The reliefs at Gobekli Tepe were carved more than 11,000 years ago on giant limestone blocks. Professor Tristan Carter is seen here beside an image of a creature, possibly a reptile.
Gobekli Tepe is located in southern Turkey near the modern-day city of Urfa. It contains at least 20 stone rings (circles within a circle) that date back more than 11,000 years. T-shaped limestone blocks line the circles and reliefs are carved on them. Long ago, people would fill in the outer circle with debris before building a new circle within. In this photo Professor Tristan Carter is shown alongside one of the rings.
Obsidian artifacts from Gobekli Tepe are analyzed using Proton Induced X-Ray Emission Spectroscopy (PIXE) at the Louvre museum in Paris. The test helps match up the chemical composition of obsidian with the volcano from which it came.
The stone-circle structures and pillars are shown here at Göbekli Tepe, in southern Turkey.
Volcanoes near Lake Van, in eastern Turkey, were identified as a source for some of the Gobekli Tepe obsidian in the new study. It is located about 150 miles (250 km) away.
Cappadocia, in central Turkey, was identified as a source for some of the obsidian found at Gobekli Tepe. It is located about 300 miles (500 km) away from Gobekli Tepe, about the distance between New York City and Buffalo.