SGER: Massive Sediment Remobilization Off the Mississippi Delta in Response to Hurricane Ivan

点击翻译按钮获取中文摘要

ABSTRACTOCE-0500971In this project, a researcher at East Carolina University and his students will study the impact of Hurricane Ivan (September 2004) on sediment remobilization and redeposition near the Mississippi Delta. 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. Earlier studies by the principal investigator and others have inferred from geochemical and meteorological data that sediments are remobilized and exported cross/off shelf during the winter months in association with increased storm activity. With funding through this Small Grant for Exploratory Research, the principal investigator will extend an ongoing 12-month 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, he expects to make an estimate of sediment export and deposition associated with a single storm. He hypothesizes 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.Broader Impacts: This research 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. The research should 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. The principle investigator will use a 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.