The Archaeology of the Mediterranean World

More on Thisvi in Boeotia

The plan is to wrap up a draft of the Thisvi paper by the end of today, and it looks vaguely possible.  This weekend, I ran a bunch of queries on the finds data to attempt to determine the relationship between the ancient and post-ancient material on the site.  As our Archaeological Institute of America panel is supposed to focus on the post-Classical levels at well known sites, then it seemed better to focus on the post-Classical material from Thisvi (and ignore, mostly, the idea that surface material, no matter what the chronology is always "first out"). 

The first step to my chronological analysis was simply to look at the distribution map generated by plotting the artifacts by period across the sites and known transects.  I've put up versions of these maps  before in a slightly modified form.  The maps below include data from the more intensively collected sites (these are dots that do not appear in any survey transect) and in the circular collection units surveyed in the first year of fieldwork near the Hellenistic walls of Thisvi.  Each dot represents one artifact.  Their location within survey transect is arbitrary.

 
 

The first map (blue dots) represents Classical-Hellenistic material, the second (red dots) Late Roman material, and the third (gold dots) Byzantine-Medieval material.  They clearly show that by the Late Roman period, a significant contraction in the distribution of material occurred around the city of Thisvi.  The southern slope of the basin which were quite a busy place in the Classical to Hellenistic period appear to be used far less intensively in subsequent periods.  This seems to represent an overall contraction in the intensive activity areas of the city of Thisvi and parallels to a certain extent the results of the survey at Thespiai to the east. 

Unfortunately, the maps which appear above are incomplete.  I have not yet been able to plot several of the transects from the western most area of the survey (Area C in the map below).

While I think that there is a good chance that I'll be able to place these survey transects in the future (with the help of aerial photographs), at present the best I could do for the purpose of analysis is to compare the distribution of material in each of these sections to determine whether the distributional maps show a contraction of activity or simply a shift in the main area of activity from one part of the region to another.  These charts are based on the almost convincing assumption that the total sample of each area is roughly equivalent and thus the proportions of various types of material is roughly comparable.

A first glance it would appear that Area E and Area C produced substantial more post-ancient material than either Area A or Area D.  This is large due to two significant Late Roman sites in each of these areas.  In the case of area C, the significant concentration of Late Roman material at the beach at Vathy accounted for close to 7% of the overall percentage of Late Roman material from the area.  In Area E, the result was even more dramatic with a single site (E1) producing close to 20% of the Late Roman (and post-Classical material).  Eliminating these concentrations, however, produces a fairly even distribution of post-Classical material across the entire survey area ranging from 7% in Area A to just over 13% in Area E.  As a result, I feel comfortable stating that the distribution of what an earlier generation of survey archaeologists might call "off-site scatter" is relatively consistent across the entire survey area.  This is significant because at the site of Thespiai to the east, the survey team has argued that most of the material in the fields around Thespiai was deposited as the residents of the city spread manure (and broken bits of pottery discarded in trash piles) to fertilize crops.  Thus the distribution of "off-site material" could reflect the intensity of agricultural activity in the basin and the density of settlement at the central site of the survey area, Thisvi itself.

For more on this research:

Reclaiming Thisve Data
Thisve Basin, Archaeological Visualization, and Curating Digital Data
First Out: A First Draft of An Intro for New Views on Old Data
Survey Archaeology Finds as Data

Survey Archaeology Finds as Data

One the small arguments that I make in our paper on re-analyzing the survey finds from the Ohio Boeotia Project is that the changes in technology have influenced the way that data were recorded in archaeology. One thing that is particularly noticeable in the data is that little effort was made to normalize the finds data. This is not because the project was not imagining that their data could be analyzed quantitatively. In fact, the density or distributional data was collected on paper forms that were suitable for direct entry into a spreadsheet type program.

OBE Field Recording Sheet

The finds data on the other hand was collected in a way suitable for a text type catalog. Such catalogues have been a standard part of archaeological documentation for a century. They are typically include measurements for the object and then a textual description of the fabric, shape, decoration, and date of the object with some notes on comparanda. Such thorough textual descriptions of objects is useful for establishing the identity of fossil types in an excavation context. In other words, these objects serve to date stratigraphic layers in excavation and describing them accurate is important for establishing the validity of the identification of the object.

With the introduction of "New Archaeology" (or processural archaeology) in the early 1960s, there emerged a greater interest in quantification and quantitative methods for documenting past human activities. The tools to perform these kinds of quantitative analysis, however, were expensive and time consuming (often involving processing punch cards, expensive mainframe computer time, or even tedious and error prone hand calculations). The increasing availability of personal computers in the first years of the 1980s paralleled the development of important software packages for organizing data on desktop computers. IBM's iconic DB2 came out in 1983 as represented the first SQL driven desktop database. The same year saw the introduction of a powerful new version of the longstanding statistics package SPSS (SPSS-X). Moreover, the portability of both hardware and software made it possible to enter data in the field. This undoubtedly shed light on the practice of data collection in direct contact with data entry (if not on the fly analysis). The desktop computer, SQL driven database software, and new statistics packages put complex statistically driven archaeological research in the hands of even the smallest intensive survey project.

Apple Computer Advertisement from 1985

The Ohio Boeotia Expedition worked on the cusp of these significant changes concluding in 1982. As a result, they collected quantitative data on artifact densities (which could be easily calculated by hand), but did not collect the finds data in rigorously normalized way. This is not to say that the data was not collected systematically. In fact, the systematic and robust collection of finds data has made it possible to normalize significant parts of the finds notebooks. The results can then be projected across the transects that were remapped into our GIS.

Classical Period Finds

Hellenistic Period Finds

Late Roman Period Finds

With time and creativity these data could be translated into chronotype data. The chronotype system is the systematic recording system that we used to document finds from the Eastern Korinthia Archaeological Survey and in the Pyla-Koutsopetria Archaeological Project (as well as several other significant survey projects). We are gradually translating the context pottery from the Ohio State Excavations at Isthmia into this same system. This will create a foundation for some kinds of cross project analysis. At the same time, it will not eliminate the need for careful catalogue entries. The practice of recording careful descriptions of artifacts central to chronological and functional arguments will continue to remain central to archaeological documentation. In fact, the improved ability of desktop database software and "natural language" search engines will make these descriptions increasingly susceptible to the same kind of quantitative analysis as more standardized (and in most cases abbreviated) forms of notation.

First Out: A First Draft of An Intro for New Views on Old Data

To provide some context, this is a first draft of my introduction to a paper that Tim Gregory and I will present at this winter's Archaeological Institute of America's Annual Meeting. The paper deals with survey data produced by the Ohio Boeotia Project in the Thisvi Basin in Boeotia. You can read more on our work to re-habilitate and re-analyze this data here. The paper will be in a session called "First Out: Late Levels at Early Sites".

For our paper, I plan to tweak the meaning of first out a bit. To begin, the surface assemblage, no matter what the chronological range of the pottery present, is always first out. The systematic documentation of surface assemblages provides a means to apprehend the over all site formation process in which the surface of the ground will invariably the most recent events in the history of the site. First out, in terms of survey, data represents the boundary between the work of the archaeologist and the layer formed by "archaeological processes".

For the survey data gathered over the course of the Ohio Boeotia Project from the Thisvi Basin, first out has another meaning as well. The OBE was among the earliest "siteless" style intensive surveys typically associated with the Second Wave of intensive survey in Greece. These projects sought to document systematically the distribution of ceramics across the landscape rather than simply focusing on individual sites. The focus on the distribution of artifacts both "on site" and "off site" produced more robust and complex datasets that pushed the limits of quantitative and GIS technology of the day. The tools that we have now, on desktop computers, provide us with new ways of analyzing the data from these early siteless projects. More importantly, however, these projects capture a layer of an ephemeral landscape. Survey archaeologists have come to realize that the landscape documented by intensive pedestrian survey represents a distinct moment in the history of the surface of the ground. Changes in erosion patters, surface visibility, and cultivation practices significantly influence recovery rates which, in turn, affect the chronological character of the assemblage produced. In a bigger picture sense, the continued development of the Greek countryside (particularly in areas with easy access to the coast like the Thisvi basin) further endangers surface assemblages. Since the overall distribution of material across an area rarely warrants the status of "site", there are few protections in place to prevent the destruction of surface scatters which preserve evidence for both subsurface activity as well as more "low intensity" uses of the ancient and modern countryside.

It's important to recognize that our efforts to re-analyze the survey data from the Thisvi basin is a key step in preserving the results of an effort to document the disappearing landscape. These efforts run counter to the highly-critical stream in the methodological discourse associated with intensive survey which tends to see the results of earlier field work to be methodological unsophisticated, problematic, and potentially misleading. Each new survey purports to make significant contributions both to the survey method and the more general body of archaeological knowledge. The drive to innovate has had produced ever more robust datasets, but has also led to a relative neglect of earlier work. This in turn, has made the task of curating "early" siteless survey data less appealing: despite its potential for capturing disappearing or ephemeral landscapes, it is seen as being too methodologically problematic to reward the efforts of re-analysis.

Finally, we can address first out in the way meant by the organizers of this panel. Perhaps no area has seen greater advances through the work of siteless survey than later periods. The growth of intensive survey coincided, roughly, with John Hayes' landmark works on the chronology of Late Roman ceramics. At the same time, survey archaeology has become an important tool for documenting less visible periods at traditional sites including the Byzantine, Medieval, and Ottoman periods in Greece. Shifts in settlement pattern and the continued privileging of the antiquity in both the historical and archaeological discourse of Greece has made the work of survey archaeology in documenting post-antique levels particularly valuable.

That's my first draft of an introduction. Stay tuned for more on this project over this week as I get to writing up the analysis of the survey data...

Thisve Basin, Archaeological Visualization, and Curating Digital Data

For the past couple of weeks, I've been working on preparing the data from the Ohio Boeotia Expedition (1979-1982) for re-analysis.  This is all working toward presenting an expanded interpretation of the results from this field work at a panel put together by Kostis Kourelis and Sharon Gerstel at the 2010 Archaeological Institute of American Annual Meeting.  The panel is called "First Out: Late Levels at Early Sites".  The site of Thisve is primarily known for its relatively well preserved Hellenistic fortification wall and substantial corpus of published Greek inscriptions.  My paper will focus on the surface remains from across the broader region with particular attention to Late Roman and later material (although the surface assemblage no matter how you excavate, is the first out.)

As of this weekend, I finished keying all the density data from the survey transects that can be reasonably mapped.  There were three or four transects which I've not been able to map in accurately in the GIS.  Despite this missing data, I think that the mapped transects reveal something about the distribution of ceramics across the plain south of the ancient city of Thisve (and the modern villages of Thisvi and Doubrovna). 

One of the interesting things is that this was not the first time that this data was mapped.  Three maps of the archaeological "topography" of Thisve appeared in T. Gregory, "Archaeological Explorations in the Thisbe Basin" in the Boeotia Antiqua II: Papers on Recent Work in Boiotian Archaeology and Epigraphy (Amsterdam 1992), pp. 17-34.  The OBE team plotted these maps using Surface II software against a digitized map of the Thisve plain.  Unfortunately, from what I can gather, this original map of the basin no longer exists.  So I've had to reconstruct the location of the transects from the notebooks in which the data was originally recorded. 

The comparison of these two images and the processes that created them is a nice, small case study both for archaeological visualization and for the curation of digital media.  I think that my more recent map of artifact densities and transect presents a more accurate picture of the distribution of ceramics across the landscape.  That being said, even my plan has generalized.  The samples from most of the individual survey units, mapped as squares in my plan, were taken from a 1 m sq area.  I've extrapolated them across the entire unit (i.e. the width of the transect x the sampling interval).  The lower images, generated by Surface II plotting, have simply extrapolated the density of artifacts across the entire Thisvi plain.  I suspect that the linear arrangement of survey units (an early form of the Sydney Cyprus Survey Project's "Souvlaki method" of surveying the landscape) exposed the distribution plots to various kinds of "edge effects" as the software was asked to extrapolate artifact densities farther and farther from known or established data points.  Moreover, the jagged abstraction of these figures makes it difficult to assign the surface densities to real space on the map (note the lack of scale or even a north arrow on figure 3.6!).

The disappearance of the Surface II data is another important issue.  While it is easy to criticize a project for failing to responsibly curate their data, in fact, the field notes books and survey sheets from the project are well-maintained and organized.  The maintenance of data produced over the course of secondary analysis is a challenge for a small project like the OBE which worked in the area for only three years and published their analysis and then dispersed.  Survey projects, in particular, suffer from rather ephemeral constitutions (as opposed to the usually more permanent relationship between excavators and a particular site).  If the relatively low impact of survey archaeology on the landscape tends to attenuate the link between the archaeologist and a particular place, then the combination of paper and high tech applications ranging from relational databases to GIS mapping applications adds a layer of complexity to curating the digital data that these projects produced.  In most cases, data was (and I'd argue still is) collected from the field in paper form and then keyed and plotted into digital databases of various descriptions.  So the digital data represents the first phase of analysis rather than a primary data collection.  Perhaps this is part of the reason for failing to maintain the digital data as carefully as the paper forms and notebooks.  In recent years, a more serious approach to the practices involved in curating digital data (and survey data more generally) will undoubtedly change future practices.  Hopefully our work with the data from Thisvi will represent an important case study for the curation of digital data in the context of re-analysis.

Some New Work on Historic Corinthian Lithics

The most recent volume of Hesperia also has a nice article by my favorite stone tool expert, P. Nick Kardulias.  Nick is a long-time colleague from Ohio State Excavations at Isthmia (and the Eastern Korinthia Archaeological Survey) and is publishing our lithics from the Pyla-Koutsopetria Archaeological Project.   His article, "Flaked Stone from Isthmia" emphasizes (in particular) flaked stone from post-prehistoric contexts at Isthmia.  He also includes a brief discussion of lithics found in the Kromna excavations and associated with some other areas in the Eastern Corinthia surveyed by the Eastern Korinthia Archaeological Survey.  Nick makes the useful and interesting point that lithic technologies persisted into the historic period (following on his and others important work along similar lines in the Southern Argolid and in the study of doukani (or threshing floor) blades on Cyprus).

Nick's arguments for the use of lithics into the historical period is important for survey archaeologists.  EKAS found hundreds (if not thousands) of chert and obsidian objects over the course of its intensive survey in the general vicinity of Isthmia.  He makes some off hand observations regarding the cautious tendency for survey archaeologists to assign lithic artifacts prehistoric dates (pp. 333-336) especially when they appear in multiperiod sites.  The result of this caution is that we may be underestimating the number of lithic artifact datable to the historic period.  There is reason to think that the large assemblage of material from EKAS (which I think Nick is studying) may provide some evidence for the use of lithics in historical periods.  Of the 222 units which produced obsidian or chert objects, only 95 of them (43%!) produced clearly datable perhistoric pottery.  While the problems with recovering and identifying prehistoric pottery in a survey context are well known and my hasty analysis is a simply count of units (rather than a more useful analysis of their spatial distribution across the site (i.e. it may be plausible to argue for the prehistoric date of lithics found in units adjacent to those with prehistoric pottery), it nevertheless suggests that a careful study of the distribution of lithic artifacts across the survey area might lead to some suggestive observations.  (I'll try to do a spatial analysis of this data sometime over the weekend...)

Nick Kardulias looking at one big lithic in Lakka Skoutara

One of the more interesting things about the historic use of lithics is that obsidian (and maybe chert) blades could be reused long after their original production.  This is interesting because Kardulias argues that the initial energy needed to produce lithic blades and other tools was not excessive nor did it require a particularly high level of expertise.  Moreover there were good chert sources throughout the Isthmia plain most notably on Acrocorinth.  This is all to ask why would people re-use lithics in the historic period (other than shear convenience or some accident of survival) if they are relatively easy to acquire and manufacture?   

Landscape(s) of Time

One of the goals of our paper for the Modern Greek Studies Association meeting was to experiment some with the notion of landscape. We juxtapose four different ways of thinking about the place called Lakka Skoutara. By contrasting various methods for documenting Lakka Skoutara -- ranging from intensive pedestrian survey to formation process archaeology and oral history -- we sought to problematize the link between method and place in the Greek countryside. In particular, we focused on how different methods and perspectives produced meaning on different chronological scales and appealed in the conclusion to folks like Braudel and his fellow Annalistes who sought to document history with a similar sensitivity to scale.

One issue that I am struggling with is whether to consider the notion of landscape as the space that encompasses all possible methods, interpretations, time scales, and meanings. Or, on the other hand, whether methods, interpretations, and time produce different landscapes which can be juxtaposed and compared as discrete entities. If the former, the landscape becomes a place where different regimes of knowledge interact. The physical reality of place becomes the common ground for these different ways of understanding our environment and history. Landscape archaeology represents the study of the landscape as a place where different ways of understanding the lived environment interact and overlap.

If it is the latter, we allow for the physical place of archaeological work to dissolve or even collapse into notions of landscape that vary as much physically as methodologically. Thus landscapes have different physical, experiential, and epistemological realities that have little common ground. In this assessment landscape archaeology becomes the work of documenting the various landscapes present (as much as this is possible) and creating the conditions necessary for them to share the space of the archaeological document.   

This may just represent a tiny crisis in terminology, but it may also represent something larger. The way that I am thinking about it, the former appraisal of landscape makes it possible for individuals to comprehend and live in a landscape that relies upon various discrete disciplines, methods, regimes, and experiences to create meaning. If the latter, I wonder if the idea of landscape becomes so highly individualized that they can only intersect within the realm of archaeological documents (both in the sense of real, dirty-nails, archaeology as well as the more Foucauldian variety).

Between Sea and Mountain: The Archaeology of a 20th Century "small world" in the upland basin of the southeastern Korinthia

This weekend, David Pettegrew and I are off to Vancouver, BC to give a paper at the Modern Greek Studies Association conference.  Our paper will focus on our work with Tim Gregory and Lita Tzortzopoulou-Gregory at the upland basin of Lakka Skoutara in the southeastern Korinthia.  While we have been preparing a proper empirical study with lots of mico-historical detail for a formal archaeological report, David and I decided to take a bit more of a methodological approach to the paper at the MGSA meeting.

We focused on four scales of analysis at the site produced by the various methods that we used to document the material evidence present at Lakka Skoutara.  We used diachronic intensive pedestrian survey to document long term changes at the settlement.

We placed the results of this survey work in a broader regional and national context to demonstrate how this material is the evidence for a dynamic set of interconnected local, regional, and national economic and political processes. 

We also returned to the site every other year for a decade and documented the changes to individual buildings at the site.  Most of the buildings at Lakka Skoutara are abandoned or only kept up in a very superficial way, so documenting their deterioration or curation allows us to understand the processes that produced the archaeological landscape documented through intensive survey. 

Finally, our team collected oral history interviews from people who used the Lakka in various ways.  These interviews allowed us to put formation processes within a social context.

The goal of this approach is not to attempt to reconcile the interpretations or analysis produced by various methods, but rather to produce parallel narratives that are linked through their common reference to the landscape.  The interplay of these references to the landscape (i.e. signifiers) is not meant to compile a "total history" of the landscape but to capture the dynamic nature of the landscape as a product of experience and methods.

The key to this approach is recognizing the modern period as an important lens for viewing the landscape.  An older generation of archaeologists often tended to ignore the modern landscape as they sought to reconstruct the ancient one particularly for rural areas.  One result of this approach was an understanding of the Greek countryside, both in antiquity and in modern times, as a static place.  More recent work on the Greek landscape, however, has emphasized the dynamism of the 19th and 20th century Greek countryside.  Using finer resolution documentary sources than are available to scholars of antiquity and observing more carefully the living archaeology of Greek village life, archaeologists of modern Greece have managed to uncover a vitality in the countryside that less critical observers missed.  By ascribing this reality as much to a method uniquely applicable to the modern period (that is, interviews, easy examination of a whole range of ongoing formation processes, documentary evidence) as to the dynamic nature of the modern Greek landscape in particular, we argue that the archaeology of modern Greek landscape emerges as a vital interpretative lens for reconsidering ancient landscapes.  This isn't to simply turn the traditional method for understanding landscapes on its head (or resort to a clumsy ethnoarchaeology) and argue that ancient landscape are similar as the modern landscape but for our ability to document the processes that created them.  Instead, incorporating the modern landscape into our analysis of landscape more generally allows us to problematize the methods used to create archaeological landscapes and show that the idea of landscape requires reading methods across periods.  Thus the landscape becomes a product of our knowledge as archaeologists and the tools that we have at our disposal to document the material culture present for any period. 

Hopefully we'll have a draft of the paper posted by the weekend. 

For more on our work at Lakka Skoutara see these posts:

Slopes and Terraces at Lakka Skoutara
Corinthian Infiltration: The Interior of Some Houses at Lakka Skoutara
Lakka Skoutara: The Survey
The Houses of Lakka Skoutara
Collapse
Provisional Discard
Construction in the Corinthia

Preliminary Analysis of Pyla-Koustopetria Archaeological Data or Thinking Out Loud 3

Last week, I looked at surface visibility and artifact densities.  This week, I want to look at two issues when considering the analysis of distributional data across the Pyla-Koustopetria Archaeological Project's study area.

First, the distribution of ceramic material and the topography of our site recommend that we divide our site into zones for analysis.  I decided to divide the survey area into zones to attempt to isolate some variables influencing the distribution of material across the site.  In particular, these zones capture areas with distinct patterns and levels of artifacts.  Zone 1 -- the area around Koutsopetria -- has a ceramic density of over 4000 artifacts per hectare.  Zone 2 -- the coastal plain to the east of Koutsopetria -- has an overall artifact density of barely 700 artifacts per hectare.  Beyond that the areas capture very different environmental conditions.  Zone 1 consists largely of grain stubble fields with an average visibility of around 48%; Zone 2 units are usually sandier soils only a few of which are under cultivation.  The average density in Zone 2 is over 70%.  Zones 3 and 4 are defined as much by topography as by artifact densities.  Zone 3 centers on the prehistoric site of Kokkinokremos and featured units shaped to take into account the plowed top and unplowed slopes of this.  Zone 4 is the top of the Kazama ridge which extended north from the height of Vigla.  I have isolate Vigla from any zone since the densities there were so high and the environmental conditions in that hill were distinct. 

Despite the fact that these zones are the creation the archaeologist and archaeological methods, they nevertheless provide a way to limit some of the known variables (significant variations in artifact density, for example, or clear differences in land use or environmental conditions) in order to isolate other variables which may have had locally significant influences on the distribution of artifacts.  Of course, this assumes that the characteristics that formed the basis for the zones are not the main factors on our ability to map ceramics across the survey area.

To test that I isolated a number of variables that we have seen influencing our ability to document the material on the surface and look at whether they coincided with the zone divisions.

First, I mapped the distribution of grain stubble fields across the site.  Grain stubble can be the survey archaeologist's worst nightmare as it typically accompanies the remains of cute wheat which can obscure the surface of the ground almost entirely.  The darker units had grain stubble.

In units without grain stubble there was frequently some standing vegetation.  We recorded the height of standing vegetation across the entire survey area.  The darker the color the higher the vegetation.  Note that the height of the vegetation doesn't influence visibility in a predictable way.  Sometimes waist height vegetation actually makes the surface easier to see.

Another factor that plays into the distribution of ceramics is whether the fields show signs of recent plowing.  The plow often bring material to the surface from deeper with the plow-zone, but it can introduce background disturbance (see below) and break pottery into small fragments that increase the number of artifacts without increasing the amount of material (say, by weight) in the unit.  At the same time, it tends to limit vegetation across the area.  The darker areas are plowed fields.

I also mapped background disturbance across the zones.  Background disturbance is a survey archaeology term that describes the amount of non-archaeological material in the surface soil that confuses the eye of the archaeologist.  The most common form of background disturbance are fragments of bedrock chipped by the plow and turned into the soil.  This material often looks like pottery and makes identifying ceramic material in the soil more difficult.  Some analyses of the data from the Eastern Korinthia Archaeological Survey has suggested that background disturbance often influenced the ability of fieldwalkers to document material on the ground to a considerable degree.  The darker the color the more background disturbance there was recorded.  Note the consistent moderate to heavy background disturbance across Zone 4.

These basic environmental characteristics can now be compared to artifact distribution both across the site and in the individual zones.  Stay tuned for more!

For more Thinking Out Loud see:

Preliminary Analysis of Pyla-Koustopetria Archaeological Data or Thinking Out Loud
Preliminary Analysis of Pyla-Koustopetria Archaeological Data or Thinking Out Loud 2

Preliminary Analysis of Pyla-Koustopetria Archaeological Data or Thinking Out Loud 2

I am continuing to work on analyzing the survey data collected from 4 seasons of intensive survey at Pyla-Koutsopetria in Cyprus.  On Monday, I did focused on the relationship between artifact density data and surface visibility.  The survey area for PKAP was particularly uniform in ground cover and field conditions.  Most of the survey units had been under cultivation with cereals and were covered with grain stubble or were recently fallow. 

Average visibility across the entire survey area was around 60%. 

Average density of ceramic objects per area walked across the entire site is 2183 ceramic artifacts per hectare.

One of the key discussions in the analysis of surface density data is how to compensate for variable visibility.  Our survey area consisted of only 471 units -- hardly a robust sample.  The highest density areas of the site coincided with units of middling visibility and (to make matters worse) there were a significant number of very high visibility units that produced almost no artifacts (predominantly from an area that was an infilled ancient embayment and a coastal marsh drained in relatively recent times).  So, the small sample size and these topographical and archaeological patterns make doing any analysis of artifact density and surface visibility across the entire site difficult.

I did, however, run a small analysis on the artifact densities and visibilities from the area of the Koutsopetria plain.  We have reason to think that the distribution of ceramics across this area could be relatively uniform as most of these fields overlay buildings from the Late Roman period (if not other periods as well).  At the same time, the units had some variation in visibility with the lowest visibility units being 20% and highest visibility units being around 60%. Most units had 30%-50% visibility.  While the sample size is disturbingly small, it is interesting that there is a nice linear relationship between artifact densities and the surface visibility in Koutsopetria with an R-squared of 0.9229.

This does not hold up across the entire survey area where for the same range of surface visibility there is no evidence of a linear relationship at all and the R-squared is a laughable 0.5475.  (Note that since the following graph compares units of different sizes, I compared them using density per area walked (per ha).  The graph above compares units of identical size, so I can compare raw ceramic counts.)

 

For more installments of Preliminary Analysis of Pyla-Koustopetria Archaeological Data or Thinking Out Loud:

Preliminary Analysis of Pyla-Koustopetria Archaeological Data or Thinking Out Loud

More as I continue to work through the data.

Lakka Skoutara: The Survey

I've already blogged a bit about my collaboration with Tim Gregory, David Pettegrew, and Lita Tzortzopoulou-Gregory in documenting the abandoned rural settlement of Lakka Skoutara (The Houses of Lakka Skoutara, Collapse, Provisional Discard, Construction in the Corinthia).  We conducted an intensive survey in this upland basin in 2002 and I've just begun to analyze the distribution pattern of material across the landscape there.  Since we only had about a week to do our survey at the site, we decided to sample the various parts of the basin so that we would capture the hillslopes, slope wash, the bottom of the basin and areas across the entire basin for east to west including fields in the immediate vicinity of the abandoned houses that David Pettegrew and I have so carefully documented.  In hindsight, I wish we had surveyed the entire area since the results of our survey were so interesting.

Daniel Pullen and Timothy Gregory read the ceramics from the site and the entire Eastern Korinthia Archaeological Survey helped out with the fieldwork.  The basin produced material from the Final Neolithic (ca. 3300-2500 B.C.) to the modern period with noticeable concentrations of material in the Roman, Medieval, and Early Modern periods.  In the maps below each dot represents a single artifact. 

The dates assigned to the various maps derive from the Chronotype dates and reflect the specificity with which our ceramicists could identify the individual artifacts.  The modern houses are represented by little dots and the larger black dots are threshing floors (alonia). The coloring of the survey units represents the total density of material present in each unit.

Final Neolithic

 
Final Neolithic to Early Helladic I

 
Early Bronze Age

Early Helladic I

Early Helladic II

Late Bronze Age

 

Archaic Period

Archaic to Classical

 
Archaic to Hellenistic

 
Early Roman

Roman

 
Late Roman

Roman to Medieval

 
Medieval

Late Medieval

Early Modern

Modern

 
Very Recent

It's clear, for example, that the prehistoric material clusters in a very different place than the highest density of ancient material (particularly the Roman material).  In contrast, the "Greek" period material and Roman period material cluster to the northeast of house 4.  Later, the Roman and Medieval material seems to concentrate in some of the same areas, particularly the units to the east of house 9.  These clusters of material suggesting some local continuity in occupation or activity.  For the material to cluster so relatively clearly in a small survey area was welcome and rather unexpected.  It will certainly make my job of writing up the distributional data from the survey easier.

Check back soon (maybe not today, though!) for more on Lakka Skoutara over the coming weeks.