The demand for environmental and economic sustainability has encouraged industries to approach new techniques of energy development. The hydrocarbon sector is increasingly looking at the mature and depleted oil fields that meet the temperature requirement for any potential of geothermal energy extraction. These mature hydrocarbon fields already have existing infrastructure and relevant data, while some may even have a large amount of formation water in the reservoir. To understand the geothermal possibility, the available geothermal and engineering data can be integrated and visualized as a 3D model.
The ability to look at all the data as a 3D model in a single geospatial environment helps industries to assess the viability of the geothermal energy at that location while significantly reducing the operation cost.
Pre-Existing Advantages of Mature Oil Fields
While the use of mature or abandoned oil fields sounds promising, not all have the potential for geothermal exploitation. Oil fields mostly have lower-temperatures than geothermal fields. A sufficient enough temperature needs to be evaluated in such reservoirs to consider harnessing geothermal energy. In mature oil fields, geothermal prospectors further look for significant advantages such as:
- Pre-existing geological and engineering subsurface data. The data regarding the geologic structure, rock properties, fluid production volumes, and seismic properties of the subsurface collected during the hydrocarbon exploration can serve as an asset while analyzing a mature oil field geothermal potential.
- Existing wellbores. In a mature oil field, an existing wellbore can play a significant cost-saving role given that the wellbore is in a sound condition and is drilled in the right location and deep enough to extract enough heat.
- Existing common infrastructures. Another potential advantage a mature oil field can provide for geothermal exploration is the availability of existing pipelines, power transmission lines, and access roads, which can equate to savings on development costs.
Geothermal potential analysis can incorporate all existing surface, subsurface, infrastructure, and production information into a 3D model to help illustrate the economic viability of a mature or abandoned oil and gas field.
Visualizing the Data Involved
There is no doubt that mature oil fields are data-rich and the existing well logs provide an invaluable advantage. Although additional data may be required to understand the full geothermal potential of the field.
- With new well log data, the capability of the geologic setting and wellbore infrastructure to safely handle higher temperatures and pressures can be analyzed.
- With gravity data, it is easier to delineate the higher temperature zones in the field.
- Flow tests in the old or abandoned wells visualize the temperature and pressure, injection rates, leakage, and availability of nearby wells for production.
For initial analysis, however, the ability to bring all the existing multi-disciplinary data and models together enhances the understanding of the oil field and its geothermal production potential. With the review of existing temperature logs and heat flow patterns, engineers are able to determine the optimal geothermal pay zone or determine the alternate high-temperature zone. For low-temperature reservoirs, engineers can analyze the pay-off from producing energy at a local level.
An effective 3D model further enhances the analysis by allowing side-by-side visualization and comparison of data in a single geospatial environment. Softwares like CoViz 4D and EarthVision facilitate the efficient combination of the wide range of data for 3D modeling of the subsurface in their correct geospatial location.
CoViz 4D and EarthVision: Visualize Mature Oil Fields’ Geothermal Potential
CoViz 4D and EarthVision by Dynamic Graphics, Inc. are ideally suited to the visualization and analysis of older oil fields and reservoir data for analyzing the potential geothermal opportunity. CoViz 4D, specifically, allows for the integration of various pre-existing surface and sub-surface data from the oil field to create an effective 3D reservoir simulation. The 3D model allows engineers and geoscientists the observe the geothermal gradient along the depth of the subsurface, assisting them in making decisions on additional wells and re-injection requirements for energy generation. The ability to visualize allows geoscientists and engineers to access the economic viability of mature oil fields for geothermal energy production.