*4.2.1 Effect of reservoir management on oil rate and basic sediment and water (BSW)*

Production parameters considered include; Flowing Tubing Head Pressure (FTHP), Gas-Oil-Ratio (GOR), basic sediment and water (BSW) and choke size. The management of the choke has relative impact on oil rate and basic sediments and water (BSW). Practically, water production within the first 2 years of production was zero and peak production (over 4750 BOPD) was observed between the first 2 years (**Figures 15**–**17**).

**Figure 15.**

*The effect of choke management on oil rate and basic sediment and water for well A4.*

**23**

**Figure 18.**

*Production history profile for well A2.*

**Figure 17.**

*Geologic Characteristics and Production Response of the N5.2 Reservoir, Shallow Offshore Niger…*

There was high FTHP corresponding to periods of high oil rate (**Figures 15** and **18**) and choke size not exceeding 30 inches. Between September 2001 and March 2004, there was steady increase in choke from 33 to 60 (see **Figure 17**), with similar trend in the BSW. It is evident that the management of the reservoir also

played a significant role on rapid fluid flow especially water.

*The effect of choke management on oil rate and basic sediment and water for well A8.*

*DOI: http://dx.doi.org/10.5772/intechopen.85517*

**Figure 16.** *The effect of choke management on oil rate and basic sediment and water for well A7.*

*Geologic Characteristics and Production Response of the N5.2 Reservoir, Shallow Offshore Niger… DOI: http://dx.doi.org/10.5772/intechopen.85517*

There was high FTHP corresponding to periods of high oil rate (**Figures 15** and **18**) and choke size not exceeding 30 inches. Between September 2001 and March 2004, there was steady increase in choke from 33 to 60 (see **Figure 17**), with similar trend in the BSW. It is evident that the management of the reservoir also played a significant role on rapid fluid flow especially water.

**Figure 18.** *Production history profile for well A2.*

*Sedimentary Processes - Examples from Asia, Turkey and Nigeria*

*4.2.1 Effect of reservoir management on oil rate and basic sediment and water (BSW)*

*The effect of choke management on oil rate and basic sediment and water for well A4.*

*The effect of choke management on oil rate and basic sediment and water for well A7.*

Production parameters considered include; Flowing Tubing Head Pressure (FTHP), Gas-Oil-Ratio (GOR), basic sediment and water (BSW) and choke size. The management of the choke has relative impact on oil rate and basic sediments and water (BSW). Practically, water production within the first 2 years of production was zero and peak production (over 4750 BOPD) was observed between the

**4.2 Production response**

first 2 years (**Figures 15**–**17**).

**22**

**Figure 16.**

**Figure 15.**

The continued water injection through the injector wells in the field could be another source of water production which has adverse effect on oil recovery especially for production wells proximal to the injectors.

The oil rate, Qo, as well as the liquid rate declined at the onset of water production in 2001 and afterwards liquid rate had remained constant at different choke sizes. The oil rate declined further as water cut increased (**Figures 15**–**18**). The total cumulative oil production as at January 2011 is about 67.18 MMSTB; this represents 43.91% recovery factor. However, there is still recoverable oil remaining in the reservoir, which can only be recovered if certain field operational conditions are considered.
