The eastern Mediterranean, particularly offshore Israel, is proving to be a sort of natural gas behemoth.
For many years, Israel appeared to have been left on the short end of the stick, so to speak, when the massive hydrocarbon deposits common to this part of the world materialized.
A few small oil and gas deposits were discovered intermittently, but that was it.
But now there seems to be a new story emerging – a history-making exploration/development endeavor that doesn’t involve shale.
This story began when Noble Energy arrived on the scene in the late 1990s, when it was known as Samedan. The company ultimately tapped into enormous supplies of natural gas offshore Israel in the Levant Basin in the eastern Mediterranean Sea.
Its subsalt Tamar natural gas discovery, which was drilled in approximately 5,500 feet of water, was the largest conventional gas discovery in the world in 2009. The target Oligo-Miocene-age clastics at Tamar occur at depths of approximately 15,000 feet subsea.
Until the Tamar discovery, these reservoirs had never been tapped into by the drill bit.
Noble operates Tamar, where it has a 36 percent working interest. Other owners include Isramco Negev 2, Delek Drilling, Avner Oil Exploration and Dor Gas Exploration.
To date, Noble and partners have drilled six successful subsalt exploration wells in Oligo-Miocene reservoirs in the Levant Basin, discovering approximately 37 Tcf of natural gas.
Its Leviathan field to the west of Tamar is estimated to hold as much as 18 Tcf, with the most recent number for Tamar upped to 10 Tcf.
Noble’s other natural gas discoveries in this deepwater exploration play are Dalit, Dolphin, Tanin and Cyprus A.
Plenty to Go Around
Prior to its subsalt exploration here, Noble made some Plio-Pleistocene post-salt finds to the south of Tamar in shallow water.
The first of these was the Noa-1 in 1999. The 1 Tcf Mari-B field went on production in 2004, followed by Noa and the recent Pinnacles discovery, which both began producing in 2012 via the Mari-B platform.
These finds, while respectable, tend to be overshadowed by the results of drilling activity to the north.
“The main subsalt play area is over 10,000 square kilometers in water depths of approximately 1,300 to 1,700 meters,” said AAPG member Dan Needham, development geoscience manager of Noble’s Eastern Mediterranean Business Unit.
“The Oligo-Miocene reservoir section is comprised of thick deposits of alternating thin silts, mudstones and sandstones,” he said, “deposited by sandy turbidites in a deep water setting.
“At Tamar, there are over 250 meters gross thickness of high quality reservoir with greater than 20 percent porosity and more than 500 millidarcies permeability,” Needham noted.
“Leviathan is a faulted four-way closure, reaching as large as 300 square kilometers,” he said. “The gas is biogenic in origin and comprised of 99 percent methane, the same as Tamar.”
The Tamar field was put online March 31, with the gas flowing from the field to the Tamar platform and on to the Ashdod Onshore Terminal.
Israel reportedly has exports to the European markets in its crosshairs.
There’s considerable ongoing chatter about an Israel to Turkey pipeline, and judging from some of the print media reports, this appears to be a possibility. However, the ever-shifting geopolitics in this general part of the world dictates that uncertainty is the only certainty.
For now, the gas is being used to meet Israel’s domestic needs.
“We have up to 1 Bcf per day capacity from the facilities at Tamar, and we have the ability to expand to 1.5 Bcf in the future,” Needham said. “We’re looking to average 700 million a day this year.
“What’s unique about this marketplace is we sell gas directly to the user in Israel,” he noted. “There’s no midstream buffer, like the Henry Hub and such.
“We have peak capacity in excess of our daily average production because of production swings in a 24-hour day,” Needham said.
“They need more gas during the day than at night, and they need more in the summer than the winter, so we have to have this peak capacity that’s above what we’re averaging,” he explained. “Sometimes we hit peak capacity, but it’s more of an instantaneous occurrence.”
Revving the Ferrari
The huge Leviathan discovery is not yet producing, and a startup date hasn’t been announced. Among other obstacles, facilities are limited in places and there are commercial issues to be resolved, such as export approvals and more.
The reservoirs are capable of delivering high rates of production.
“Someone commented that it’s like having a Ferrari, but you have to drive it through a school zone,” Needham quipped.
Even before these enormous discoveries, the U.S. Geological Survey considered the hydrocarbon potential of the Levant Basin to be significant enough to undertake an assessment of undiscovered oil and gas resources.
The study, which was released in March 2010, estimated a mean 1.7 billion barrels of recoverable oil and a mean 122 Tcf of recoverable gas in the Levant Basin province.
Now that Noble has discovered over 37 Tcf, just in the Oligo-Miocene reservoirs in the basin, it’s time to ask what’s on tap for an encore.
“We’re drilling an exploration well in Israel called Karish,” Needham said. “After that, we plan to drill an appraisal well offshore in Cyprus.
“We’re also looking at a deeper oil play,” he said. “We hope to drill a well to test that concept probably late in 2013 or early 2014.”