When doctors wish to gain a better understanding of what is going on inside a patient’s body, they will perform an X-ray to construct an “internal map” of the body and, using their years of experience, will analyze the representation it produces and recommend a best course of action based on what they see. In oil and gas basin modeling, the same concept applies.

Nutech offers an integrated set of technologies that together provide a comprehensive and evolving picture of a reservoir across the entire life cycle of an asset via five areas of expertise: petrophysical analysis, core analysis, completion engineering, reservoir mapping and modeling, and reservoir engineering. The company has named this collective approach “reservoir intelligence.”

Reservoir intelligence is the integration of a number of these five disciplines related to reservoir modeling with the aim of extracting as much information as possible from the available data. Similar to combining multiple technologies like MRI and CT scans, the purpose is to provide the best understanding of what exactly is going on under the surface. The enhancement of knowledge and understanding that this approach provides enables companies to add value with improved intelligence and the ability to make better business decisions.

Disciplines in reservoir intelligence
Reservoir intelligence is assimilated by experts in five in-house teams and gathered using innovative technology and processes. NULOOK, for example, is an enhanced petrophysical analysis that uses conventional openhole well logs and forms the basis of integrated reservoir characterization processes that are used across all disciplines in reservoir intelligence. In the realm of completion engineering, the NUSTIM completion process is an eight-step design procedure that links a normalized reservoir textural analysis to past well records and history obtained in a field. Once this linkage is established, the process is then used to predict well behavior prior to completion. By way of this process, the optimal completion strategy for a new well or recompletion opportunity for an older well can be achieved.

In the realm of static property modeling, the NUVIEW process takes advantage of the textural analysis and the key petrophysical outputs to build models that allow users to calculate original oil in place and devise infield development plans. In the realm of dynamic modeling and simulation, NUVISION connects the dynamic behavior of reservoir fluids pressure and well completion and production information to the equation of field and reservoir development optimization.

Knowledge is power
In today’s low-cost environment, knowledge is power. Increasingly, oil companies need to maximize the use of their own data and the public data available to them. Often companies invest significant capital in acquiring data and information, drilling and logging wells, and taking samples of rock out of the well location and having the cores analyzed. However, optimal use of the data is not always achieved, and wells are continually drilled with no data collected at all.

By making full use of all the available information and using a combination of approaches to fully understand the reservoir and develop reservoir intelligence, better decisions can be made that take into account all of the different property variations across the basin and ultimately improving economic return.

Leveraging external expertise
There are many small oil companies that do not have either the expertise or the in-house tools required to perform effective basin modeling. By incorporating the reservoir intelligence group as part of their asset team, companies like these can leverage advanced technology and resources to work alongside their team.

The process works as follows: A client drills a well and a model is built using well, seismic and other available data. That model is then used to deduce what would happen if another well was drilled in certain locations or if two or three wells were drilled. The data are processed to characterize the reservoir, and then a model is built. Scenarios are modeled before investment is committed to drilling and completions. This is performed via an ongoing process of simulation and choosing the best location for the next well, drilling that well and updating the model in a continuous process over the years.

Shale basins: viewing the old through new eyes
In each basin the company has about 17 different studies. These shale studies (or basin studies) are distributed through all the major shale plays in the U.S. and Canada, with some in Europe and globally (Figure 1).

The company specializes in building a better analytical model using vintage data. The decision was made to look at older wells that were originally drilled for conventional reservoirs, bypassing the shale in a time before shales were considered valuable. The log data from these wells is now, after a period of time, publically available.

A database of these wells was constructed and a logging analysis method was developed to determine the characteristic of the reservoir (Figure 2). The reservoir characterization from these older wells and well logs enabled the construction of basin models, which are large 3-D models of the entire basin using key outputs and the shale vision processing to distribute the shale properties across the entire basin. These 3-D models are converted into maps, and clients can then see where the optimal areas are located within a basin and focus their efforts accordingly.

A number of different shale properties are modeled: petrophysical properties like porosity and shale permeability, structure, net thickness, water saturation, oil or gas in place, and geochemical composition of the basin is analyzed. This all enables a calculation of the in-place hydrocarbon, extraction strategies or the value of the basin for targeting different acreage positions within the basin.

The basin studies are updated with additional wells as the information becomes public. Since there are increasing amounts of production data from the operators, the production or the well performance aspects are being incorporated alongside static reservoir properties to determine a better, more accurate representation of which properties impact well performance. With this information, the team can identify which property or which combination of properties predicts well performance and can forecast what a typical well would perform like in new locations within the basin.

A transparent conclusion
Being able to analyze large static property models across the basin allows the company to perform additional work with clients to optimize well completion, spacing and placement within the reservoir to extract as much hydrocarbon as efficiently and economically as possible. An area can be cut from the large model to build a higher resolution model of the selected area. Dynamic simulation work can then be performed on the smaller model.

Reservoir intelligence gathers all the data that illuminate the properties of a reservoir in an integrated fashion. The purpose of doing this is to improve overall knowledge about the reservoir. In turn, this knowledge fosters an improved degree of intelligence behind the decision-making processes in determining the most economical way of extracting hydrocarbons.

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