SGER: Massive Sediment Remobilization Off The Mississippi Delta in Response to Hurricane Ivan Grant uri icon

abstract

  • Previous research conducted on the Mississippi Delta have inferred from geochemical and meteorological data that sediments are remobilized and exported cross/off shelf during the winter months, associated with increased storm activity. The crossing of Hurricane Ivan within 125 km of the delta offers a unique opportunity to evaluate the sediment disturbance and deposition/export associated with a major meteorological event. Over the last 12 months, we have collected an intense time series of cores on the shelf adjacent to the Mississippi delta in order to understand the short-term sediment dynamics. By responding rapidly to this act of nature, we will be able to provide an estimate of sediment deposition of export associated with a single storm. We hypothesize that massive sediment remobilization and export occurred during the crossing of hurricane Ivan, providing an "event layer" in the sediments that, when compared to cores and geophysical data collected during the last 12 months, should provide the first direct observation of sediment off-shelf transport proximal to the Mississippi delta. This proposal addresses fundamental issues of the role major storms play in the redistribution of sediments in coastal systems. The disturbance of the sea bed may enhance sediment reworking processes, and therefore have a direct influence on diagenetic reactions that occur in the sediments and on the composition of the buried material, as well as nutrient and oxygen availability in overlying waters. This research will help provide a better understanding of the dynamics and history of particles within river-dominated shelf environments. The timing, duration, and nature of this project offer an excellent opportunity to expose several (up to 6) upper level undergraduates to science at sea. Corbett will use this 3-day cruise as a field trip for the current sedimentology course being taught at ECU. Students will be exposed to sediment sampling methods and geophysical techniques and be able to apply many of the concepts from lectures throughout the semester.

date/time interval

  • April 2005 - March 2006