Friday, May 28, 2010

Exploring

Over the past couple of days, student crews have continued to excavate shovel tests to the north of the primary mission site, filling in the gap between the northernmost 18th-century midden deposit discovered late last week and the main site to the south. Several of these units fall within the modern floodplain, and one was placed in an area near fill deposits that were placed decades ago, extending higher ground as far as the riverbank. As can be seen in the photo to the right (pictured is Tonya Chandler), the uppermost layers of modern fill turned out to be underlain by an original ground surface that is characterized by a dark, organically-rich soil layer that appears to be a buried midden, but which produced only a single tiny shard of olive green glass.

In order to explore this deposit in broader context (and see what the underlying deposits looked like), we moved a few meters away to the edge of an old water-filled channel that had been cut all the way to the river, and cut a fresh profile roughly a couple of meters long along the upper bank (see photo to left; pictured is Jennifer Melcher). This profile showed us that the dark layer was underlain by light-colored sand and clay deposits probably dating to late in the Ice Age (much more recent than the bluff-top deposits where the mission site is located), and in fact these deposits were later found at the bottom of the shovel test above.

On Thursday three new shovel tests were finally set in to the east of the last line of tests excavated last year in the heart of the mission site. Given the extremely thick vegetation in this area, and the undulating topography along the steeper erosional edge of the high terrace above the second bottoms in this area, these units were located using a Global Positioning System (GPS) unit, combined with on-the-ground pacing from and between known shovel tests to the west (pictured at right is Jennifer Melcher taking GPS readings under the shadowy forest canopy). The area is full of poison ivy and mosquitoes, not to mention entangling vines and brush, but the two units were ultimately placed along the eastern edge of the high bluff, with a third located below the bluff in the midst of a vast field of broken bricks associated with the 19th-century steam-powered mill at Molino.

Two of these tests were opened late in the day, and will be explored further on Friday (pictured at left are Hallie Johnson and Morgan Wampler cutting roots).

A number of our recent shovel tests along the gentle slope to the north of the mission site have produced almost no cultural materials, and have come down on dense alluvial clay deposits that are virtually un-screenable without water. Below is a video of Tonya Chandler and Cody Poitevint using the waterscreening station to screen buckets of excavated clay.

video

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