RE: Methane concentrations23 Feb 2024 23:30
Leviathan
"if the gas is thermogenic, then the chance of deeper thermogenic oil potential could be reduced or even excluded, while biogenic gas would leave an opportunity open for deeper thermogenic systems which could include oil. Publicly available knowledge is developing quickly and it is now accepted that the gas that has been discovered so far in fields such as Tamar and Leviathan is of biogenic origin. As a result, exploration for deeper thermogenic systems is now under way."
The Messinian Salinity Crisis resulted in:
1. Pressure drop at surface, propagated deep into the subsurface
2. Temperature increase at surface, propagated into the subsurface (attenuation with depth)
3. Rapid salt deposition
Likely impact on the petroleum systems:
1.Shallow biogenic system (first 1000m)
2. more fluids in reduced pore space
3. Fracturing and gas leakage
4. Deeper biogenic system conserved (Tamar, Leviathan, Aphrodite)
5. Speculative deep petroleum systems are more likely to be preserved
Source: Assessment of Controlling Factors in Mixed Biogenic and Thermogenic Petroleum Systems – A Case Study from the Levantine Basin. Bjorn Wygrala et al