Egyptian archaeologists showed off white pumice Monday that they theorize was swept onto the northern Sinai desert by a tsunami triggered by the ancient volcanic eruption on Santorini island 530 miles (850 kilometers) away.
Traces of the solidified lava foam from the eruption have been found on the island of Crete and in southwestern Turkey, but the archaeological team now believes it also reached the Sinai site where they were digging at an ancient fort 4 miles (6.4 kilometers) from the Mediterranean coast.
The Santorini explosion in the 17th century B.C. was devastating. It sank most of the now-Greek island and killed more than 35,000 people of a thriving Minoan community.
The head of Egypt's Supreme Council of Antiquities, Zahi Hawass, said the discovery of the pumice would open a new field of study in Egyptology.
"Geologists will help us study how ... natural disasters, such as the Santorini tsunami, affected the Pharaonic period," he said.
A volcanologist at Greece's Institute of Geology and Mineral Exploration, Georges Vougioukalakis, was skeptical that the pumice could have traveled so far with a tsunami.
While noting that layers of ash from Santorini have been found in Egypt's Nile Delta, he told The Associated Press that he thought it more likely the floating pumice was carried to the Sinai by regular ocean currents.
The archaeological team found the pumice while excavating at Tel Habuwa in the desert northeast of Qantara, a town on the Suez Canal nearly 95 miles (150 kilometers) northeast of Cairo.
They were searching for Pharaonic forts that helped protect the Nile Delta from foreign invasion, and last month they uncovered remains here of an 18th Dynasty fort with four rectangular towers built of mud bricks.
"The pieces of lava stone were a surprise, but they were only part of the story," said team leader Mohamed Abdel Maqsud.
For the archaeologists, more significant was finding a fortress used by ancient Egyptians to expel the Hyksos enemy during the New Kingdom, a Pharaonic empire that lasted from about 1500 B.C. to about 1000 B.C.
The easternmost forts were so important that they were depicted in the reliefs on the walls of Karnak Temple in the ancient capital of Thebes — the present day city of Luxor, 300 miles (480 kilometers) south of Cairo.
Hawass did not elaborate on the geological tests that linked the Sinai pumice to Santorini, but said he was convinced more such lava would be found. "This is only the beginning," he said.
Associated Press writer Nicholas Paphits in Athens, Greece, contributed to this report.