Showing posts with label geophysics. Show all posts
Showing posts with label geophysics. Show all posts

Sunday, June 7, 2009

Work, Other than the Kiln

The project team has moved a lot of dirt besides that over the kiln.  This is a general description of other work at the site.  In the coming days, students and volunteers will write about their work on the blog.  These pictures and maps should allow the blog's readers to orient themselves to the site's layout.  If this is your first visit to the blog, before reading further, you might check out the map discussion and my comments about Mrs. Carol Wright.

Below are a photo of the Davenport
's 1890s home and site on the adjoining lot (viewer's right). The second image is a plan of the site on which I have drawn a map of our discoveries over the geophysics data.  I drew symbols that represent brick and stone masonry and foundations.  The black lines represent the 2 meter square grid that we mapped over the entire site to control our excavation record keeping.

The maps shows three major sets of features.  Kiln A is drawn as a green circle with some bricks drawn to show orientation.  I have outlined the other buildings and features using black-shaded boxes.  Looking at our discoveries, consider the following passage from Emma Cynthia Nielson's The Development of Pioneer Pottery in Utah (1961: 101-104):

"On Nov. 18, 1961, Mrs. Luella Adams, the wife of 
Thomas Adams, described the pottery as she 
remembered it.  We went out on the back porch
 of the home and looked over the yard.  
There was one old tree left from pioneer time, 
but everything else had been taken down and removed 
from the place. Mrs. Adams said that the pottery 
consisted of three log buildings which stood back in the lot 
and southwest of the present home. 
The building on the south held the clay; 
the next one was the factory; it housed the wheel.  
The third room was used to store the pots for drying.  
There was a basement midway between the home and the 
factory where the potter had his kiln."

Mrs. Adams's description helps us to understand the remains we have discovered so far.  We have found one kiln, the light foundation of a twentieth century shed or barn, a stone foundation for a much heavier building, and the cellar pit mentioned by Mrs. Adams.

While kiln A was the first discovered by Samantha and RenĂ©e, I do not think it was the first kiln built by the Davenports.  It is made of quality firebrick, which would have been very hard to find in 1853.  If the Davenports used firebrick in the first kiln, I expect it would have been used to line the inside of a structure otherwise built of locally quarried stone.  We are still looking for the other two kilns described in family histories.

While investigating the strong magnetic anomaly south of kiln A, Samantha, Mark, and Mike uncovered heavy stone foundations.  These courses of stone may be part of a single structure, including a small piece of foundation wall that I discovered during my excavations back in 2000.  That bit of foundation inspired my theory that the entire site was well preserved and worthy of intensive study.  This is a very heavy foundation, nearly three feet deep.  These stones were built to support something much more substantial than a small log cabin!  We are still debating why the Davenports built this building.

Andy was examining the anomaly in 6W42S when he discovered a deep pit.  We all think this pit is probably the cellar mentioned by Mrs. Adams in 1961.  In this picture, you can see the pit as Andy first saw it-- the northern 1/2 is black sediment full of charcoal.  The southern 1/2 of the unit is the orange clayey loam that we think was the ground under the topsoil in 1852 when the Davenport's started building their pottery.
During excavation, Andy discovered that the charcoal deposit was just the first layer in a deep and stratified pit feature.  The Davenport's dug into the subsoil and built the cellar, then through time they filled it with layers of soil and rubbish.  You can see the profile after excavation in this picture:
While Andy patiently excavated each stratigraphic layer in the cellar, he realized that for a time, the Davenports used the cellar as a disposal area for pots that failed in the kiln.  Andy found busted fragments of pottery.  Lots and lots of fragments of pottery.  Nine five-gallon buckets filled with sherds the size of quarters, nickels, and dimes. Other fragments were larger, including the warped and cracked crock bottom in Andy's lap in this picture:
Andy's most interesting observation so far is about the nature of the deposit. While carefully removing the fragments, he noticed that many of the larger fragments were actually stacked as they had been in the kiln.  Spurs, a kind of kiln furniture like a stilt, separated each pot or pan from those above or below.  From this observation, Andy concluded that some of this deposit was from a catastrophic failure in the kiln.  The potters carried entire stacks of crocks that had failed in the kiln and threw them into the cellar hole.  Some of the spurs he recovered are in this picture:
We are not yet certain if all the broken pots, pans, jugs, and jars in the cellar feature are from a single catastrophic event or if the Davenports threw things into the cellar over the decades of operation.  We will try to figure that out during analysis.

Looking at buckets and buckets and buckets of tiny broken ceramic fragments is a constant reminder of how badly we need support for the upcoming lab work.  I will use your tax deductible donations to support students working in the lab and for the scientific tests for their research projects.  If you are interested in learning more about how we put this project together, click here.  To make a donation to the Michigan Tech Fund into an account for the Utah Pottery Project, please click here.

Wednesday, May 13, 2009

Geophysics and Family History

Here are the results of today's magnetometry survey!  

In 2000, I interviewed Mrs. Carol Wright in Parowan.  Mrs. Wright is Thomas and Sarah Davenport's granddaughter.  She was born in 1908, which means she is 100 years old this year. Thomas Davenport died in 1888, twenty years before she was born.  Her father had worked in the pottery as a youngster, however, and she remembered the general description of the property even though the old adobe home and workshop buildings had been torn down before she was born.  

Below you can make a side-by-side comparison between the sketch I made with Mrs. Wright and the map of magnetic anomalies.  



I marked areas of interest to our excavation on the magnetic image below:


Based upon the magnetic anomalies, we think the basic description of the kilns' location and sizes are pretty accurate.  Family histories say that they were "about fourteen feet across."  There were several, perhaps three or four lined up in the back.  We are going to locate our excavation trench to expose one side of the kilns.  We'll leave the other side for future archaeologists, since they will certainly be better scientists than we are today.

We have begun surface collections of the site, grid by grid.  I expect we will start excavations on Friday.

Stay tuned!

Grids and gear!

We are underway in Parowan! The students all arrived by Sunday and we set up camp at the Five Mile Picnic Area. On the site this week, we set up the grid that will allow us to collect X, Y, and Z coordinates on all the data we gather during the dig.

Chuck Young is visiting with us today. He is a retired geophysicist at Michigan Tech. The Social Science department helped send Dr Young out to survey the site with us and teach the students about the Magnetometer.

The reason I asked Dr. Young to bring the Magnetometer is that we hope to see below the ground surface before we start excavation. We only have six weeks to dig. We really need to focus on the pottery-related features like the kilns. The magnetometer reads localized variations in magnetic fields as things interfere with the pattern of the earth's general one. Things like campfires burned in clayey dirt develop very strong magnetic anomalies. Something like a pottery kiln foundation should show up very clearly like a bright spot on the mapped readings.

At least, we expect so.

We are talking data right now and I will post a map of the readings later today!






The team on one of our first field trips. This one was about Iron County history.  They are climbing on an electric shovel from one of the twentieth century iron mines on the west side of the valley.



One picture of field camp!


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