

Fig. 2 Saudi Arabia and Ghawar production from a presentation given by Frederik Robelius (pdf here). Click To Enlarge.

Hubbert Linearization Applied on Ghawar Only



Fig. 3 Left or top Chart: Hubbert Linearization of Ghawar with the 95% confidence interval (red dashed lines). Only blue points are used in the fit.

Right or bottom chart: resulting logistic curve with the 95% confidence interval (red dashed lines). The green lines are Euan Mearns's base and high forecast for Ghawar (details here). The red circle indicates the year 2003.

URR Q(2003) K (%) t half 100.59 ± 8.59 Gb 61.49 Gb 7.41 ± 3.65 1997.00 ± 3.25 Table I. Logistic curve parameters for Ghawar.

What About the Rest of Saudi Arabia Oilfields?



Fig. 4 Left or top Chart: Hubbert Linearization of Saudi Arabia crude oil + condensate (EIA) minus Ghawar production with the 95% confidence interval (red dashed lines). Only blue points are used in the fit. Right or bottom chart: resulting logistic curve with the 95% confidence interval (red dashed lines). The red circle indicates the year 2003.

URR Q(2003) K (%) t half 60.13 ± 12.78 Gb 39.99 Gb 7.79 ± 3.7 1994.25 ± 9.25 Table II. Logistic curve parameters for the Other Fields.

Hubbert Linearization on Saudi Arabia



Fig. 5 Left or top Chart: Hubbert Linearization of Saudi Arabia crude oil + condensate (EIA) with the 95% confidence interval (red dashed lines). Only blue points are used in the fit. Right or bottom chart: resulting logistic curve with the 95% confidence interval (red dashed lines). In green, the domestic consumption (all liquids). The red circle indicates the year 2007 .

URR Q(2007) K (%) t half 200.21 ± 24.12 Gb 114.78 Gb 6.06 ± 2.90 2002.25 ± 4.9 Table III. Logistic curve parameters for Saudi Arabia.

Summary

URR (Gb) Produced (Gb) Reserves (Gb) Stuart Staniford (2007) 90-102 42-62 28-60 Euan Mearns (2007) 96.8 - 115 69.8-79.2 27.0-35.5 Logistic

100.6 ± 8.6 61.5* 39 ± 9 Table IV. URR estimates for Ghawar. *2003.



Fig. 6 The red circle indicates 2007 estimate. Click To Enlarge.

2003 2007 2008 2010 2012 Ghawar Only 5.17 4.46 [3.64 - 5.34]

4.34 [3.51 - 5.18] 4.08 [3.26 - 4.92] 3.80 [3.01 - 4.63] Other Fields 3.61 2.53 [1.20 - 3.97]

2.44 [1.06 - 3.89] 2.25 [0.95 - 3.68] 2.06 [0.84 - 3.45] Total (Gh+OF) 8.78 7.99 [4.84 - 9.31]

6.78 [4.57 - 9.07] 6.33 [4.21 - 8.66] 5.86 [3.85 - 8.08] HL on Saudi Arabia (HL-SA) 8.78

8.63 8.06 [6.40 - 9.70] 7.87 [6.15 - 9.61] 7.63 [5.87 - 9.44] Table V. Production forecasts in mbpd. Bracketed values in italic are 95% confidence intervals Total is the sum of Ghawar and the Other Fields.

URR Gb Remaining Gb Recovery %2 Notes Parabolic Fractal Law 1 200 85 29 C+C only Ace 175 63 25 C+C only Pre-nationalisation 211 91 30 minimum Mearns 240 120 34 minimum, C+NGL Mearns 200 86 29 minimum, C+C Logistic 200 ± 24 85 ± 24 25-32 C+C only Ghawar+Other Fields 161 ± 21 46 ± 21 20-26 C+C only Campbell 275 155 39 C+C only Saudi official 384 264 55 BP+produced Table VI. Summary of available URR estimates for Saudi Arabia. 1assuming a total of 400 fields discovered. 2Note from Euan: The recovery factors are based on an ussumed 700 Gbs of original oil in place. This is the figure reported by Baqi and Saleri and by Colin Campbell.

Maintaining production flat at the 2004 level and compensating for Ghawar decline will require a new supply growth of 2-3 % per year. Maintaining exports flat at the 2004 level and compensating for Ghawar decline will require a new supply growth of 4-5 % per year.





Fig. 7 The red circle indicates 2007 estimate. Click To Enlarge.



is the honeymoon over?

The Hubbert Linearization technique is applied on the curve profile above and we get the following result:Parameters of the logistic curve are given in Table I. We can see that the resulting URR as well as the future decline are close to Euan Mearns and Stuart Staniford estimates. Note also that the logistic growth rate (K) is relatively high suggesting that current yearly decline rate for Ghawar is 2.62 ± 1.30 %/year and could reach 3.65 ± 0.56% in 2010.Using EIA's numbers for Saudi Arabia (crude oil + condensate) minus the above logistic model for Ghawar we can estimate the oil production from other fields. The resulting production profile is much more tortuous with a big drop in production from 1982 to 1990. The resulting fit gives an URR around 60 Gb and has a wider confidence interval (almost 25 Gb). We can see a big rise in production in 2003 which probably has continued in 2004-2006Now, let's compare or previous two-stages result with the HL performed on the total C+C production.The URR resulting from the Hubbert Linearization applied on Ghawar is consistent with previous estimates.Different forecasts are summarized in Fig. 6 and Table V below. The two stages forecast is close to Ace forecast whereas the HL-SA forecast is closed to Euan Below is a brief summary of available URR estimates for Saudi Arabia initially compiled by Euan here Assuming that Ghawar will follow a terminal logistic decline as shown on Fig. 3, new supply growth from Yet-to-be-find or Yet-to-be-developed oilfields is unprecedented:

Further articles about Saudi Arabia:

by Stuart Staniford

by Euan Mearns

by Heading Out

by Ace