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The goal of the present work is to simulate the effects of perforation misalignment on fracture initiation pressure (FIP). A 3D numerical model of the fracture initiation from a perforated wellbore in linear elastic rock is used to model FIP. This model is based on the boundary element method (BEM) and maximum tensile stress (MTS) criterion. Simulations enable studying FIP sensitivity to perforation orientation and finding the orientation that corresponds to the lowest FIP as well as the FIP change along the length and the circumference of the perforation tunnel. The data used were from different zones and blocks of a tight gas-bearing sandstone field in the Sultanate of Oman. Some practical applications of the study include the decisions on the type of perforation technique (i.e. abrasive jetting or explosive perforations), which greatly impact the economics of the fracturing treatments.

The goal of the present work is to numerically simulate the effects of wellbore orientation on fracture initiation pressure (FIP). These simulations support the study of FIP sensitivity to arbitrary wellbore position and finding the orientations that correspond to the lowest FIP. A 3D numerical model of the fracture initiation from a perforated wellbore in linear elastic rock is used to model FIP. This model is based on the boundary element method (BEM) and maximum tensile stress (MTS) criterion. The data used were from different zones and blocks of a tight gas-bearing sandstone field in the Sultanate of Oman. The amount and quality of available data allowed comprehensive model development. The model is built for the four blocks of the main field, but can be applied to the other blocks and fields. Since the equations and correlations are not empirical and not field-specific, the model is applicable to a wide range of conditions. Some practical applications of the study include selection of the optimum perforated intervals intended for fracturing stimulation in deviated or almost horizontal wellbores where different parts of lateral sections are not exactly aligned with principal stresses. Drilling wells in a particular direction to the principal stresses for the specific reason to reduce the FIP has not been tested to date and is a subject to further discussion.• Stronger completions • Revised (reduced) safety margins for the pressure during fracturing • Use of heavy brine for formation breakdown • Different (so called hybrid) fracturing schedules

In today's job market it is becoming increasingly important to demonstrate one's critical thinking and creative problem solving skills in addition to the traditional engineering knowledge. One effective method for improving these skills involves the use of interactive computer modules. Particularly, the simulation of faulty operation has also the advantage of adding uncertainty of industrial settings.This work will demonstrate one of the interactive computer modules developed at University of Michigan for troubleshooting, MicroPlant. This interactive computer program simulates the faulty operation of a micro-plant in which ethyl benzene is converted to styrene. It contains over forty possible faults, two of which are assigned randomly when the student signs on to the program. The program is designed to encourage the student to troubleshoot the plant with critical thinking skills in situation and decision analysis.

A recent series of tight gas discoveries in the Amin formation of the greater Fahud area represents some of the most exciting exploration success of this decade in the Sultanate of Oman. The structures have been evaluated as containing very significant amounts of gas locked in a challenging deep and hot environment requiring hydraulic fracture stimulation. Since their discoveries, the two primary challenges have been difficult breakdown of the formation and limited proppant placement during stimulation attempts. The early experience in the exploration and appraisal campaigns from 2009 to 2014 has led to fracture designs with conservative proppant amounts that could limit the full potential of the field. Several geomechanical studies have been commissioned in the past to guide completion strategies in well placement, perforation, and fracture stimulation design. The objectives of this study were to model hydraulic fracture initiation and breakdown in the three Amin zones (upper, middle, and lower) to provide some theoretical understanding of the impact of the different parameters on the observed field breakdown pressures. In agreement with field observations, the model showed that lowering the viscosity of the pad has a major impact in lowering the breakdown pressures. Consequently, current best practices include formation breakdown and hydraulic fracture propagation with low-viscosity fluids followed by proppant placement with high-viscosity fluids. When applied to tight gas formations in the Sultanate of Oman, the hybrid fracturing evolves from conventional designs for the purpose of successful fracture initiation, while still placing a successful job.