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The current study presents elastic properties model for Fulla Oilfield in northeast of Block 6 in south of Sudan. Due to the poor formation consolidation and relatively viscose fluid, reservoirs may predictably produce massive amounts of sand and numerous troubles were found in the field as a result of sanding. No documented researches were found to introduce good parameters for rock strength and rock failure conditions through the field. Therefore, an accurate technique for predicting rock failure conditions may yield good profits and improve the economic returns through preventing sand production from the formations. General correlations were presented to accurately describe rock strength parameters for the field; the work utilizes the application of the wireline porosities to be used as a strength indicator through the combination of rock mechanical theories with the characterization of Fulla oilfield. Log porosities (density, sonic and neutron) were calibrated with the core measured porosity, and the best matching porosity were correlated with the dynamic calibrated strength parameters by different correlations. The results support the evidence of the use of porosity as an index for mechanical properties; power functions were found more reliable than the exponential functions, and can be used with a high degree of confidence; also it is more accurate than the Shale Index model presented in pre-vious work for same field; however, the result does not support the direct linear expression pre-sented in the literature for other field due to the variations in the field conditions.

Recently, Frac packing was investigated to improve the economic returns of the reservoirs through the reduction of formation damage and controlling sanding from unconsolidated formation. The technique is applied for high permeability formations, in which the well production rate is affect by fracture conductivity rather than fracture length; therefore, short fat fracture with a good slurry concentration is required. The optimization of these parameters is the major factor for successful job; the optimization can be achieved through the combination of reservoir model with fracture model and tip screen-out (TSO) concept. On the basis of the formation characteristics, fracture length and conductivity with in-situ stress the effect of pump schedule was addressed for Tip Screen Out fracture through a well in Fula oilfield in Sudan. 3D fracture simulation software (FRACPRO PT) was used with TSO concept to address the effect of pump rate and proppant concentration on the obtained fracture. The study presented the proppant distribution is highly affected by the injection rate, and an injection rate of 3.5 was selected to avoid sanding as a result of bad proppant distribution. Also, it was observed that the fracture geometry is affected by pump rate and proppant concentration.

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This paper presents a geo-mechanical model for Fula oil field formation in Muglad basin in Sudan. The static mechanical rock properties measured on rock samples were calibrated with the dynamic wire line data run in the cored wells; empirical core-log relationships were developed to determine the formation mechanical properties and to estimate the critical formation drawdown pressures. The paper also looks at the stresses and loads induced near the wellbore. The calibrated log properties were used with some correlations to estimate formation strength and failure conditions to get reasonable results for the formations under study. Initial analysis indicates that a small amount of sand will be produced under any conditions; generally sand will be increased if the flow rate reaches a critical value