The Death and Rebirth of the Tamar/Leviathan Play Concept, Offshore Israel

James M. Peck

Noble Energy (then Samedan) and partners drilled in 1999 the Mary B-1 well that discovered approximately 1 TCF of gas in an exceptional Post-Messinian Salt Pliocene reservoir. As a reaction to that success, British Gas and Israeli partners committed significantly to the trend by acquiring Permits offshore Israel that essentially surrounded the Yam Tethys Project.

BG failed to identify additional Mary B or Gaza Marine analogues. However, BG identified on 2D seismic grid two very large sub-Salt four-way dip-close structures, the Tamar and Dalit Prospects, in the distal portion of the Eastern Mediterranean Basin. Both structures exhibited amplitude anomalies.

Elements of the BG internal regional evaluation included the following;

1. A seismic interpretation of an extensional tectonic regime with a thick Tertiary-dominated distal stratigraphic section and a very thin and deeply buried Mesozoic section.

2. BG burial histories invoked a Petroleum System anchored on a shallow pre-Salt Tertiary biogenic (methane gas) source rock in the distal Basin.

3. Only pre-Salt Tertiary reservoirs would be available at drillable depths BG began to search for partners in 2004. Approximately 120 companies including Noble (Samedan) were approached. All companies declined the BG farmout. BG dropped all licenses in 2005 and exited Israel. From 2003 to 2005, the author, as a consultant entered into collaboration with TGS-Nopec to interpret their regional 2D seismic data offshore Lebanon, Israel and Egypt.

Elements of the resulting interpretation of the TGS-Nopec regional 2D seismic, over the distal portion of the Basin included the following:

1. A “bottom-up” seismic interpretation framed by the Basin’s tectonic history understood to include a Late Triassic to Early Jurassic Rift Phase, a Middle Jurassic-Early Cretaceous Passive Margin (Sag) Phase, a Late Cretaceous- Eocene Alpine inversion Phase, a Latest Paleogene-to-Miocene Internal Plate Adjustment Phase and a Pliocene Flooding & Reactivation Phase.

2. The primary conclusion of the “bottom-up” methodology was that the Mesozoic system was at depths that resulting burial histories postulated that traditional Early Cretaceous and Middle Jurassic source rocks could be the anchor for a thermogenic Petroleum System.

3. A secondary conclusion of the “bottom-up” seismic interpretation methodology was both Tertiary & Mesozoic turbidite fans available as reservoirs in the distal portion of the Basin.

After the exit of British Gas, the remaining Israeli companies in the Projects hired the author to assist them in attempting to farmout the Tamar/Dalit Projects to a qualified deep-water operator based on the elements of the ”Bottom-up” methodology.

Subsequently, Noble Energy farmed into the Tamar/Dalit Projects.

Noble Energy and partners drilled the Tamar-1 discovery in 2009 that contained approximately 240 billion mm³ of gas (mainly methane) reserves in Early Miocene/Oligocene reservoirs.

Noble energy and partners subsequently farmed into the Leviathan Project to the west of The Tamar discovery and drilled the Leviathan-1 discovery in 2010 (approximately 450 mm³ gas (mainly methane) reserves in Early Miocene/Oligocene reservoirs). The partnership subsequently drilled deepened the well to targets below the initial Early Miocene/Oligocene reservoirs. At last report, gas and condensate reported to have been found in Cretaceous reservoirs in the deepened well vindicate the postulation of a thermogenic Petroleum System based on the “bottomup” interpretation methodology has been vindicated.

Elements and conclusions of the “bottom-up” methodology should be applied to other parts of the distal Eastern Mediterranean Basin to assist in the delineation and promotion of pre-Messinian Salt play concepts.

AAPG Search and Discovery Article #90161©2013 AAPG European Regional Conference, Barcelona, Spain, 8-10 April 2013