Dredge Pit Vibracore

In 1932 a dredge pit was excavated along the south shore of Lake Pontchartrain. The pit was dug to 19 meters, in 7 meters of water. Since the 1930's, sediment has slowly accumulated in the dredge pit, which was dug down to the stiff Pleistocene surface. A photograph of a sediment core (vibracore) acquired from a dredge pit shows a sharp contact between recent fill material and the weathered clays of the Pleistocene surface. The recent sediments are laminated with little to no bioturbation or other major discontinuity, indicating an undisturbed section. Since the bottom of the pit is below storm wave-base and has restricted circulation, it provides a record of material entering the lake and settling to the lake bottom since the early 1930's.
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