Deriving spatial and temporal patterns of coastal marsh aggradation from hurricane storm surge marker beds

摘要: Abstract This study uses storm surge sediment beds deposited by Hurricanes Audrey (1957), Carla (1961), Rita (2005) and Ike (2008) to investigate spatial temporal changes in marsh sedimentation on the McFaddin National Wildlife Refuge Southeastern Texas. Fourteen cores were collected along a transect extending 1230 m inland from Gulf coast. Storm-surge-deposited identified texture, organic content, carbonate presence of marine microfossils 137Cs dating. The hurricane-derived facilitate assessment nearshore locations over decadal annual timescales. Spatial variation reflects varying contributions three prevailing sources: flooding, overwash plants. Over about last decade, hurricane has been predominant source for because large inputs Ike. Farther inland, diminish is dominated deposition flood waters larger component. Temporal variations reflect activity, surface elevation degree compaction sediments, which time-dependent. There was little no period 2008–2014, firstly hurricanes impacted area secondly prior 2008 had increased elevations up 0.68 m, reducing subsequent flooding. Marsh rates relatively high 2005–2008, averaging 2.13 cm/year possibly reflecting Humberto Gustav. However, these sediments are highly largely uncompacted. Older, deeper deposits formed between 1961 2005 less organic-rich, more compacted have an average rate 0.38 cm/year, closely comparable long-term similar settings nearby. These results demonstrate utility using marker sedimentation, provide insights into sedimentary response coastal marshes useful guidance public policy aimed at combating effects sea-level rise northern Mexico.