@article {2774,
	title = {Testing the Utility of Geochemical Proxies to Reconstruct Holocene Coastal Environments and Relative Sea Level: A Case Study from Hungry Bay, Bermuda},
	journal = {Open Quaternary},
	volume = {5},
	year = {2019},
	month = {May-02-2019},
	abstract = {On low-lying, tropical and sub-tropical coastlines freshwater marshes may be replaced by salt-tolerant mangroves in response to relative sea-level rise. Pollen analysis of radiocarbon-dated sediment cores showed that such a change occurred in Hungry Bay, Bermuda during the late Holocene. This well-established paleoenvironmental trajectory provides an opportunity to explore if geochemical proxies (bulk-sediment δ13C and Rock-Eval pyrolysis) can reconstruct known environmental changes and relative sea level. We characterized surface sediment from depositional environments in Bermuda (freshwater wetlands, saline mangroves, and wrack composed of Sargassum natans macroalgae) using geochemical measurements and demonstrate that a multi-proxy approach can objectively distinguish among these environments. However, application of these techniques to the transgressive sediment succession beneath Hungry Bay suggests that freshwater peat and mangrove peat cannot be reliably distinguished in the sedimentary record, possibly because of post-depositional convergence of geochemical characteristics on decadal to multi-century timescales and/or the relatively small number of modern samples analyzed. Sediment that includes substantial contributions from Sargassum is readily identified by geochemistry, but has a limited spatial extent. Radiocarbon dating indicates that beginning at {\textendash}700 CE, episodic marine incursions into Hungry Bay (e.g., during storms) carried Sargassum that accumulated as wrack and thickened through repeated depositional events until ~300 CE. It took a further ~550 years for a peat-forming mangrove community to colonize Hungry Bay, which then accumulated sediment rapidly, but likely out of equilibrium with regional relative sea-level rise.},
	keywords = {mangrove, radiocarbon, Rock-Eval pyrolysis, Sargassum, δ13C},
	doi = {10.5334/oq.49},
	url = {http://www.openquaternary.com/articles/10.5334/oq.49/},
	author = {Kemp, Andrew C. and Vane, Christopher H. and Khan, Nicole S. and Ellison, Joanna C. and Engelhart, Simon E. and Horton, Benjamin P. and Nikitina, Daria and Smith, Struan R. and Rodrigues, Lisa J. and Moyer, Ryan P.}
}
@article {2815,
	title = {The distribution and utility of sea-level indicators in Eurasian sub-Arctic salt marshes (White Sea, Russia)},
	journal = {Boreas},
	volume = {46},
	year = {2017},
	month = {Jan-07-2017},
	pages = {562 - 584},
	abstract = {In support of efforts to reconstruct relative sea level (RSL), we investigated the utility of foraminifera, diatoms and bulk-sediment geochemistry (δ13C, C:N and parameters measured by Rock-Eval pyrolysis) as sea-level indicators in Eurasian sub-Arctic salt marshes. At three salt marshes (<15 km apart) in Dvina Bay (White Sea, Russia), we collected surface sediment samples along transects from subtidal to Taiga forest environments. Foraminifera at all sites formed bipartite assemblages, where elevations below mean high higher water (MHHW) were dominated by Miliammina spp. and elevations between MHHW and the highest occurrence of foraminifera were dominated by Jadammina macrescens and Balticammina pseudomacrescens. Five high-diversity groups of diatoms were identified and they displayed pronounced variability amongst the study sites. Bulk-sediment geochemistry recognized two groups (clastic-dominated environments below MHHW and organic-rich environments above MHHW). As one group included subtidal elevations and the other included supratidal elevations, we conclude that the measured geochemical parameters are not stand-alone sea-level indicators. Core JT2012 captured a regressive sediment succession of clastic, tidal-flat sediment overlain by salt-marsh organic silt and freshwater peat. The salt-marsh sediment accumulated at 2804{\textpm}52 years before present and preserved foraminifera (Jadammina macrescens and Balticammina pseudomacrescens) with good analogy to modern assemblages indicating that RSL was +2.60{\textpm}0.47 m at this time. Diatoms confirm that marine influence decreased through time, but the lack of analogy between modern and core assemblages limited their utility as sea-level indicators. Geochemical parameters also indicate a reduction in marine influence through time. We conclude that RSL reconstructions derived from salt-marsh sediment preserved beneath Eurasian sub-Arctic peatlands can provide valuable insight into the spatio-temporal evolution of the Fennoscandian and Eurasian ice sheets.},
	doi = {10.1111/bor.2017.46.issue-310.1111/bor.12233},
	url = {https://onlinelibrary.wiley.com/doi/10.1111/bor.12233},
	author = {Kemp, Andrew C. and Horton, Benjamin P. and Nikitina, Daria and Vane, Christopher H. and Potapova, Marina and Weber-Bruya, Elizabeth and Culver, Stephen J. and Repkina, Tatyana and Hill, David F.}
}
@article {2768,
	title = {Subduction zone slip variability during the last millennium, south-central Chile},
	journal = {Quaternary Science Reviews},
	volume = {175},
	year = {2017},
	month = {Jan-11-2017},
	pages = {112 - 137},
	abstract = {The Arauco Peninsula (37{\textdegree}-38{\textdegree}S) in south-central Chile has been proposed as a possible barrier to the along-strike propagation of megathrust ruptures, separating historical earthquakes to the south (1960 AD 1837, 1737, and 1575) and north (2010 AD, 1835, 1751, 1657, and 1570) of the peninsula. However, the 2010 (Mw 8.8) earthquake propagated into the Arauco Peninsula, re-rupturing part of the megathrust that had ruptured only 50 years earlier during the largest subduction zone earthquake in the instrumental record (Mw 9.5). To better understand long-term slip variability in the Arauco Peninsula region, we analyzed four coastal sedimentary sections from two sites (Tir{\'u}a, 38.3{\textdegree}S and Quidico, 38.1{\textdegree}S) located within the overlap of the 2010 and 1960 ruptures to reconstruct a \~{}600-year record of coseismic land-level change and tsunami inundation. Stratigraphic, lithologic, and diatom results show variable coseismic land-level change coincident with tsunami inundation of the Tir{\'u}a and Quidico marshes that is consistent with regional historical accounts of coseismic subsidence during earthquakes along the Valdivia portion of the subduction zone (1960 AD and 1575) and coseismic uplift during earthquakes along the Maule portion of the subduction zone (2010 AD, 1835, 1751). In addition, we document variable coseismic land-level change associated with three new prehistoric earthquakes and accompanying tsunamis in 1470{\textendash}1570 AD, 1425{\textendash}1455, and 270{\textendash}410. The mixed record of coseismic subsidence and uplift that we document illustrates the variability of down-dip and lateral slip distribution at the overlap of the 2010 and 1960 ruptures, showing that ruptures have repeatedly propagated into, but not through the Arauco Peninsula and suggesting the area has persisted as a long-term impediment to slip through at least seven of the last megathrust earthquakes (\~{}600 years).},
	keywords = {Coastal hazards, Coastal paleoseismology, Diatom paleoecology, Prehistoric earthquakes, Subduction zone segmentation, Tsunami Deposits},
	issn = {02773791},
	doi = {10.1016/j.quascirev.2017.08.023},
	url = {https://linkinghub.elsevier.com/retrieve/pii/S0277379117303505},
	author = {Dura, Tina and Horton, Benjamin P. and Cisternas, Marco and Ely, Lisa L. and Hong, Isabel and Nelson, Alan R. and Wesson, Robert L. and Pilarczyk, Jessica E. and Parnell, Andrew C. and Nikitina, Daria}
}
