Sunday, June 28, 2015

Drills, Awls, or ??

Last week was both eventful and mundane. As our crew battled the flood waters nearly every day, we managed to make good progress on the excavation of the midden deposits surrounding the upper clay floor in Units 496N 512E and 514E. We also worked on midden remnants on the north side and began a new excavation unit on the northeast at 498N 516E. We made a good start on this last unit with the assistance of the Museum’s Student Naturalists, who visited us for the day on Wednesday (Figure 1). Our hope is that this new unit will expose the northern margin of the upper clay floor.

Figure 1. Student Naturalists dig in Unit 498N 514E.

We are not finding lots of artifacts in this area, which suggests that not much deer butchering or stone tool making went on in the vicinity of the clay floors. We did find several smudge (hide-smoking) pits cut into the upper clay floor, but this type of activity would not leave much stone tool debris behind. One exception to this basic pattern has been the discovery of several flint drills in the midden deposits close to the edges of the upper clay floor. These specimens look to have been heavily worked and re-sharpened many times. The three examples shown in Figure 2 are made from the three primary chert (flint) types we find at Burrell Orchard: Upper Mercer from Coshocton Co., Columbus-Delaware from northcentral Ohio, and Flint Ridge from Licking Co., Ohio. We have always called these objects “drills,” and indeed many were probably used for boring holes in wood, bone, and even stone. But a recent use-wear study of Burrell Orchard drills found in previous seasons revealed that several showed microscopic wear patterns from use on wet hide rather than on hard materials. Thus, it seems that at least some of these “drills” were not used for drilling at all, but instead were somehow used in the processing of animal hides. Perhaps they were used like the bone and antler awls (perforating tools) we commonly find at other sites.  So, we have another mystery to solve.

Figure 2. Drills from midden contexts near the upper clay floor (left: Upper Mercer chert; center: Columbus-Delaware chert; right: Flint Ridge chert).            

Sunday, June 21, 2015

Not One, But Two Floors!

Just one day into our first week of excavation at Burrell Orchard, we discovered another clay floor.  This feature is some 20 to 25 cm higher than the floor we found last season and is situated about 2.0 meters to the east.  If the radar images of the deep floor are accurate, then this new floor, designated as Feature 15-05, partially overlaps the deeper floor, Feature 14-11.    Both clay strata appear to be similar in make-up, that is, they were made from nearly pure yellow clay probably derived from subsoil deposits below the midden (Figure 1).  

Figure 1. Exposed southern section of yellow clay floor (Feature 15-05) in Unit 496N 514E.
So far, we have identified Feature 15-05 at about 30 cm bd in Units 498N 514E and 496N 514E.  The portion we have exposed measures at least 3.0 m north to south and 1.5 m east to west.  But we don’t have it all, since the clay deposit runs eastward out of the excavated area.  On Friday, we took three one-inch core samples at 50 cm intervals eastward from Feature 15-05 (Figure 2).  The results revealed that this new clay floor extends to the east between 1.0 to 1.5 m.  Interestingly, the core taken at 1.0 meter contained samples of two stratified clay floors, something we see evidence for in Unit 498N 514E.  Later in the afternoon we opened a new 2.0 x 2.0 m unit at 496N 516E to expose more of the floor.  Once excavation started we quickly found the floor at only about 15 cm bd in this new unit.
 Figure 2. Taking core samples eastward from the upper clay floor (Feature 15-05).
Meanwhile, Brian S.’s crew continued to carefully excavate 10 cm-thick levels of midden soil in Unit 496N 512E.  At about 30 cm bd, they exposed a large cluster of FCR, as well as two ground-stone tools: one a small hand-held grinding stone or “mano” with distinctive polish on the flat side and a large (3.0 kg) pitted stone.  As its name indicates, the pitted stone is marked by several distinct, regular depressions on several faces the look to have been made by the use of a rotating implement (Figure 3).  These pits appear too regular to have been made by simple whacking this stone with another stone to crack nuts or flake flint cores.  In fact, the likely purpose of these pitted stones remains unknown. 

Figure 3. Pitted stone found within midden deposits in Unit 496N 512E.

The discovery of at least two stratified clay surfaces is exciting and much unexpected.  It makes our excavation more complex but also very exciting.  Who know what will turn up this coming week!

Monday, June 15, 2015

Search for the Clay Floor Begins

Today we began our four week Archaeology in Action program at Burrell Orchard.  Despite the soggy conditions, we managed to make a start on three new excavation units located adjacent to two of last year’s units.  The reason we are returning to just about the same spot as last summer is to expose more of the Late Archaic clay floor feature found in unit 498N 512E last July.  This distinctive yellow clay layer was found near the bottom of the midden deposits at about 60 cm deep.  Its surface was burned to a bright red color in several areas, indicating the making of fires for cooking or some other function (Figure 1).  Along one edge of this clay floor we discovered an arc of post molds which may represent where the wall of a house was constructed.  By the look of things, it seemed that we had only exposed maybe one quarter or so of the floor, which appeared to extend

Figure 1. Exposed clay floor found in 2014. (White dots mark the locations of post molds)
southward into an unexcavated area.  So, this year we have returned to see if indeed this floor continues.  We hope to expose most of what is left and determine what it represents.  Perhaps it is a house floor or maybe a working surface for various open-air activities. In any case, nothing like it has yet been found in northern Ohio.

Today we proceeded to open the new 2x2m units and remove up to 20 cm of soil from the upper stratum or plow zone (Figure 2).  Here we found fire-cracked rock and chert (flint) flakes along with a few shards of historic dishware, mostly blue and red transfer-print ware. 

Figure 2. Work on new excavation units begins.

The find of the day was made by Marsha R. who turned up a complete triangular arrowhead, known as a “Madison” point, which was used from about A.D. 1200 to 1600.   It is a small point, possibly made from the broken tip of a somewhat larger arrow head (Figure 3).  It is made of lustrous gray chert known as Pipe Creek that outcrops just south of Sandusky, Ohio.    This point is some of the rare evidence we have collected for site occupants post-dating the Late Archaic settlers of the Burrell Orchard site.  These people of the Late Prehistoric period were apparently at this site for brief visits just a few centuries before Europeans entered northern Ohio and some 3500 years after the Late Archaic hunters and gatherers left.

Figure 3. Madison triangular arrow point found in the plow zone of unit 498N 514E.