Spoil Stratum

     In the 1950s, and again in the 1970s, highway construction crews used a dredge to dig a canal at the edge of the site. They dumped the dredged soil on top of the site. In some areas, the dredge reached from the top of the site all the way to the bottom strata. Artifacts from all layers ended up on the surface when the digging was finished. The dredged muck, called spoil, became the top layer at the site. It was a mix of dark soil with lots of roots, bits of shell and greenish clay.

The dark clay overlying the shell floor in this photo is spoil left over from dredging. The trowel in the photo is pointing to the north. Archaeologists often use a trowel pointing north in their excavation photos so they can orient themselves when looking at the picture later. Credit: LSU Museum of Natural Science.

     Many artifacts were in this layer. The bits of cord came from the spoil stratum, but originally they may have been at the bottom of the site. Late Archaic-style cooking balls also were in the spoil. Out of their original context, these artifacts lost some of their scientific value. On the other hand, archaeologists may never be able to dig to the bottom of the site because it is under water. These artifacts gave them a better idea of what they could expect to find if they could reach the oldest, deepest strata.