NSF Award Abstract:
This project proposes to validate a new approach to measure porewater flow dynamics from deep sea sediments using a biologically conservative, naturally-occurring tracer, Radium 224, which is constantly produced by porewaters. The technique will be validated using independent measures of porewater fluxes (i.e. heat gradients and magnesium profiles) during a cruise to the Guaymas Basin in the Gulf of California that is already funded by NSF. Once validated the technique will be broadly applicable to all sedimentary environments including oceans, rivers/streams, wetlands and lakes. Understanding porewater flow dynamics is important to understanding ocean and other aquatic system chemical budgets, microbial ecology and global heat flow.
This proposal hypothesizes that the short-lived radium isotope Ra 224 may serve as an effective tracer of porewater flows in deep ocean systems, regardless of the type or composition of seepages, because its sources and sinks can be uniquely constrained. The method will be tested in the Guaymas Basin which is comprised of areas undergoing a range of seepage rates and offers porewater thermal gradients resulting from the hydrothermal system. As a result heat fluxes and gradients in magnesium and other cations affected by high-temperature water/rock interactions can be used to independently validate the porewater flows measured by Ra 224.
Dataset | Latest Version Date | Current State |
---|---|---|
Dissolved radium isotope activity around Guaymas Basin from samples collected by CTD and HOV Alvin during R/V Atlantis cruise AT42-05 in November 2018 | 2019-12-03 | Final no updates expected |
Dissolved radium isotope activity around Guaymas Basin from samples collected by CTD and HOV Alvin during R/V Atlantis cruise AT37-06 in December 2016 | 2019-11-26 | Final no updates expected |
Sedimentary radium isotope activity around Guaymas Basin from samples collected by HOV Alvin during R/V Atlantis cruise AT37-06 in December 2016 | 2019-11-25 | Final no updates expected |
Principal Investigator: Richard N. Peterson
Coastal Carolina University
Contact: Richard N. Peterson
Coastal Carolina University
DMP_Peterson_OCE-1558829.pdf (86.27 KB)
02/04/2019