This week students at Marj Rabba learned about the wonderful worlds of lithics (stones) and pottery from two of our expert analysts. We had hands-on practicals in the afternoon after our long day in the field, yummy lunch, and siesta. Every day in the field we collect up all of the artifacts (broken pieces of pottery, animal bone, lithics (worked stone)). We find the artifacts in situ (that means in their original place/archaeological context) or we find them in the sieve. At Marj Rabba we are doing 100% sieve from all contexts except the very disturbed topsoil. Here Achmed and Amir are sieving the material from their excavated area:
We bring back the artifacts from the field and in the afternoon we record, wash, sort, and label them for the experts to analyze.
Washed pottery drying in a fruit flat.
Here Dina explains some of the intricacies of Chalcolithic . . .
Dina Shalem, PhD Haifa, is the leading expert on pottery from the Chalcolithic in the Galilee. She came by this week and gave us a tutorial on the types of wares, vessel shapes, and elements that go into studying pottery.
Below Yorke talks to the MR crew about lithics. Lithic analysis is the study of stone tools and other chipped stone artifacts using basic scientific techniques. At its most basic level, lithic analyses involve study of the artifact’s morphology, the measurement of various physical attributes, and examining other visible features (such as noting the presence or absence of cortex, for example).
Last season we began using aerial photography and photogrammetry to document excavation at Marj Rabba. We used a quadcoptor, an r/c plane, and a pole aerial photography rig to record images of the site at several altitudes. The pole was great for low level recording of features and individual squares, the quadcoptor was great for getting photos of the entire excavation area, and the plane was getting aerial photos of the entire area around the excavation. Our original plane, however, was only set up for carrying a GoPro Hero camera which takes great pictures but is not ideal for doing 3d photogrammetry because of its extremely wide angle lens. This set up gave us some good initial results and some excellent individual images of the site, like this:
This year we are using a larger model that has a better payload carrying capacity. It can fly longer, carry 2 cameras simultaneously, and is more robust:
Today we had the first successful flight of the season. The 2 camera setup means that we can get a nice video recording of what the landscape looks like from above while simultaneously recording vertical images that will be utilized for 3d modeling and mapping.
Here is a video of what the site looks like from onboard the plane:
As was discussed in the earlier post, the vertical still images provide the basis for 3d modeling. Here is a composite image (an ortho-mosaic) of the field system surrounding our site. This composite image is fairly low resolution, as it was constructed from a small subset of the total images to check how well the image recording went. However, this is a distortion free image and can be exported directly into our GIS map of the site. By doing a few more flights, processing the photographs more intensively, and combining them with data collected with our Total Station, we will be able to generate a complete high resolution composite image of the area as well as a high resolution digital elevation mode (DEM):
On Friday the Marj Rabba team took a field trip to Tel Akko.
Marj Rabba visits Tel Akko
We had a great tour courtesy of Prof. A. Killebrew of Penn State. Akko has served as a major trade center in the ancient world, with Bronze and Iron Age levels and appearing prominently in ancient Egyptian, Ugaritic, Assyrian, Classical, and biblical accounts. Prof Killebrew told us that locally Tel Akko is known as Napoleon’s Hill
It is famous as the city that withstood Napoleon’s two-month siege and marked the end of his campaign to conquer the Middle East.
Excavations at Tel Akko
Excavations on this ancient mound have uncovered remains of Canaanite, “Sea Peoples,” Phoenician, Persian, Greek, and Hellenistic culture.
We have several Unmanned Aerial Vehicles at the site. While they are primarily used to take vertical still images, they can sometimes be used to record videos of the site. Here is a short flyover of parts of areas CC and BB taken from our quadcoptor. This was recorded on a windy part of the day, so I did not fly particularly high or far, it just gives a brief glimpse of work at the site. The quadcoptor does not have any stabilization, so this video is somewhat unsteady:
Videos like this are of limited utility for anything other than recording pretty images of the site. What the UAVs are normally used for is to build 3d models of the site from sets of still images. These 3d models are powerful tools for research, mapping, and publication. They ALSO provide a way to see the site from above. Here is a quick, low resolution model of area CC, the same area that I was flying over in the video above. This is just a screen recording demonstrating how you can navigate around a 3d model in Photoscan (the software used to make these). After this stage, the 3d models will be geo-rectified and exported to arcGIS.
Today was day one of Marj Rabba, 2013. We started with a short tour of the site, to get our new crew members oriented. Short talks were given by all the directors and supervisors about various areas and features:
MK talking about the first season
YMR giving an overview of the main excavation area
The site looked a little beat up after sitting for a year, but this did not deter us, and we got to work clearing away vegetation, burst sandbags, and loose soil:
Cleaning up area BB
Here are aerial shots of the main excavation area from the quadcoptor, just after we got to work:
By the end of the day, the site was looking much better and ready for real excavation to begin tomorrow:
This season we have an array of participants from all over, representing no less than 12 home institutions. Joining us for the first time this year we have a group from Xavier University in Louisiana, ably led by Professor Michael Homan (http://michaelhoman.blogspot.com/) and his son Gilgamesh. Yo and Mo worked with Michael way back in the 1990s, when they were all younger, skinnier, and had more hair. I distinctly recall a painted blue D on a white belly …
After a very successful first foray into the Middle East, five more intrepid high school students from the Rowe Clark Math & Science Academy in Chicago, accompanied by the adventurous Maggie Culhane will join us for four weeks of fun in the sun.
This season at Marj Rabba we also have students and interns from: