Monitoring 1,000-year-old graves in Stavanger

Environmental monitoring in Stavanger is about 1,000-year-old skulls, skeletons and bone remains. The client is the Museum of Archaeology (UiS). The task is to secure cultural layers from the Middle Ages in Stavanger. 

A research project is underway close to the outer walls of Stavanger Cathedral. Behind the project is the Museum of Archaeology (UiS), an interdisciplinary university museum that researches the long lines between past, present and future. UiS is collaborating with NIKU on the project.

- "We want to find out more about Stavanger's former inhabitants," says researcher Hege Ingjerd Hollund at the Museum of Archaeology. She is leading the interdisciplinary research project funded by the Research Council of Norway.

Cautus Geo established the instrumentation in May this year. Cautus Geo has also established automatic and continuous monitoring inside Stavanger Cathedral. This happened during the restoration of the church. A network of sensors sends continuously updated data to Cautus Web.

- The sensors will detect any changes and alert us via Cautus Web if conditions change," says Jørgen Engebretsen, environmental geologist at Cautus Geo.

The country's oldest

Monitoring graves from the Middle Ages

Stavanger Cathedral is the country's oldest standing medieval church. It dates from the 12th century and was the episcopal seat from 1125. In 2025, it will celebrate its 900th anniversary, when the church will once again shine, after being under renovation since May 2020.

Archaeological excavations and surveys are also being carried out during the rehabilitation. The last time this happened was in 1967. Now new discoveries are coming to light. Under the church floor, burial chambers were found. They have been excavated and instrumented to monitor preservation conditions in the future.

- Outside the church, which is a separate research project, we will also monitor the preservation conditions in the cultural layers from the Middle Ages," says Hollund.

DNA testing

In the excavation area close to the outer walls of the church, skeletons and bone remains were found.

- Not surprising. In the Middle Ages there was a cemetery. Today you don't see any traces of it, but skeletal remains in old cemeteries are as expected," says NIKU's Vibeke Vandrup Martens. She is one of the researchers in the project and is also responsible for the project at NIKU (Norwegian Institute for Cultural Heritage Research).

- NIKU is also helping us to interpret and understand the environmental monitoring that Cautus Geo has established. "We're now going to carry out further research on the bone remains we've found in the excavation. If DNA is preserved in skeletal and bone remains, we have a good starting point for being able to say something about health, where they came from and other exciting things that can give us more knowledge about conditions in Stavanger in the Middle Ages," says Hollund.

5 years of data

- The monitoring has just started. It will continue for five years. "We need knowledge about the conservation conditions and the stability of the conservation conditions," says Vandrup Martens.

- NIKU has good expertise in environmental monitoring and provides good support and assistance," says Hollund.

NIKU has a framework agreement with Cowi and Cautus Geo for environmental monitoring of cultural layers from the Middle Ages and has established monitoring in a number of places in the country. Now also the old graves at Stavanger Cathedral.

- "We will consider possible extensions of the monitoring programme along the way. Firstly, we need to secure a longer data series and determine whether conditions are stable or changing," says Vandrup Martens.

Instrumentation

• Data logger CL2 (collects and transmits data)
• 3 sensors measure pH
• 1 sensor measures oxygen
• 4 redox sensors
• 5 temperature sensors
• Cautus Web - receives, analyses and converts data into information that can be read continuously