EIN GEDI, Israel — Five miles out, nearly to the center of the Dead Sea, an international team of scientists has been drilling beneath the seabed to extract a record of climate change and earthquake history stretching back half a million years.

The preliminary evidence and clues found halfway through the 40-day project are more than the team could have hoped for. The scientists did not expect to pull up a wood fragment that was roughly 400,000 years old. Nor did they expect to come across a layer of gravel from a mere 50,000 to 100,000 years ago. That finding would seem to indicate that what is now the middle of the Dead Sea — which is really a big salt lake — was once a shore, and that the water level had managed to recover naturally.

“We knew the lake went through high levels and lower levels,” said Prof. Zvi Ben-Avraham, a leading Dead Sea expert and the driving force behind the project, “but we did not know it got so low.” Professor Ben-Avraham, a member of the Israel Academy of Sciences and Humanities and chief of the Minerva Dead Sea Research Center at Tel Aviv University, had been pushing for such a drilling operation for 10 years.

The idea was to bore under the sea and extract a continuous geological core that, once analyzed, could supply information of global importance on natural processes and environmental changes.