Zion Oil and Gas Inc. (NASDAQ: ZN) said it encountered free-flowing hydrocarbons while circulating drilling mud during open hole wireline logging and reaming at its Megiddo-Jezreel #1 well in Israel.

“We were cautiously optimistic given the amount of gas that accumulated in the well after returning from Shabbat after calling total depth at 5,026 meters [about 16,500 ft]. After making our first of three openhole logging runs, we decided to ream to bottom to clean the hole out in anticipation of our second logging run,” Dustin Guinn, president and COO of Zion, said in a news release. “After circulating the well, we experienced a continued and significant increase in gas followed by clear evidence of oil in our circulated mud from the bottom of the well.”

The company plans to drill up to another 70 m (230 ft) followed by openhole log work.

Oil and gas were encountered in the deeper part of the well, Zion CEO Victor G. Carrillo said. He added that the company could not comment on the commerciality of the discovery or its ability to successfully produce hydrocarbons from the well.

“We will provide further updates after we have adequate time to properly evaluate the logs and finalize our well testing program following the recent events,” Carrillo said.