zondag 27 maart 2011

Lost and found

Trench B, natural soil
After two weeks of excavation, we have reached the natural soil in the three trenches. Our fears were justified and it now appears that the occupation layers have been heavily disturbed by the agricultural activities of the late 20th century.
As often in tropical climate and especially on the top of a hill, the stratigraphy is very shallow. The monsoon rains wash the soil away and the anthropomorphic layers do not go much deeper than 30-40cm below the modern ground level.
The consequence for us is that the ancient occupation layers have been completely turned upside down when the area was ploughed. The material of 5 centuries of human activities has been mixed up in one thick (modern) layer. Fortunately, the material has not been moved over long distances, since pieces from a single ceramic are often found close to each other. Some areas are clearly richer in archaeological material than others. The top of the hill, where our trench A is located, has yielded very few ceramics in comparison with the two other trenches, in trench B traces of metal working activities have been detected. Among the lost and found in this thick disturbed layer, we have orange and blue beads, Chinese ceramics (mostly fragments of bowls and dishes), earthenware sherds (of jars, cooking pots, lids, kendis etc.), obsidian, Neolithic adzes, iron slag, brick fragments etc. 

Neolithic adze
 Glass bead

Below the disturbed layer, a good surprise was awaiting us though: traces of postholes (in trench A) and even the lower part of a post (in trench B). We finally have physical proof of the existence of a building on our hill! The coming week, we will extend the trenches and open new excavation areas in the hope of finding more post(hole)s.
Base of a wooden post

zaterdag 26 maart 2011

The antenna guy

Ben walking with the magnetometer
Johannes helping Ben with the GPR
Archaeology is not about digging anywhere. There are more and more ways to discover if there are archaeological features beneath our feet before excavation. And that is exactly the job of Benjamin, our Antenna Guy. His antenna is actually a magnetometer, an instrument that measures spatial variations in the strength of the magnetic field. The presence of iron, brick, burned soil and certain rocks causes anomalies in the Earth´s magnetic field and the magnetometer reacts strongly to these. The information is transformed into a grey-scale map that allows archaeologists to locate possible features. Unfortunately, it is not always easy to distinguish man-made features from natural phenomena. Besides, subtle features maybe hidden by highly magnetic materials.
Ben spends his days walking with his antenna or with his ground penetrating radar (GPR) between small red and white flags, recording the strength and velocity of the soil´s magnetic response. During this process, no one is allowed in the area: a belt buckle or even a paper clip would interfere and would be registered as anomalies by the magnetometer.
After one week of work, the results come out: the hill´s magnetic map is relatively homogenous, except for an area north of trench C, which shows a strong magnetic anomaly. The excavation does not yield any solid archaeological structure though. We nevertheless notice that the soil of the area contains numerous small metallic balls (about 1mm in diameter). Are they natural? Are they residues from metal working? Opinions are divided. We hope that the analysis of the samples will give us an answer. 

zaterdag 19 maart 2011

A day´s work

The excavation has started since one week now and everyone is getting used to the daily routine of the fieldwork. We wake up around 6.30, take a (cold) shower, a breakfast and get in the car. It is a 15 minutes drive to the foot of Bukit Gombak, then an 8 minutes climb to the top. The work starts at 8.00 and finishes at 16.00. With their hoes, the workers scrap the first centimeters of earth, while the archaeologists look for ceramics, observe, measure, fill the forms in, sort the finds and take pictures of the different excavation units (strata) .

Up to now, we have opened three trenches of 9m x 9m each, in order to explore three different areas: the top of the hill (trench A), the eastern slope (trench B) and 
the small plateau to the north (trench C). 
Jon, Feri, Soni, In, Samsiwar and Yarli in trench C
In trenches B and C, the material is abundant and diversified (pottery, Chinese ceramics, metal objects, obsidian), but trench A, contrary to what we expected, is poor in material. Besides, we have learned from our workers that the site used to be ploughed with a tractor until 5-6 years ago and we are wondering whether the archaeological layers are still in place or have been completely disturbed. In any case, we hope that the artifacts will give us a good idea of the duration and the type of occupation of the hill. A quick look at first the ceramics and metal artifacts seems to confirm our hypothesis, that Gunung Gombak was indeed a settlement site as early as the 14th. Some of the objects that we have recovered are clearly of a more recent date though, such as a VOC coin found in trench C. We still hope to find more tangible traces of a building, but so far nothing.
Pottery sherds found in two hours in trench C

zondag 13 maart 2011

Burning point

Smiling Kilian in front
of one of the landmarks

Slowly but surely, problems are being solved. Dominik has all the necessary authorizations and the Total Station has no secrets for Annika, Johannes and Kilian anymore. The preparation work may begin.

Andrison, a topographer from the local Institute for preservation of cultural heritage (BP3) walks through the high grass and keeps running up and down, taking measurements for the topographical map. Meanwhile, our Total Station team has chosen a series of landmarks that will help us to localize the trenches and the finds.

Two workers have started cleaning the site in the traditional way, cutting the grass and burning the ground.  A thick smoke now covers Bukit Gombak, and though the place has become less bucolic, some of us seems to find pleasure in playing with fire.

Marking the first trench

But the most moving moment of the day is undoubtedly the delimitation of the first trench, at the top of the hill. In a few days, the whole hill will be cleared, the three trenches will be marked and the real work will begin. Everyone anxiously awaits the digging. Some team members even let their imagination go. For Johannes and VĂ©ronique, it will be a wooden palace with few ceramics and a  couple of Changsha bowls (imported from China, they are easy to identify and excellent chronological markers for the 9th century). For Sekar and Annika, it will be an inscription, even a short one (to make Arlo forget that they are not ready with their essays yet?). Will our craziest dreams come true? We'll soon know.

Atop the smoky hill

Sekar keeps smiling

Annika and Baskoro playing with fire

dinsdag 8 maart 2011


Our base camp
Welcome on the website of the Tanah Datar archaeological project!
Thanks to Indiana Jones, archaeologists have earned a reputation of adventurers and treasure seekers. However, very few archaeologists fit this profile - and none of us does. So, forget about Hollywood and learn about the every day life on our excavation.
It all started a couple of years ago, when Dominik and Mai-lin got the idea of excavating at the top of the Gombak Hill, near Batusangkar, in the province of West Sumatra. The landscape was beautiful, the food delicious and the site promising. A few sherds and a fourteenth century inscription convinced them that going through the lengthy process of searching for subsidies was worthwhile. For most of us, however, the adventure really began on Saturday, when we left Jakarta and embarked on a plane to Padang.
Bukit Gombak before the excavation
From Padang, a three hour drive brings us to our base camp in Tanah Datar, where we are introduced to our hosts and settle in our new house. The house actually looks more like a four star hotel than like the usual excavation house. Instead of a dormitory we find spacious rooms for two or three persons. Our first visit to the site leaves us an excellent impression. The hill is covered with grass. It is a sunny, airy place with a few trees and a magnificient view on the surrounding plain and on the Merapi mountain.
Monday, Dominik must make sure that we have all the necessary authorizations - from the local governor to the owner of the land that we want to excavate. First disappointment. One letter is missing and we are not allowed to start the excavation. Annika, Kilian and Johannes, who went back to Bukit Gombak, try to install our brand new total station - it is supposed to give us the position of any structure on the site. In vain. 
Hopefully, tomorrow is another day.
Johannes et Kilian trying to install the station