Artifact Level Analysis and Places of History

Over the last few weeks, I’ve been working with David Pettegrew to finish writing the analysis of the survey data from the Pyla-Koutsopetria Archaeological Project (PKAP).  Followers of this blog know that this work is a long a term project and involves challenges both on the level of analysis but also organization and description.  In other words, we’ve been working to figure out both how to interpret our survey results, but also how do we organize and describe this data in way that is useful to scholars who are likely to ask different questions from the one’s that our survey set out to consider.

The biggest challenge is moving from the highly granular, artifact level analysis of individual groups of pot sherds to the level of historical time and space.  After all, very few important things happened in the space of a pot sherd or in a time framed absolutely by the life-span or production cycle of an individual vessel.  It is essential to aggregate sherds, space, and time in order to produce historical arguments.  The chronological ranges for artifacts through time depend, in particular, on our understanding of ceramic typologies based on the fabric, shape, and in some cases decoration.  These the chronology assigned to these various typologies are not necessarily meaningful in a historical sense and can be quite individualize to particular objects.

In other words, artifact level analysis is separate from the process of interpreting artifacts across the survey area as chronologically and historically meaningful groups.  Part of the interpretive process involves grouping artifacts together into more or less contemporary groups of object.  This process involves judgement on our part and cannot be applied in the same way across the entire assemblage.

As an example, our analysis of material representing activity across our site from the Classical to Hellenistic (BC 475 to BC 100) periods involves artifacts dated to at least 8 different, overlapping chronological ranges: Archaic-Classical, Archaic-Hellenistic, Classical, Classical-Hellenistic, Classical-Roman, Hellenistic, Hellenistic-Early Roman, and Protogeometric-Hellenistic.  In contrast, our analysis of activities on our site from the Roman period involves artifacts dated to three chronological ranges: Roman, Early Roman, and Late Roman.  Our ceramicist established the date ranges for individual artifacts largely based upon dates established through stratigraphic excavation and completely independent from our interpretation of the site as a whole.  It is common for individual classes of artifacts to receive have different chronological ranges. A sherd from a cooking ware pot might represent a vessel-type produced over a 500 year periods (say, any time during the Classical-Hellenistic period), whereas a fragment of fine ware might derive from a vessel produced during a 4 or 5 decade span of time (say, the early 4th century).  Each of the objects receives a different date and chronological range when documented in the survey area. As a very general rule, utility wares tend to be produced over longer spans of time than fine and table wares, but this has no necessary impact on how and when they were used.

The process of interpreting the artifacts documented by our ceramicist involves us aggregating these objects into chronologically, functionally, and spatially meaningful groups.  Past human activities took place in particular spaces and made use of object produced at different times and for different functions. To produce a picture of what happened in the past at our site that has meaning within these human terms, it is necessary to group together material with different date ranges into assemblages that have meaning in human terms.

For example, here are various maps showing some of the periods aggregated to produce our analysis of the Classical to Hellenistic period at our site:

Archaic-Classical Period

Classical Period

Classical-Hellenistic Period

Classical-Roman Period

Hellenistic Period

Hellenistic-Early Roman Period

To understand trends at our site from Classical to Hellenistic period, the data contained in each of these maps must be analyzed together.  Occupants at our site may have used coarse ware datable only to the Classical-Roman period alongside table wares dated more narrowly to the Classical period.  The Classical period table ware may have represented a households investment in public display, the same household may have stored their agricultural wealth in a series of amphoras that have forms and fabrics used for over 500 years.  To establish the potential spatial relationship between these two activities in an archaeological setting, it is necessary to plot artifacts assigned to different chronological ranges across our site in order to produce assemblages that reflect historical activities.

This task is central to the analysis of artifact level survey data and is the key interpretive move in mediating between the results of archaeological work and historical events in the past.  Our goal as we work to prepare this kind of analysis for publication is to keep this interpretative move as transparent as possible.  Transparency, while sometimes tedious for the reader, opens our analysis for critique on both evidentiary and methodological grounds and reinforced the idea that archaeologists produce the landscape that they interpret.

David Pettegrew’s Setting Stage for St. Paul’s Corinth Available as Podcast or Streaming Video

For those of you who could not make it to the David Pettegrew’s 2nd Annual Cyprus Research Fund Lecture, fear not!  We have made David’s lecture available as both a downloadable podcast and as a streaming video.

Here’s the podcast.

Here’s the video.

David’s two days on campus were really exciting.  Not only did he speak to over 50 faculty,undergraduates, graduate students, and members of the community on the Thursday afternoon talk, but he also contributed to the history department’s “brown bag” lecture series on Friday.  At his Friday talk, he presented a great primer to intensive survey archaeology and discussed the ideas of “source criticism” as applied to ancient material culture.  Finally, David took a couple of hours and read Latin with some of our graduate students and undergraduates at our weekly “Latin Friday Morning” reading group.

It is always gratifying to see how much interest there is in the Ancient Mediterranean at the University of North Dakota.  So, if you enjoyed the lecture with here at UND, thanks for coming out! And if you enjoy the lecture via the streaming video or podcast, thanks for listening!  I also should thank Chad Bushy and Caleb Holthusen from UND’s Center for Instructional and Learning Technologies office for not only preparing the video and podcasts, but trouble shooting during the live webcast.

And, finally, thanks to David Pettegrew for agreeing to spend his fall break with us at the University of North Dakota. For more on his research and the Roman and Late Roman Corinthia, check out his blog Corinthian Matters.

David Pettegrew on Corinth! Live on the Interwebs!

Join us today for the 2010 Cyprus Research Fund Lecture: David Pettegrew’s “Setting the Stage for St. Paul’s Corinth: How the Isthmus Determined the Character of a Roman City.”  The talk is at 4 pm today in the East Asia Room of the Chester Fritz Library.

If you’re not from Grand Forks, FEAR NOT!  We’ll also stream David’s talk for free on the interwebs!  Here’s the link.  Just log in a guest.  If you’re watching remotely and have a question for David, just Tweet it to me.  Here’s my Twitter account (@billcaraher) and use the hashtag: #CRF2010 at the end of your post.

Some Notes on RBHS Analysis of the Pyla-Koutsopetria Survey Data

No RBHS is not a local high-school to whom I’ve outsourced PKAP data analysis, nor is it a new type of digital hi-def television.  Those letters stand for Rim, base, handle, sherd and represent the basic parts of a ceramic vessel.  Since most of the vessels one finds in survey and even excavation are not whole or are broken and mangled, documenting the rim, base, handle, and sherds from each vessel is an important way to understand how we as archaeologists are able to identify an particular object and assign it to a date, function, and even, sometimes, place of manufacture. It is also helpful in secure, stratigraphic contexts (that not in an unstratified survey context) for identifying the minimum number of possible vessels of a particular type because we know that some kinds of vessels on have, say, one-handle, then a four handles would represent at least four vessels of this type.

David Pettegrew’s research has really set the stage for applying this kind of analysis to the PKAP survey data. He has argued that certainly highly diagnostic artifact types (for example Late Roman 1 amphora handles or Late Roman “combed ware” body sherds) can distort the chronological distribution of material at a site.  Periods characterized by less diagnostic artifact types tend to be less easily associated with a narrow chronology or function and under represented in relation to period defined by more easily identified vessels types.  So isolating the way in which particular periods become visible using our Rim/Base/Handle/Sherd analysis becomes an important to critique our survey data.

Fortunately, the basic system that we use to document our ceramics, the chronotype system, took into account rbhs. The chronotype system required the ceramicist to separate and document as a group, called a batch, according the extant part of each type of vessel present . In other words, we counted in one batch all of the rims from, say, a Roman Amphora and in another batch all the handles from the same kind of amphora. This has allowed us to parse quite finely the character of our assemblages and its relationship to our ability to identify particular types of artifacts based on their individual parts.

So here are some basic observations:

• Of the 19 periods with more than 20 sherds collected using our standard survey procedure, 13 counted the majority of artifacts as body sherds. In other words, for most periods, body sherds represent both the most common and the most chronologically diagnostic type of material.
• Only for the Archaic period were the majority of artifacts identified by one part of a vessel, and these almost all came from one type of vessel, so-called Archaic basket handled storage jars.
• Of the 258 chronotype (that is discrete types of artifacts) that produced extant parts (some chronotypes, like shells or wall plaster fragments, do not produce extant parts that we can easily record), 138 of 55% of these chronotypes were identifiable based on only one extant part. 76% are recognized by only two extant parts and 90% by three. 99% by four extant parts (mainly RBHS).  In other words, most artifacts are only recognizable by one part of the vessel.
• It is interesting to note that the number of chronotypes associated with a particular period has almost no influence on the average number of extant parts by which a vessel is identified. Large number of chronotypes identifiable by a large number of extant parts (4+) come from Roman (40), Late Bronze Age-Hellenistic (18), Ancient Historic (39), Hellenistic-Early Roman (24) vessels. At the same time 4 or more extant parts also appeared for periods with fewer chronotypes, like Classical-Roman (6), Late-Cypriot II-Late Cypriot III (4), and Post-Prehistoric (4).  This means that while the majority of sherds from each period are body sherds, they nevertheless have vessels that are identifiable based on other parts of the artifact.  In other words, our ability to date artifacts to a particular period is independent from the number of vessels with identifiable extent parts. Some periods have three or four chronotypes with lots of identifiable fragments; others have 25 different chronotypes with a mix more and less easily identifiable artifact types.  There does not seem to be a pattern.
• Far more central to the number of parts of the vessel that we can identify is the kind of vessel and their function. Kitchen/Cooking ware produce the most possible extant parts (4+) followed by coarse ware and amphora chronotypes (3.8). Medium coarse ware produced 3.5, while pithos, semi-fine, and fine all produced 2.4 or fewer extant parts per chronotype. This likely has more to do with the shapes of the vessel than the size of the vessel.

This kind of analysis may seem tedious and complicated, but it is important to understand how bias in our ability to identify a particular type of artifact can influence the kinds of chronological and functional landscapes that we create from survey data.  In examining our data in this way, we can really see the point of contact between what our ceramicist does in placing artifacts in particular classes and our historical reconstructions of the landscape.  The entire world of Pyla-Koutsopetria is literally born from the data gleaned from individual artifacts.

Even More Experiments in Intensive Pedestrian Survey

Even more guest-posting brilliance from our esteemed guest blogger, David Pettegrew, the co-director the Pyla-Koutsopetria Archaeological Project and the 2010 Cyprus Research Fund speaker.  Be sure to check out his posts on Tuesday, Wednesday, Thursday, and yesterday.

Over the last few days (here and here), we have been discussing the results of an experiment we carried out 2010 in order to assess the relationship between the number of artifacts we see in pedestrian survey and the number actually on the ground.  You can read about the first two phases of these experiments here and here.

Today we consider the kinds of artifacts that we observed during total collection and the sorts of material that made up the surface matrix.  When we set up the experiment, we consciously decided not to collect artifacts via the chronotype sample as we normally do in our pedestrian resurvey.  What crueler thing could one do to the project ceramicist than overwhelm him with 1,000+ surface artifacts? (After all, the logic of sampling is to manage human resources more effectively.) Because we didn’t identify the artifacts from the total collection grid according to chronotype as we did for the survey units, we limited the kinds of comparisons we can make between the pedestrian survey sample and the total collection.

Even still, there were still some things we could do to give us a sense of the kinds of material on the ground, especially their fabric and functional attributes.  How much of the surface assemblage of a high-density unit at Koutsopetria consists of cooking ware, coarse wares, coarse wares with surface treatment like combing, and table wares (slipped or unslipped)?

To address this question in part, we sorted all pottery from each total collection unit into three basic fabric classes: semi-fine and fine ware (whether decorated or not), cooking ware, and medium-coarse and coarse wares (including amphora sherds).  The results below show the count of each of the categories in each of the total collection grid squares and give in parentheses the percentage of that fabric group in terms of the total number of potsherds in the unit.



 

Fine ware constitutes 7.6% to 15.4% of the number of potsherds in each subunit; cooking ware only 1.7% to 5.4% of the total number of potsherds; and coarse wares consistently 80.2-87.2% of the overall assemblage.  Unsurprisingly, for a predominantly Late Roman assemblage, the great majority of the sherds are coarse, a small percentage are fine, and tiny percentage are cooking.  The disparity between coarse wares, on the one hand, and fine and cooking wares on the other would have been even greater had we compared weight instead of count, since most fine and cooking ware sherds are thin-walled and small.

We also counted the “parts” of the vessel according to the standard ceramicist categories of rims, bases, handles, shoulders / necks, and body sherds.  Rims represented 2.9-7% of the total sherd count, bases less than 2.2%, handles from 2.2 to 5.3%, neck and shoulders typically less than a percent. Body sherds typically represent over 90% of the surface assemblage.

Finally, we tabulated the data in a slightly different way, breaking down the surface assemblage for each subunit by both fabric group and part.  The results shown in the table below suggest that this Late Roman assemblage includes for fine wares mainly body sherds (73.8% of fine wares) and rims (19.5%), for cooking ware mainly body sherds (84.5% of cooking wares) and handles (6.9%), and for coarse ware mainly body sherds (92.9% of coarse wares).  

Coarse ware body sherds make up 79.5% (n=1474) of the total number of sherds (n=1,854) counted for all 4 subunits.  By contrast, fine ware rims make up 2.2% of the total pottery assemblage and cooking ware rims form only .11% of the total pottery assemblage!!!  The 71 fragments of slipped and glazed fine ware (i.e., not including fine ware lacking clear glazing or slip) represent only 3.8% of the total number of potsherds counted (n=1854).  These few black glazed Classical-Hellenistic sherds and red slipped Roman-Late Roman sherds are the typical objects used to provide most of the chronological information for dating archaeological sites but they represent less than 4% of our surface assemblage of this unit at Koutsopetria.

Finally, it is worth asking what percentage of coarse body sherds have surface treatments and decorations like grooving, combing, and ridging — the kinds of surface treatments that usually lead to them being collected in most regional surveys.  To address this question, we counted the coarse sherds for two of the subunits (G1 & G15) with spiral grooving, combing, or wheel ridging.  The 66 sherds represent 12.5% of the 526 coarse body sherds from those subunits and 9.8% of 672 total sherds from those units.  These “diagnostic body sherds” then are more visible than glazed and slipped fine ware but still quite unrepresentative of the surface pottery as a whole.

I suppose our next steps with the results of these experiments are to compare them with 1) the chronotype sample from the broader survey, and 2) the data from subsurface excavated deposits.  I think the interesting results of the experiment certainly justified the time it took to totally collect the subunits and will allow us to understand how close our chronotype sample is to the population of ceramic artifacts on the ground.

More Experiments in Intensive Pedestrian Survey

More guest-posting brilliance from our esteemed guest blogger, David Pettegrew, the co-director the Pyla-Koutsopetria Archaeological Project and the 2010 Cyprus Research Fund speaker.  Be sure to check out his posts on Tuesday, Wednesday, and Thursday.

Last Thursday, we introduced the survey experiment that PKAP conducted in June 2010 to assess the relationship between the number of artifacts that we see when we walk across a survey unit and the number of artifacts actually on the ground.  In other words, we wanted to assess how effective our survey methods are in actually assessing what was on the ground.  On Thursday, we compared the artifact densities detected by the project’s untrained student fieldwalkers to those counted by trained senior staff members.  Today we will discuss the second phase in our 2010 experiment, an assessment of the total population of all artifacts on the surface of select subunits.  This part of the experiment was designed to give us a total count of all surface artifacts that can be compared with the artifact counts reported in yesterday’s discussion.

We began by selecting four 10 x 10 m subunits based on the densities of the 10 x 10 m artifact densities counted by the experienced senior staff members.  As with past experiments (published in the RDAC 2007), we selected our 4 subunits to represent the range of density variation: the lowest density quartile (G15), highest density quartile (G9), and two middle quartiles (G1 and G6).  Each total subunit was 10 x 10 m, representing 1/16 (6.25%) of the 1,600 sq m survey unit.

To vacuum a high-density unit, you really have to spend a lot of time picking individual artifacts off the ground.  For each of our units, students Andrew, Zane, Valerie, and Luke, and I  walked very slowly in adjacent passes across each selected square gathering together in 1 or 2 corners of the unit all the artifacts present.  An initial pass was never enough for we observed how many artifacts we missed initially.  Usually two additional passes were necessary to vacuum the surface completely, and each pass involved either crawling on hands and knees, or bending so that you had a closer view of the ground.  I have to admit that my back and neck got sore after a while of this.

The results of this “total collection”, shown below, are interesting to compare with the “pedestrian survey counts” discussed yesterday.  You have to keep in mind with the comparison that the pedestrian counts represent a 20% sample of each subunit while the total collection counts represent a 100% sample.  You have to multiply the pedestrian count by a factor of 5 to estimate the “total putative count” (i.e., an estimation of what the total count would be for 100% of the unit) for the pedestrian-walked unit.

The first outlined set of grid units below shows the total counts from each of the total collection units.

The second set of grids compares the total collection counts with the pedestrian survey counts in parentheses (multiplied by 5 to create the 100% putative sample).  

The third shows the factor difference between these two types of counts.  

Here is where it gets even more interesting.  We can estimate that the 940 artifacts experienced fieldwalkers counted through pedestrian survey across the entire unit (i.e., the pedestrian counts from 4 walker swaths) would produce a putative pedestrian survey count (factoring for the 20% sample) of 4,700 artifacts.  In other words, had we walked 100% of the unit, we would have counted about 4,700 artifacts.  Now, if total collection (vacuuming) produces on average 2.96 times the number of artifacts as pedestrian survey, we can estimate that there were 13,212 artifacts actually on the surface of the ground.  To provide some perspective, we collected and brought back to the museum 8,788 total artifacts from the 252 grid squares of Koutsopetria and 19,657 total artifacts from our survey of the entire Pyla-Koutsopetria area.  A single survey unit at Koutsopetria totally collected would produce 1.5 times the number of artifacts sampled from all 252 grid squares at Koutsopetria and .67 of the total artifacts sampled across the entire Pyla area.  If we were to apply the same multipliers to all 252 forty x forty meter grid squares, i.e., the main part of the site of Koutsopetria, the total artifact count of 19,182 would produce a putative total count of 95,910.  Our estimated total population of artifacts (based on the 2.96 factor) is at least 284,894 (and in reality, poor visibility in many units often limited our sample to 50% of the ground).  This is *why* sampling is important!

As for TIME, total collection requires a huge commitment.  Although we (for clarification here, “we” means David – Bill) initially considered surveying all 16 subunits, i.e., an entire 40 x 40 m unit, this proved unrealistic given the time it took for 5 individuals to vacuum a single subunit: 1.5 hours each for G1 and G6, 2 hours for G9, and 1 hour for G15.  Using the total time it took to hoover 25% of the grid square (6 hours) as an index for hoovering this unit, we estimate that 5 individuals could hoover a high-density 40 x 40 m unit in about 24 work hours or well over 100 work hours!  If the typical survey work day is 6 hours long (say, 6AM-noon), it would require 4 full days of a team collecting artifacts from the surface.  Truly this would be an incredibly time intensive task!  By contrast, sampling 20% of the unit through pedestrian survey takes about 20-30 minutes.  In this perspective, total collection requires 72 times more time than pedestrian survey collection!

One final comparative result is interesting to note here.  The “other” category increases dramatically through total collection, including numerous pieces of ancient glass (9), lithic stone artifacts (7), shells (24), slabs (13), gypsum (141), ceramic bricks (2), stone vessel (1), marble revetment (3), and a ceramic tessera or gaming piece.  Although total collection was time intensive, this sort of qualitative information is quite useful in filling out our picture of the overall survey unit and indicates something of the functional variability within each survey unit.

Tomorrow, we will conclude our discussion of experiments with an overview of ceramic fabric categories.  Stay tuned!

 

Experiments in Intensive Survey at Pyla-Koutsopetria

Another guest post from our esteemed guest blogger, David Pettegrew, the co-director the Pyla-Koutsopetria Archaeological Project and the 2010 Cyprus Research Fund speaker.  Be sure to check out his posts on Tuesday and Wednesday.

When I announced my plans to conduct a survey experiment where we would “vacuum” an entire 40 x 40 m unit, Dimitri and Bill both laughed and told me that I had to try it simply for its absurdity.  The 40 x 40 m survey unit was our standard size for the 252 units that we laid out across the Koutsopetria plain .  As far as survey units go, 40 x 40 m (or 1,600 square meters) is a relatively small unit compared to that typically employed by those who conduct distributional survey.  At the same time, when on the group, 40 meters is still vast when compared to the dimension of most lived space.  After all, a 40 x 40 meter unit is over 130 square feet on a side and over 17,000 square feet which makes a single survey unit much larger than even the most over-sized suburban McMansions.  The reason that my suggestion was humorous, however, had to do with the method I proposed for collecting artifacts.  In our typical pedestrian survey, we only looked at 20% of the surface of the unit (for a more reasonable and suburban 3,400 square feet) and only collected each unique artifact from what we saw on the surface.  My proposal was more extreme: get down on our hands and knees and completely “vaccum” (or “hoover”) all the artifacts from 100% of the unit to produce an exhaustive (and exhausting!) total collection rather than a quick 20% sample.

Why?  I had the suspicion that the amount of artifacts we see when we walk across the unit is but a fraction of the total number of artifacts actually on the ground.  The suspicion was based on experiments conducted in 2004 & 2006 where we ‘vacuumed’ artifacts from a 5% sample of our 40 x 40 m units, producing on average artifact counts that were 4 times greater than that produced through our 20% sample using pedestrian survey.  We also proved through these experiments that the substantially larger number of artifacts did not really contribute much new chronological or functional information that warranted the additional investments of time and energy.  We published a report on those experiments in an article by the authors in the Report of the Department of Antiquities, Cyprus 2007.  However, we were aware of the substantial fluctuations of artifacts within 40 x 40 m units and the risk of a 5% sample (80 sq m) being unrepresentative of the unit as a whole (1600 sq m).  The point of our 2010 experiments, then, was to test the results with a much more robust sample.  While I initially wanted to vacuum 100% of the unit, time constraints prohibited me to vacuuming 25% of the unit.  Even still, 25% of the unit is 5 times greater than what we sampled in 2004 and 2006.

Due to the limited time for fieldwork this season (and time constraints were one of the reasons that we sampled the units to begin with!), we could only resurvey a single unit placed in the highest-density area immediately northeast of the excavated apse of the early Christian basilica.  We picked this unit to overlap with our very first Discovery Unit, a grid square of 40 x 40 m surveyed in 2004 northeast of the enclosed excavated part of the site of Koutsopetria.  We divided the 40 x 40 unit into sixteen 10 x 10 m subunits, each representing 6.25% of the overall unit area (1,600 sq m).  The grid squares have been given the prefix of G followed by a number between 1-16, as the following plan shows.

In our interest in comparing artifact counts noted during pedestrian survey—where a surveyor walks across the unit examining a 2 m wide swath and counting all pottery, tile, lithics, and other artifact types—with the total population of artifacts actually on the surface, we implemented two stages to the experiments.  The first stage (pedestrian survey) we will report on today.

We began by having four fieldwalkers walk across the unit, recording all artifacts visible in their swath, giving a 20% sample of every 10 m of space across a 40 m transect.  We collected ‘sub-tract’ artifact counts every 10 meters to produce density figures for each of the subunits (G1-G16) and assess the fluctuating density of pottery, tile, and lithic artifacts within a survey unit.

We collected the data for pedestrian survey three times.  The results of these three separate pedestrian survey exercises are shown in the four figures below.  The numbers represent artifact counts of each type (pottery, tile, other, and total), and the gray shaded columns with orange numbers represent the total artifact count for the swath per fieldwalker.  

The first time (see figure 1.1 below) a group of untrained students walked the units—Andrew, Luke, Valerie, and Zane—who who had only seen artifacts at the museum and not in their “natural” (or better, archaeological) contexts.



A steady light rain the following day provided the chance for these same students to rewalk the unit a second time (see figure 1.2 below) with artifacts slightly more visible as a result of the washing of the dust.

Finally, a group of experienced fieldwalkers—David Pettegrew (DKP), Dimitri Nakassis (DN), and Bill Caraher (WRC) —walked the unit and counted artifacts (see figure 1.3).

Hence, the variables in these three episodes of pedestrian survey were experience, and, to a lesser extent, the amount of dust and dirt obscuring the surface of the pottery.  Otherwise, between episodes environmental factors were constant, as were methodological factors and figure 1.4 shows the average of all the counts produced.

We walked these units on June 9 and 10 and each took between 15 minutes and half an hour.

Comparing simply the total artifact counts (the bottom right grid within each of the outlined figures), it is interesting to note that the rain appears not to have made a difference overall in density counts between units [1.1] and [1.2].  Although one student count went up significantly after the rain (LHM: 118  243), and another student count was slightly greater (AMH: 200  241), VAW’s total counts were essentially unchanged (335 to 334), while ZRB’s total counts actually declined (238).

As far as the other variable (experience) goes, there were some significant disparities between experienced walkers and inexperienced walkers as evident in counts for particular grid squares (compare G1 for [1.1] and [1.3]).  Otherwise, the overall artifact counts were comparable for the units: the lowest-density and highest-density subunits occurred between all three walking episodes.  If we look at total artifact counts for each unit as a whole, students counted 942 artifacts in [1.1] and 1056 artifacts in [1.2] while experienced walkers counted 940 artifacts in [1.3].  That is remarkably close!  

We noticed one major difference, however, in the “other” category, which includes all artifacts besides pottery and tile: marble revetment, gypsum, shell, ancient glass, and ground stone agricultural implements.  The experienced field walkers noted 2-4 times the number of other artifacts in [1.3] than inexperienced fieldwalkers in [1.1] and [1.2].  An experienced walker counted 4 lithic artifacts (chipped stone & ground stone) in G3 and G7 that an inexperienced walker missed.

Processing Pyla-Koutsopetria Pottery

Another post with help from our guest blogger and 2010 Cyprus Research Fund lecturer, David Pettegrew. Check out the first in our series of posts here.

In 2010 the Pyla-Koutsopetria Archaeological Project was above all the year of the potsherd.  Excavations generate a lot of material.  Our thirteen Excavation Units in 2008 and 2009 generated pottery at rates faster than our poor ceramicist, Scott Moore, could read and pottery began to pile up at the museum while we were finishing our work.  We promised Scott that 2010 would be different and we were fully committed to getting the material read.  In fact to our surprise, some bureaucratic snafus getting our permits to do fieldwork prevented the collection of additional materials, and allowed us to devote more time to processing the material collected in past seasons.  So rather than venturing out into the field, we spent each mornings out at the museum processing hundreds of bags of ceramic artifacts and our afternoons processing digital data from previous years.  The result of all this is that we caught up.

Now to the untrained eye, ceramic processing looks like a bunch of people doing just one or two different tasks.  If you had come to Larnaka and peeked into our work space, you might only discern a couple of obviously different activities say, washing vs. analysis.  But the team was conducting a wide range of different tasks related to the finds.  The most obvious and important preliminary activity involved washing artifacts.  There were a slew of them to wash, 147 bags to be exact, each bag containing dozens, sometimes hundreds of artifacts.  Student enthusiasm for washing artifacts declined over a period of a week and a half but that is to be expected.

Dallas Deforest photographed every catalogued artifact at a resolution high enough to be published.  In 2010, Dallas took over 1,200 digital photos of our catalogued artifacts to join the 3,100 artifacts taken in previous years.  Two of our PKAP veterans from 2009, Becky Savaria and Melissa Hogan, began the process of labeling these photos.  In late June, David spent about 10 additional hours getting all the photos in order.  Now we have an archive of 4,300 digital photos of the 700+ catalogued artifacts and uncatalogued artifacts.

Building 13 was the central hub of ceramic analysis.  Our co-director and golden child, Scott Moore, spent 3 weeks analyzing the ceramics from excavations including those occurring in the 1990s at the site of Koutsopetria and our more recent ones at Koutsopetria and Vigla.  Scott analyzed the pottery in two different ways.  First, he “scanned” less significant contexts from stratigraphically unimportant matrices like the plowzone, the kinds of contexts where reading pottery in great detail is not all that beneficial.  “Scanning” involves 1) sorting pottery into broad categories based on fabric groups (e.g., fine ware, cooking / kitchen ware, and coarse ware); 2) setting aside the most distinct and diagnostic artifacts; 3) making basic observations about the context as a whole on a scanned unit form; and 4) analyzing in greater detail the most diagnostic pottery.  Indeed, scanning is common in Mediterranean urban excavations where excavations might easily produce hundreds of thousands of artifacts (or millions).  The more important contexts Scott read more thoroughly by identifying every artifact with a specific chronotype.  A chronotype is simply a specific, limited identifier for known groups of pottery that combines date, potential functions, shape, and appearance.  The point is that Scott read (and this is an estimate) 200 contexts while in Cyprus this year.

The other activities going on in Building 13 were data management (Bill), illustration (Becky Savaria, Melissa Hogan) and artifact cataloguing.  David, Dimitri, and several students wrote more detailed catalog entries for particularly significant finds from the survey and excavation.  In 2007, we completed a formal catalogue of the most significant artifacts from our archaeological survey.  This year, we completed the catalogue of artifacts recovered in the two years of excavated soundings.  The combined total of catalogued artifacts now exceeds 700.  While it is unlikely that we’ll be able to publish a catalogue of 700 different artifacts, we plan to eventually release this complete catalog in a digital form and publish on paper a smaller number of “greatest hits”.

We recorded the following information for each artifact in our catalogue.

Artifact Number:

Dimensions:

Munsell:

Description Fabric:

Description Shape:

Description Decoration:

_______________________________

Besides this work, we did a variety of more specialized work.  Sarah Lepinski and Bill completed the documentation of the architectural and painted plaster from the excavated area at Koutsopetria producing a complete catalogue of material for publication.  Sarah’s pain-staking examination of the plaster from the excavated area has revealed not only several phases of reconstruction and redecoration that remained obscure in the stratigraphic record, but also import clues about the architecture and even construction techniques used in the building.  Nearby, several students completed a special project analyzing artifacts from the plowzone which we plan to report on later in the week.

In sum, at the end of the 2010 season, we can offer this summary of the quantity of artifacts processed by team PKAP between 2003 and 2010:

Total number of units processed (from both the survey and the excavation): 711.  Each unit represents a discrete archaeological context either in terms of stratigraphy, method, or horizontal space in the survey area.

PKAP Pottery Processing by the Numbers

Batches of artifacts processed: 12,900.  Scott divides the pottery from each unit into batches of similar types of artifacts based on the artifact’s fabric, the part of the vessel represented, and the chronotype.  Over the past 8 years Scott has processed slightly fewer 13,000 batches.

Total number of artifacts processed: 37, 141.  Each batch has an average of 2.9 artifacts.

Total weight of artifacts processed: 1,482.1 kg or 3,208.7 lbs or over 1.5 tons of pottery.

Artifact Photos Taken: 5,500

Artifacts Catalogued: 727

 

PKAP Season in Review

As promised yesterday, this week will features (gasp!) a guest blogger, Dr. David Pettegrew.  David is the co-director of the Pyla-Koutsopetria Archaeological Project and over the next three days he will report on the various work conducted by the project this season.  David will be visiting us here in Grand Forks in October as the annual Cyprus Research Fund Lecture Speaker.

Perhaps the greatest misimpression about archaeology today is that it mainly consists in digging holes in the ground.  Excavation is the perhaps the most glorious and maybe even the most exciting, component of archaeological work (although some people find the analysis of the results of survey and excavation the most exciting. – Bill), but it’s still only a tiny part of the pie.  As you may have gathered from this blog, our own work rarely involves traditional excavation.  In the field, we’ve devoted lots of time to pedestrian survey, geophysical prospection, aerial photography, illustrating, and recording notes—and lots of time to processing all those artifacts, i.e., washing, analyzing, cataloguing, photographing.  Beyond the field season, we spend most of our time processing data, reading, writing, and publishing their finds, and preparing for the next field season.  Students who join us every summer in Cyprus for 3-4 weeks may forget that most of our work goes on for months after Cyprus.  And the work is harder, not easier.

This morning we mailed a copy of our 2010 final report to the Cyprus Department of Antiquities.  If the press release posted yesterday represents a kind of quick and dirty abstract of our work in the Pyla area, the annual final report provides in excruciating detail a full outline of our work.  Anyone who does archaeological work has got to produce these things, and they’re not fun to write.  This year’s report with contributions by Scott, Bill, David, and Sarah Lepinski, was about typical in numbering 77 single-spaced pages.  They have been longer (100 pages) but they’re rarely shorter.  Why so long?  What we do is complicated and has to be explained in enough detail that it makes sense to anyone reading the report in the future.  We tend to provide more detail in our reports than we need for our articles which does make it easier at a later point to create papers about our work.

As we’ve discussed here and here, the point of our 2010 field season was completing the analysis of artifacts from our 2008-2009 excavations of the sites of Koutsopetria and Vigla.  We also anticipated being able to conduct additional fieldwork at these sites.  As it turned out, for reasons we’ve explained elsewhere, we were unable to excavate and we received permission only at the 11th hour for our other fieldwork activities.

Even still, as we outlined in our final report, we’re not disappointed and did manage to accomplish the following tasks:

1. We finished a preliminary “read” of all the artifacts collected during intensive survey (2003-2007) and excavation (2008-2009), cataloguing in greater detail about 300 finds from survey and excavation.

2. We finished documenting and illustrating the area excavated by Maria Hadjicosti. We have posted about that here and here.

3. We took low-altitude blimp photographs of the excavated area and the landscape. We have already posted the results of that—including the disastrous flight of …. — here and here.

4. We continued documenting subsurface remains using ground penetrating radar.

5. We conducted limited resurvey of ridges to the west of Koutsopetria.

6. We conducted experiments designed to calibrate the results of the intensive survey in the study area.

Such activities lack the dazzle of opening another excavation unit (as exciting as that can be) but, we would argue, prove more important in the long run for our understanding of the site and create a solid foundation for the final publication of our fieldwork now in preparation.

In the next few days we will be providing some behind-the-scenes glimpses of the kinds of post-processing work that we have been doing in the month since our field season ended.  Since we have already written about #s 2-3 elsewhere, we will focus our comments on #s 1, and 4-6.  Enjoy.

Provisional Discard

David Pettegrew and I have been visiting a photographing a settlement in the Corinthian countryside.  Today we observed a few commonplace examples of what archaeologists call provisional discard.  That means discard that occurs in an orderly fashion after an object is no longer needed for its primary use. 

Provisional discard is part of the numerous processes through which artifacts become part of the archaeological record from their place in more everyday life.