IVZ media thread, page-3071

Meteoric water enters the formations in the hills, leading to the introduction of organisms in the subsurface that may biodegrade the hydrocarbons

I can buy the aquifer, connected to the surface. In the good case this can be a good pressure support for the oil production. In the bad case it flooded the reservoir.

But I do not buy the biodegradation. Biodegradation at surface or close to surface yes but not in the deeper parts of the reservoirs. Bugs can live everywhere, but above a certain temeperature (about 60, 70°C) you find less bacteria surviving this temperature. Start with 20°C and add 3°C every 100 m vertical depth for calculating the temperature for the 200, the 250 target etc. Moreover bacteria like the longer molecule chains of oil more than methan. There are bacteria that eat CH4 as well but there are more oil eating bacteria.Therefore I see much less bacteria risks when the targets have got gas. Moreover the oil sample descriptions from the old Mobil reports do not sound like biodegraded oil - at least for me and of course oil at the surface, the outcropp that has contact to oxygen is degraded. But there is no O2 in deeper reservoirs. I appreciate the short videos, produced by Trove but here I challenge the biodegradation and I would say this biodegradation is just a small , neglectable risk.