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Petroleum play in North Pakistan comprises of naturally fractured reservoirs (NFR) both in clastics and carbonates. These fractures play key role in the determination of reservoir quality and production behavior of the formations and is a subject of interest for E & P companies particularly working in Kohat Plateau.In TAL Block, naturally fractured Lockhart formation has very low matrix porosity and fractures provide the main source for storage and fluid flow in it. It has also been observed that all the fracture sets in carbonate reservoirs do not contribute to flow. Flow variations have been observed with different fracture trends identified from open-hole logs based on their connectivity, fracture apertures and secondary porosity. This leads to the development of an integrated approach using existing information from open hole logs, image logs, formation tester and production logs to optimize the reservoir modeling, history matching and selection of future perforation intervals.In this paper, data from six wells located in different structures in TAL Block has been utilized to study the behavior of naturally fractured carbonate reservoir. During the study, it was observed that in some wells, the top part of Lockhart formation was contributing more to production while in others, the bottom part was more productive. These flow variations could be associated with different fracture trends, their connectivity, fracture apertures and secondary porosity. This problem was addressed by sub-dividing Lockhart in to different layers/facies based on fracture evaluation (types, density, secondary porosity, nodularity and rock texture), open hole logs, formation tester results and production logs interpretation.

In one of Operator; they want that Asset teams must work closely and collaboratively to achieve results in Petrophysics projects. A project data management (PDM) effort established a system that enables collaboration for petrophysical teams and that makes quality-controlled data available for each project. A separate of objective in the effort was the documentation of business rules for the petrophysical asset team. Centralization of PDM is the key to enabling collaboration and the provision of quality-controlled data. Therefore, one focus of the project was centralization. While implementing the technology, the project team also prepared the "agreed" business rules document (BRD). This BRD will guide the petrophysical teams to properly maintain their project data. The BRD lays down standards and supports common understanding. Additional steps before the implementation of technology were performing QC and cleaning the existing data. Centralization of the PDM enabled some key workflows, which cannot be achieved in standalone projects. Specific achievements of this project included enabling collaboration, retaining knowledge, setting up business rules, and performing quality control. Enabling collaboration was the key objective of the project. After the implementation, it was noted that using the system, team members can work on the same "physical" project without disturbing each other's work. Any updates in the project are communicated to the entire team. The updates are accompanied by user notes to enhance team understanding. Collaboration enables teamwork during the project timeline. However, for the E&P companies, it is also very important to keep the "knowledge alive" for later work on the same project by other teams. Long-term knowledge retention has been enabled by the ability to maintain captions, notes, and quality parameters. These "pieces of knowledge" will help future teams understand the thought process behind the results. Setting up the BRD enabled alignment of the end users, IT teams, and data management teams. The one-time quality assurance of the existing project data and raw data has aided the operator in implementing the centralized PDM and workflows.

Hydraulic fracturing is one of the most effective methods of improving the deliverability of low permeability wells. Hydraulic fracturing in a rich gas condensate field has earned cost benefits by reducing number of infill wells, producing condensate drop out from reservoirs and increasing overall productivity of oil and gas. The target development well was drilled and completed in September 2013 and post completion testing rates as well as pressure build up analysis indicated severe formation damage issues and requirement for hydraulic fracturing. In the same field hydraulic fracturing was carried out earlier in other wells but yielded mixed results. In some of the wells 2-3 times increase in productivity was observed while in some wells, the results were below expectations, despite placing ~100,000 lbs of proppant. In one of the well, formation break down did not occur. Utilizing prior frac experience it was decided to optimize the upcoming frac job but at the same time not to compromise on the frac quality. Extensive pre-job evaluation and planning which included review of available logs and previous frac data, development of 1D Mechanical Earth Model (MEM), frac modeling, implementation of Channel fracturing technique, optimization of fracturing chemical and proppant volumes was done to get maximum benefit of this major well stimulation job. As a result of these efforts frac jobs of the target sandstone reservoirs was completed successfully and the well was put on production in minimum clean-up and post frac testing time. As a result of above effort in planning and optimization of frac job at the target well, significant increase in production was observed which exceeded the operator expectations and raised the confidence level in 1D MEM application for hydraulic frac design (i.e. geomechanics) and the new frac technique by the service company. Based on post frac results, these techniques are being utilized in the upcoming wells in the target field.