Blog

The aftermath

It feels like the last two weeks of field work flew by -we were that busy. Following the excitement in Tract 45, we continued surveying Sectors F, E and I in the southern plateau. Having completed that part of the survey footprint, our teams split. Team blue circumnavigated the citadel to investigate the tracts along the southern, eastern and northern slopes in Sector B.Team orange launched an exploration of Sectors G and I to east and southeast of the citadel beyond the chapel of Agioi Saranta. Eventually the teams joined forces to complete Sector I, which wraps around Asprovouno to the east, and sample Sector H tracts closest to the citadel road. The latter was a lesser priority, as it had been an afterthought in the planning process, but we felt it necessary to explore at least the part where Curtius and Kaupert had noted a well-preserved building in the late 19th c. The decision to look in that area would prove very worthwhile and one of the highlights of the 2019 season (see below).

While Sectors B, E and F were fruitful, especially the latter two areas, Sector I looked less and less promising as we headed to the east. We noticed a major change in soil composition to match, from the rich red clayey soils of Sectors E and F to thin, white chalky soils emanating from erosive processes at Asprovouno (aptly dubbed then ‘the white mountain’). Whether the absence of finds, nearly complete at times, east of Asprovouno was to do with erosion or the lack of habitation remains an open question for the geomorphology study. Erosion, manifested in the form of deep runoffs on the slopes of Sector B, certainly appeared to be a factor in the reduced densities of finds along the west slopes of the citadel as well.

Following a few days of unproductive walking in the eastern part of the survey, however, we were rewarded by the discovery of a major site on the last hour of the last day of field operations (of course it had to be on the last day). Unsurprisingly, the site, associated with a large quantity of roofs tiles (some of which nearly intact), bricks and large quantities pottery, was situated immediately to the south of one of Curtius and Kaupert’s buildings. The building itself, however, was not seen and does not appear to have survived (although we shall return with geophysics). In the days prior we had also noted several more new sites in Sectors C, E and F, including a likely Classical site associated with much excavation-grade pottery recently exposed due to torrential rains. A further site was tentatively identified north of the citadel- this will be investigated more fully in 2020. In the meanwhile, we were briefly visited by John Bintliff, who offered great advice and ideas for the future.

The last few days of the 2019 season were dedicated to museum work: cleansing remaining finds from the last week of field work, storing them safely, and recording and photographing pottery and other diagnostic finds for the purposes of season reporting. Altogether we collected over 16,000 sherds dating from prehistory through the early modern era, and hundreds of stone, terracotta, metal and glass objects. We were able to ascertain local ceramic production, through waster sherds, kiln stands and other tell-tale finds. Excitingly, we also produced evidence on local metallurgy (iron), attested in the form of slag from several areas of the survey.

Both Steve and Anastasia were impressed by and grateful for our team members. All students were just delightful to be with. They meshed together well despite pressures of field work, were mature beyond their years and brought along a unique mixture of excellent work ethic, congeniality and diverse outlooks in life. Likewise, Aris, Michalis, Katerina and Eleni at the museum, under Eleni Andrikou’s leadership, were the best colleagues we could have possibly asked for, participating in the field work, ironing out operational kinks, working with us to configure space efficiently and even staying overtime to extend museum hours.

We look forward to sharing the results of the 2019 season with the public, starting with the Aerial Archaeology Research Group Annual Conference and the Annual Meeting of the Archaeological Institute of America. The WebGIS has been updated with new layers reflecting the 2019 season activities. Stay tuned and watch this space for the 2019 report.

Sector A and a first taste of Sector F

Following the main team’s arrival on July 6, we started on Monday with sector A to the southwest of Lake Marathon. The heat wave made things rather difficult the first few days, but we acclimatized and proceeded to collecting sector A to completion by Thursday. Pottery finds there were present but not abundant. We confirmed the likely location of the Middle Bronze Age tumulus, but the finds did suggest later habitation in this area as well. On Friday we jumped onto Sector F on the other side of the lake. There, following a storm the preceding day, we were met by the perfect conditions: freshly plowed fields, a rained on/exposed surface, and an area with known archaeology from the Curtius and Kaupert topo map (Karten von Attika). As a result we collected much pottery starting early in and throughout the day. Stone blocks, some of which finely cut, were also identified, recorded and geolocated.

Systems-wise, Sector A with easy access and generally excellent conditions gave us the opportunity to hone our process and the ESRI Collector-Survey123 integration before tackling more difficult terrain near the citadel. While the offline web map and associated survey forms (tracts, transects, architecture, daylog) all worked as expected, we needed to tweak our transect recording process to enable more flexibility in capturing actual field conditions. The pre-made polyline layer where transects were coded was not used much. Instead we opted to navigate the fields using the tracts layer in the web map and use the transects forms directly for data input. Once at home, we synced all data in the cloud, recorded new transects walked daily and inserted these in the GIS manually. We also processed the images taken in the field and stored in the dedicated Google drive associated with our tablets. The architecture form will be improved this week to allow integrated capture of geopoints.

The team blue and orange tablets syncing transect data to the cloud on wifi after the daily field work

Tania Yangaki skyped in on Thursday to give a brief intro on Byzantine pottery and, after returning from the field on Friday, Kalliopi Sarri (with Soren Dietz) popped in at the museum to say hello and to give students a similar intro to earlier prehistoric (Neolithic-MBA) ceramics. Of course, we would be remiss to not spend some time at Oropos where we had a lovely dinner on the beach at dusk. Overall a very productive week.

Our favorite tract so far: T45. Waster sherd material included (kiln waste?)
Kalliopi (Popi) giving an intro to prehistoric pottery apres field work of the day
End of week dinner at Oropos/Skala

And so it begins

Our first season officially kicked off on June 26th with an early heat wave and the geoarchaeology group hitting the ground running (Tim Kinnaird, Neil McGlashan Rebecca Bateman and Anastasia Dakouri-Hild). We discussed research questions and priorities vis a vis the footprint of the 2019 season (as well as the tentative footprint for 2020), and having consulted a combination of layers (satellite imagery, LIDAR DEM, LIDAR-derived terrace features, the IGME-derived geology layer etc.), we spent a considerable amount of time surveying the broader landscape surrounding Kotroni by car and on foot, initially to gauge the accuracy of the IGME map from the 1970s, and also to familiarize ourselves with the rocks, soils and geomorphology of the area of interest.

The geo collection was also useful as a trial run for our born-digital data collection system, which consists of several AGOL layers downloaded for offline use on Samsung Active2 tablets equipped with ESRI’s Collector and Trimble’s R1 survey grade GPS units. The system performed well, giving a variety of geospatial information in the field, easy syncing, ample battery life and submeter (typically 80 cm but frequently 40-50 cm) horizontal accuracy in most settings with SBAS correction. The vertical accuracy was lesser, as expected from an antenna-less system, but since a LIDAR geotiff was available to us through our offline web app on the tablets, we did not have to rely on the vertical accuracy of the R1.

We created dedicated GIS layers to receive the new geology and geomorphology spatial data created in the field (geology polygon, polyline and point-based layers, plus image attachments). We also sampled geological (natural) terraces, formed by the river system in the area, and agricultural (manmade) terraces using portable OSL equipment. Tim was able to run the preliminary analyses within the hour using this equipment, which gave a tentative sense of the relative age of sampled terrace layers right in the field. Further analyses of collected samples will be undertaken at the CERSA Luminance Lab to clarify the dates of the associated deposits.

Through these investigations, we hope to get a better sense of whether the agricultural terraces surrounding the citadel are ancient, at least in part; to define geomorphological units and extent of manmade intervention in the landscape subject to intensive survey collection later on in the season (which will help refine the methodology and guide the interpretation of artifacts); to understand the geological characteristics of the landscape in question (including natural resources); and to clarify the geomorphological processes that have brought about the landscape in its current form.

We are are currently working on watershed/erosion/deposition models to use in conjuction with this new geomorphological/geological data. Such information will tint our understanding of visibility and recovery rates during the intensive survey.

A view from the citadel facing south.

Tim working his magic.