Opportunities in the Eastern Mediterranean

Neil Hodgson - VP geoscience - Searcher Seismic

Gareth Freeston Smith - Head Sub-surface for Israel - Energean Oil and Gas

Owen Sutcliffe - Manager, Exploration Insights - Landmark Exploration Insights

Outside of the well-established play fairways of the Nile Delta, the offshore Eastern Mediterranean is without question a high-profile emerging frontier for exploration. Two significant plays in this frontier are now documented with the challenge being to map likely play extent. These plays comprise the predominantly Early Miocene turbidites of the Tamar sandstones of the Levant Basin and, more recently, Cretaceous to Miocene carbonate buildups typified by the Zohr discovery. In both cases, the dominant phase of hydrocarbon appears to be dry biogenic gas. This presentation introduces the necessary elements to evaluate these incipient fairways and develop new play concepts, particularly in underexplored areas.

Five primary geological research themes are relevant for reducing exploration risks in this region. They are evaluated using regional geological concepts to aid the delivery of models for exploration success. Each of them is discussed and a framework for their evaluation is provided.

The first theme investigates the provenance of the quartz-prone reservoirs in Early Miocene turbidites of the Levant Basin. These sandstones are extensive, amalgamated into sheet-like bodies, deposited during multiple sequences of sea level fall and, with the exception of the Nile Delta, are flanked to the east by slopes that are essentially out-of-grade. A Paleo-Nile provenance is likely, with regional tectonic episodes on this delta limiting the delivery of sands to the Levant Basin to the Early Miocene. In the Middle Miocene, these clastics could have been diverted into the underexplored Herodotus Basin.

The second theme shows the scale and extent of offshore carbonate play fairways and the ability to predict or identify the occurrence of such carbonate buildups that are comparable with Zohr. Their growth is enhanced where clastic poisoning is limited; in the Miocene (at least), this can be modeled by mapping the basinward diminution of clastics around paleo-highs from seismic sections. Platform carbonates probably developed along the Cretaceous passive margin onto outboard highs that formed during Triassic and Jurassic rifting, so prospective targets are expected to be located along these early Mesozoic structural trends. At Zohr, reservoir quality could have been enhanced by periods of subaerial exposure and subsequent karstification, so larger scale buildups situated on the longest-lived structures that remained elevated near sea level could have better reservoir potential.

The third theme shows the nature and timing of charge, its relationship to trap formation, and the potential for non-dry gas and liquid phases in the resource portfolio. Regional variations in heat flow are poorly identified and are also likely to be influenced by the occurrence of thick Messinian salts. Therefore, the creation of reasoned, regional conditions and multi-scenario burial models is the only way to best evaluate the range of opportunity in these domains.

The fourth and fifth themes are similar and reflect stratigraphic uncertainty around the stratigraphic composition of sub-Miocene plays in the Levant Basin and the stratigraphy of the Herodotus Basin, respectively. These uncertainties are best evaluated through the adoption of a holistic appreciation for regional geological development and a robust model for the broad-scale structural organization.

The future exploration potential of the Eastern Mediterranean is considered significant and insights into exploration are best identified using an integrated regional evaluation of its geology that is delivered by integrating sequence stratigraphic and geodynamic models.







Landmark Exploration Insights
Landmark Exploration Insights (formerly Neftex), is a product family within Landmark, a business line of Halliburton. We specialise in the collation, integrations and interpretation of large geoscience dataset and the delivery of these as subsurface models. We are recognised as industry leaders in the provision of web-based sequence stratigraphic products and their global application. Our integrated global geological database - the Neftex Earth Model delivers data, knowledge and insight to help our clients better understand geological risk in their exploration and investment activities.

Felicia Winter - Interpretation Geophysicist/Potential Field Analyst - TGS

Matthew Pyett - Project Geoscientist, New Ventures - Africa, Mediterranean & Middle East - PGS

Karyna Rodriguez - - Searcher Seismic