Mississippi River Depositional System – Baton Rouge to New Orleans, Louisiana July 3–7, 1989 and New Mexico – Salt Lake City, Utah to Albuqurque ,

Published by the American Geophysical Union as part of the Field Trip Guidebooks Series, Volume 170.

The Mississippi, the largest river system in North America, drains an area of 3,344,560 sq km. This river system has been active since at least Late Jurassic times and has significantly influenced depositional patterns in the northern Gulf of Mexico. The modern river has an average water discharge of 15,360 cu m/sec, and average maximum and minimum discharges are 57,900 and 2,830 cu m/sc, respectively. The annual sediment discharge is estimated at 6.21x 1011 kg; the bedload consists of 90% fine sand, and the suspended load is characterized by 65% clay and 35% silt and very fine sand. Thus the Mississippi River carries a substantial sediment load annually, and a high percentage consists of fine-grained clays and silts.