Today’s operating companies are facing data and information overload.

Data overload comes from the exponential increase in the amount of data acquired by permanent sensors of all types. Data should be a blessing but they often turn out to be a curse, as one must pan for gold amongst the mountains of data stored in multiple historians. The consequence is that today’s engineers waste 50% of their time fighting with data, not using them, and the problem is growing.

To face dynamic data overload KAPPA developed Diamant Master. This clientserver solution dynamically gathers, smart filters and stores permanent sensor and production data and prepares it for analysis simply, quickly and largely automatically. Diamant Master is also a comprehensive surveillance tool that can create derived data, detect anomalous events and raise alarms.

Coupled with data overload there is information overload. Using conventional tools there is simply no time for engineers to perform analyses and make decisions on all candidate data. Although this is still an area of active research, KAPPA today’s answer is Ecrin.

Ecrin is an integrated engineering suite that aims to be the best collection of analysis and modeling tools for reservoir dynamic data. Ecrin modules include pressure transient analysis (Saphir NL), production analysis (Topaze NL), fullfield history matching (Rubis) and well performance analysis (Amethyste).

Diamant Master and Ecrin provide what our users asked for: ergonomic tools that integrate, navigate and communicate within a single environment, cutting waste, time and training overheads.

Whenever a fluid is produced or injected into the reservoir, the diffusion produces changes in pressure and temperature that may be recorded in various places. Combine this data with the production and / or injection rate history and we have what we call Dynamic Data.

Not so long ago, dynamic data came only from well tests. Analysis comprised specialized plots and dedicated analytical models. For KAPPA, this was the time of Saphir, our then ‘welltest analysis’ software.

Today the sources of dynamic data are multiple and apply at various scales in time and space. Analyses are also more complex. Different methodologies have to be applied, sometimes using the same data, sometimes not. However, all these techniques apply to the same reservoir and wells, and the truth is in the data. The name of the game today is to build a puzzle from little pieces coming from everywhere.

There is a long list. It starts with pressure transient analysis (PTA), the new name for welltest analysis, and production analysis (PA). On the scale and lifespan of the reservoir we can history match (HM) production, pressure and temperature data.

It is also possible to obtain a vertical profile of the field contribution with production logging (PL) and formation tests (FT). To bring all this to datum the output of a well performance analysis (WPA) tool is required.

For KAPPA this is the time of the integrated Ecrin suite. Ecrin is the software environment under which all KAPPA dynamic data analysis modules operate. By running under a single executable Ecrin provides complete interconnectivity between the modules and allows data sharing and technical objects by drag-and-drop, saving time, repetition and frustration.

Permanent downhole gauges (PDG) constantly monitor downhole pressures and are a data-rich witness of what is happening in the well and the reservoir. PDGs provide long-term data to run production analysis and short-term data, from incidental shut-ins, to perform pressure transient analysis.

In the early 2000’s the initial bubble of excitement about PDG data burst quickly: the data stored in the historians were huge. If engineers could find the data in the first place, it ground their computers to a halt, often ending with the ‘blue screen of death’.

Work at Stanford University produced smart, wavelet based filters that drastically reduce the number of points without eroding the data signature.

KAPPA initially released a stand-alone application (Diamant) to perform this task and subsequently developed this to an asset-wide shared environment accessing multiple data sources.

Today Diamant Master is a client-server solution that loads, processes and shares standardized data within a workgroup and establishes real-time links with Intelligent Fields.

Pressures and temperatures are processed using wavelets. Definition of rates, previously requiring heavy manual intervention to correct inaccurate reallocation processes, is solved with a new algorithm that identifies shut-ins with a high and useable level of reliability.

This missing link in automating the process of creating build-up files in the intelligent field environment is detailed below.

One of the ways to enhance the workflow is to avoid duplication. Whenever possible Diamant Master and the Ecrin modules will share and/or transfer data and technical objects. Any dynamic data acquired and filtered by Diamant Master is immediately accessible to the relevant Ecrin modules. One can also drag-anddrop data loaded by an Ecrin module into Diamant Master, making this data available to all workgroup users with the right privilege, or to another Ecrin module, to a different document from the same module, or within the same document.

The same ease of manipulation applies to technical objects such as PVT, reservoir maps, relative permeability tables, intake curves, IPR’s, analytical models and numerical models.

PVT objects may be tables, black oil correlations or an EOS. In some environments (Saphir NL, Topaze NL, Rubis) this PVT may be isothermal. In other modules (Emeraude, Amethyste, Rubis) temperature dependency may be required. When dragged and dropped from an environment to another a PVT object will adapt and request what it takes to switch from isothermal to non-isothermal, or vice versa.

Analytical models may be exchanged between Saphir NL and Topaze NL. It is actually possible to convert a whole document, with information, data and models, from PTA to PA or vice versa.

Numerical models may be exchanged between Saphir NL, Topaze NL and Rubis. The gridding will dynamically adapt to its new use and environment. Numerical models are of increasing importance, especially in the context of unconventional resources.

IPR’s may be created in Saphir NL and transferred to Amethyste, or the opposite. Well intake curves and well models calculated by Amethyste can be sent to and used by Saphir NL, Topaze NL and Rubis.

Sharing data and technical objects goes beyond KAPPA applications. Diamant Master already has plug-ins to connect to Intelligent Field models and third party databases. In its next generation Diamant Master will also offer OpenServer APIs for third party applications to retrieve data and Ecrin analyses.

With Ecrin we seek, step by step, to build an understanding of the reservoir and its wells from the various dynamic data available. First we use the data for analysis, then we use the result to history match all available data. Finally we want to forecast the future. One way or another we need to feed a unique model, which we will use as a proxy of the reservoir.

One such a proxy could be the geological model. But this will seldom work and, arguably, even when it does, there is generally no time to use and update it in a practical sense. At the other end of the scale an alternative might be to use simple proxies such as decline curves or analytical models, but these are an over simplification and not up to the increasing complexity of drive mechanisms.

KAPPA’s position is that such a proxy has to be an intermediate numerical model between a single tank material balance and the upscaled geological model. Such a proxy should be complex enough to reproduce the main reservoir drives, but simple enough to allow shorter, practical work cycles and above all that it must honor the dynamic data.

This numerical model also needs to ‘talk’ to each analysis module, to allow corroboration between the various methods and data sources. This is where the specific nature of the numerical tools shared by Saphir NL, Topaze NL and Rubis can be a game changer.

This original specification of Rubis was and remains diametrically opposite to the development of the next generation of zillion cell simulators with massive parallel processing. The solution is as simple as is necessary to solve the problem... but not simpler.

When the first numerical model was released in Saphir the relatively simple objective was to simulate linear diffusion problems for geometries too complex for analytical tools. It used the unstructured Voronoi grid and could generate models on a logarithmic time scale with a speed and accuracy comparable to an analytical model. This allowed interpretations to be achieved within the time frame usually allocated to making a transient or production analysis.

Gridding was of limited concern to the engineer who could therefore focus on the real issue of the physical problem. The sequence starting on the right shows the typical steps in building a 2D numerical model.

The starting point of an interactive build will be a scaled bitmap representing the reservoir, its main inner boundaries and its wells (1).

From this bitmap the user interactively builds a vector representation of the problem, including the reservoir outer contour, the inner faults and the wells (2). Composite zones (3) and thickness / porosity / permeability fields (4) may also be defined.

Ecrin then builds the grid automatically (5)!

After simulation, the static and dynamic properties can be visualized and animated in 2D using a color lookup table (6), in pseudo-3D where the Z axis represents one property and the color coding may represent another property (7), and in standard 3D (8).

Around each well, the 2D unstructured grid is replaced by a 3D unstructured grid whenever needed, as in the case of a limited entry well (9) or a horizontal well (14). These models also account for vertical and horizontal anisotropy (10).

In Rubis models different horizons and gravity can be considered. In later releases, horizons, volumes and static properties can be directly imported from Geomodelers such as Petrel™ using GRDECL or CMG formats (11).

It was natural progression to start solving nonlinear (NL) PTA and PA problems that had been hitherto overlooked. Saphir NL, Topaze NL and Rubis can be used to model real gas diffusion, multiphase flow, water and gas injectors, water drives, nonDarcy flow (Forscheimer), unconsolidated formations and desorption models for unconventional resources.

All Ecrin numerical modules use the same technical kernel and the same basic reservoir grids (12), but with a flexible upscaling adapted to their very different requirements around the well.

Considering the case of a horizontal well, Saphir NL needs very significant refinement, with around two thousand cells to perfectly simulate the different 3D flow regimes on a loglog scale (13). Topaze NL will only require a detailed 2D or limited 3D representation with around 300 cells around the well (14). Rubis time steps being days or weeks a very coarse grid with only six cells is suitable (15).

Comparing these three different refinements on a loglog scale shows that all responses merge on a reference analytical model after a time adapted to the required minimum time steps (16).

We have a trick: rather than using an analytical well index, before any run coarse grids are calibrated with a refined PTA grid with a small single phase simulation around each well. The value of the coarse grid well index is adjusted to match the long term productivity of the refined grid. Numerical problems can therefore be transferred between modules, upscaled or downscaled, and they will remain consistent.