Long Barrack Archaeology Update - February 2

February 2, 2024

Three excavation units were active this week- EU-2, EU-4, and EU-6. On Monday archaeologists had to document any damage from the heavy rain that fell last week; luckily there was minimal damage but the soil within the units remained wet through the end of the week.

In EU-2 archaeologists reached the pre-cultural occupation layers. The soil was the same clay found at the bottom of all previous units. There was a significant drop in artifacts, with only some shell fragments recovered. Archaeologists reached a depth of 130 cm below surface and only have two additional levels to excavate.

In EU-4, archaeologists excavated to a depth of 90 cm below surface. Artifact counts overall were lower than previous levels, however there were more ceramics recovered in this level than the previous level. Soil was beginning to become more compact and difficult to excavate through. There were also patches of eroded limestone that resembled an intentional surface, however there was not enough present to confirm this suspicion.

EU-6 reached a maximum depth of 50 cm below surface by the end of the week. Archaeologists encountered a continuation of Feature 8, which was previously encountered in EU-5. This feature is a burning episode consisting of ashy loam, an abundance of charcoal, and limestone rubble. The shape of the feature is oblong and when referencing documentation from EU-5 the entire feature was approximately 2 meters at its maximum length. After delineating the feature, the archaeologists began documentation, including photos and a scaled map. Additionally, at a similar elevation to Feature 8 archaeologists encountered two large stones extending east from the Long Barrack wall. These stones may be a part of a walkway, but further investigation is required.

Flat dirt surface inside an excavation unit
Figure 1. Excavation Unit 2, facing north.
Whiteboard and black step ladder inside of an excavation unit
Figure 2. Excavations at EU-4, photo facing north.
White board inside of excavation unit with rocky bottom
Figure 3. Excavation Unit 6 with Feature 8 on the right side of photo, facing north.

In the lab, artifact processing continued. This week we would like to share the types of metal fragments we commonly encounter while excavating.

Metal artifacts are commonly found within historic-age age archaeological sites across Texas. The current Long Barrack archaeological investigations have rendered thousands of metal artifacts; these include nails, fasteners, various hardware, and ammunition. However due to the poor preservation in the soil, metal artifacts (especially those manufactured from iron) have the potential to be heavily corroded and difficult to identify. This is caused by the type of soil in which the artifact was found, and degree of exposure to water and air. For example, soils with a higher concentration of gravel or sand, are very poor for preservation due to the increased exposure to water and air. However, soils like clay or silt with lower concentrations of gravel and sand lessen the soil’s permeability to air and water, making it ideal for preservation.

The images below depict examples of typical metal artifacts recovered from the current archaeological excavations. Figure 4 portrays an example of unidentifiable ferrous metal fragments. These artifacts are likely pieces of a larger object that have broken off, or of a single object that is heavily corroded. Figure 5 portrays examples of more identifiable artifacts, like nails, wires, and fasteners. Although these have corrosion present, the soil in which these were found may have not been exposed to the same level of water or air.

Fragments of ferrous metal next to a ruler for size
Figure 4. Unidentified/unidentifiable ferrous metal.
Ferrous metal wire, fasteners, and nails next a ruler for size
Figure 5. Ferrous metal wire, fasteners, and nails.