ERHC Energy Inc (ERHE)

[Curious62]

Biogenic gas (pure methane) is a by product of bacterial activity. Biogenic activity only occurs below a certain temperature (i.e. this activity occurs at relatively shallow depths). The bacteria feed on higher chain organic molecules, that from which oil originates in a thermogenic process. The process required for generating liquid hydrocarbons requires higher temperatures (which kill bacteria). Therefore, biogenic gas is generated in a different location than that which generates oil. The occurrence of biogenic gas does not preclude oil deeper or at other locations. But it does mean that thermogenic products have not migrated to this exact location. Dry gas has less caloric value and, therefore, less $$ value than wet gas (higher caloric value) and liquids.

Gas caps are, by definition, at the "cap" (top) of the structure within a given horizon. One almost always drills the top of a feature first. Its possible that gas and oil can be segregated by depth in the structure and by drilling deeper in the same location, heavier hydrocarbons (liquids) will be found. Hydrocarbons can also be (and usually are) segregated within the same reservoir by depth. This mean its possible to explore for oil in these same horizons as they extend off the flanks of the structures. In effect, the reservoirs look like upside-down "U-tubes", with the lightest gas trapped on top and increasingly heavier hydrocarbons down the "legs" of the reservoirs. Extensive geophysical work would be done to determine if the "edge" of the gas cap can be identified. Below that point, oil might be found.