Saltmarsh Processes & Accretion

Overview

Saltmarshes counter the threat of accelerating sea-level rise, buffering coastal populations by reducing wave energy and flooding. Marshes respond to sea-level rise through a combination of upland migration and vertical accretion. Their ability to grow vertically apace with sea-level rise depends on the in-situ production of organic material and incorporation of allochthonous inorganic sediment. Current studies in our lab use sedimentologic (e.g., grain size, loss-on- ignition, foraminifera content), geochemical (biomarker compositions, bulk-sediment and biomarker stable isotopic compositions), and radioisotopic (Pb-210 & Cs-137 gamma spectroscopy) analyses.

The goals of these studies are to 1) explore the source of storm deposits across a range of backbarrier subenvironments, 2) determine the relative importance of nearshore, backbarrier, and fluvial reservoirs in providing sediment to saltmarshes during major storms, 3) quantify the processes, pathways, and mechanisms of sediment distribution to the marsh platform (e.g., storm-surge level and duration, wave exposure, local geomorphology, and river sediment discharge), and 4) evaluate the importance of storm and inlet sedimentation relative to long-term vertical marsh accretion.

Current projects explore these processes within barrier-associated saltmarshes of northern Florida, Georgia, South Carolina, Virginia, and Massachusetts. 

Publications

Please feel free to contact us for pdf copies of any of the following publications.  Note: * - Coastal Geology Lab student author

FitzGerald, D.M., Hein, C.J., *Connell, J.E., Hughes, Z.J., Georgiou, I.Y. and Novak, A.B., 2021. Largest marsh in New England near a precipice. Geomorphology, 379, p.107625. https://doi.org/10.1016/j.geomorph.2021.107625

Abstracts & Presentations

Links below will bring you to either full abstracts, or in the case of material associated with published work, online versions of ppt presentations or posters. Or, feel free to contact us for pdf copies of any of the following abstracts or their associated presentations or posters.  Note: * - student author

Connell, J.E., Hein, C.J., FitzGerald, D.M., Hughes, Z., Georgiou, I.Y., *King, K., 2021. The contribution of inorganic sediment inputs to multi-decadal accretion of backbarrier saltmarshes in the Southeast USA, American Geophysical Union Fall Meeting, New Orleans, LA, December 2021.

Connell, J.E., *Herbine, L.E., Gedan, K.B., Hughes, Z., FitzGerald, D.M., Georgiou, I.Y., Hein, C.J., 2019. Event-driven sedimentation in Massachusetts and Virginia salt marshes, Geological Society of America Southeast (SE-GSA) Section Meeting, Charleston, SC, March 2019.