and pelagic carbonate burial. Our results indicate that major
changes in marginal carbonate burial were associated with important climate and sea-level
change events, including the Eocene-Oligocene transition (ca. 34 Ma), the Oligocene-Miocene
boundary Mi-1 glaciation (ca. 23 Ma), and the middle Miocene climate transition (ca. 14 Ma).
In addition, we find that a major increase in continental weathering from ca. 10 Ma to the
present may have driven a concomitant increase in pelagic carbonate burial. Together, our
results show that changes in global climate, sea level, and continental weathering have all
impacted carbonate burial over the Cenozoic, but the relative importance of these processes
may have varied through time.〈/span〉
Print ISSN:
0091-7613
Electronic ISSN:
1943-2682
Topics:
Geosciences
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