Paired Calcium and Clumped Isotopes, Tools to Probe Changing Diagenetic Systems

Explore paired calcium and clumped isotopes as tools for investigating changing diagenetic systems in this one-hour conference talk. Delve into the study of an evolving carbonate margin on the present-day western Bahamian slope, examining how these isotopes are affected differently by carbonate recrystallization. Learn about quantifying recrystallization rates and fluid flow into the margin, and discover how the onset of drift deposits in the Straits of Florida significantly increased fluid flow. Gain insights into the importance of larger platform structures in governing diagenetic reactions. Examine the depositional setting of the Bahamian Margin, fluid-carbonate reactive exchange, and its effects on geochemical records. Investigate the complexities of shallow carbonate as a chemical archive and the challenges of interpreting conflicting geochemical signals. Understand methods for constraining reaction and recrystallization rates, including clumped isotope analysis and modeling variable reaction rates. Explore datasets for calcium-84 on the Bahamian margin and learn how to solve for advection rates. Discover techniques for correcting carbon-13 records for diagenesis and interpreting carbon isotopes on the platform margin. Gain a comprehensive understanding of carbonate and fluid geochemistry modeling over time, considering both reactive and advective behaviors in diagenetic systems.

Intro
Talk layout: • Depositional setting: The Bahamian Margin Fluid-carbonate reactive exchange and its effects on geochemical records
Depositional Setting: Bahamian Margin • Platform margin sediment consists of re-deposited shallow marine sediments and pelagic material
Depositional Setting: Site 1003 ODP Site 1003 - Sampled on ODP Leg 166 in 1997
Shallow carbonate as a chemical archive? . Complicated - margin carbonate archives give conflicting, often contradictory geochemical signals to less complicated pelagic archives.
Fluid-sediment reactive exchange
The problem • Because sediments are progressively buried over time, recrystallizing sediments exchange with porefluids with different degrees of rock-buffering.
How to constrain reaction rate
Clumped isotopes: a one-slide primer
How to constrain recrystallization rate
Modeling variable reaction rate A single function for early and late diagenesis
How fast do fluids flow into margin?
A dataset for 84Ca on the Bahamian margin
Solving for advection rate
Fluid flow rates into the Bahamian margin
Correcting a 813C record for diagenesis
What can we do with these advection rates?
Carbon Isotopes on the platform margin
A consistent story?
Dissecting The problem • Diffusion rates are well-constrained experimentally
Summarizing the process . Carbonate and fluid geochemistry can be modeled over time. . This requires an understanding of reactive and advective behavior
Thank you for listening Referencing of work
IAS