Coal petrographic techniques have been used to trace the origin of coal used to produce artifacts by the Thule people in north-eastern Greenland. The coal artifacts were collected from the north-east coast settlements between 76°55'-80°18'N and date back to the 15th century A.D. The petrographic data suggest that they have a common source, the Middle Jurassic coals outcropping south of 75°15' in north-eastern Greenland. It is thus evident that the Thule people used local material rather than bringing the coal from the known "mines" in Arctic Canada. It also implies that contemporaneous Thule people groups along the east coast of Greenland were in contact and traded.
- Programområde 5: Natur og klima