GP Seminar - Jillian Maloney "Mass wasting on the Mississippi River delta front"


 
05/20/2016 - 3:30pm

Please join us for the GP Seminar

Friday, May 20, 3:30 pm
IGPP Conference Room (Munk 303)
(Coffee and snacks at 3:00 pm in the Reading Room!)
 
Mass wasting on the Mississippi River delta front
Jillian Maloney
Assistant Professor, SDSU

 

Sediment accumulation rates and patterns play an important role in governing the stability of sediment on the subaqueous Mississippi River delta front (MRDF). High sedimentation rates result in underconsolidation, slope steepening, and increased biogenic gas production, which are all known to decrease stability. Previous work has shown that sedimentation rates near Southwest Pass can exceed 1 m/yr with distributary mouth bar progradation at >70 m/yr. However, since the 1950s, the suspended sediment load of the Mississippi River has decreased by ~50% due to dam construction upstream. We examined bathymetric datasets, including historical charts, industry and academic surveys, and NOAA data, collected between 1764 and 2009 to identify changes to sediment accumulation rates in the MRDF. Analyses of these datasets show decreased progradation of the three major passes of the Mississippi River delta and decreased accumulation rates in deeper water. Nevertheless, recent high-resolution geophysical data suggest that seafloor movement is still occurring and wave modeling results indicate that waves with 1-year recurrence could be enough to trigger movement. These landslides pose a hazard to offshore infrastructure and our results highlight the complexity of seafloor failure processes and triggering mechanisms for submarine landslides on the MRDF.

For more information on this event, contact: 
Jessie Saunders
Event Calendar: 
Location: 
8610 Kennel Way La Jolla, CA 92037, US
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