Patent ID: 8753867

Claim:
A computer-implemented method of evaluating the amount of biodegradation, through the action of bacteria, of hydrocarbons trapped in a basin discretized into a set of cells, comprising: estimating a mean hydrocarbon saturation of the basin (S m ), a mean porosity of the basin (Φ m ), and a hydrocarbon density (ρ h ); calculating, in a computer processor, a mass M hp of hydrocarbons present in the basin, without taking account of the biodegradation, as a product comprising the mean hydrocarbon saturation of the basin (S m ), the mean porosity of the basin (Φ m ), the hydrocarbon density (ρ h ), and a volume (V p ) wherein hydrocarbons are trapped; executing, in the computer processor, a computer-implemented basin simulation, in order to determine physical and geometrical characteristics of the basin, the physical and geometrical characteristics comprising at least a hydrocarbon filling time (T r ) for the basin, and a mean depth (Z m ) of a given cell in the basin during the filling time; estimating the number of bacteria (N bact ) present in the basin and taking part in the biodegradation, including executing, in the computer processor, the formula N bact =10 (7.95−(0.64*log(Zm))) ; estimating a hydrocarbon consumption of the bacteria, from a ratio of an estimation of a mean carbon consumption of a bacterium (C bact ) and a ratio (R ch ) of a mass of carbon consumed to a mass of hydrocarbons consumed, wherein C bact ranges between 10 −11 and 10 −14 μg C per second, and R ch is in the order of 0.8 gC/gHC; calculating, in the computer processor, a mass M hb of hydrocarbons consumed by biodegradation, as a product comprising the number of bacteria (N bact ), the hydrocarbon consumption of a bacterium (C bact ), the hydrocarbon filling time for the basin (T r ), the volume (V p ) wherein hydrocarbons are trapped, and the inverse of the ratio of the mass of carbon consumed to the mass of hydrocarbon consumed (R ch ); evaluating and outputting the amount of biodegradation by calculating a mass ratio (R) of the mass of consumed hydrocarbons (M hb ) to the mass of hydrocarbons (M hp ).