Borehole data obtained during a drilling process can greatly improve the understanding of evolving reservoir characteristics and conditions. Drilling logs and sensor data such as gamma ray, resistivity, and dipmeter can provide engineers with a wealth of additional geologic detail associated with a borehole. When newly-acquired borehole datasets are combined with existing reservoir data, then analyzed and visualized in 3D, management teams gain better insight into reservoir potential and performance. The added insight promotes better planning and execution of reservoir development and operations.
Borehole data analysis benefits both drilling engineers and reservoir engineers. Drilling engineers can compare existing earth models against well log data and, when necessary, make real-time adjustments to drilling strategy, wellpath direction, and completion methods to minimize risk while maximizing recovery potential. Reservoir engineers can combine new borehole datasets with an existing geologic model and apply interpolation algorithms to gain a more current understanding of current reservoir characteristics.
By applying a variety of interpolation techniques to borehole datasets, engineers achieve a better representation of reservoir characteristics, beginning with detailed digital models of individual wells and extending to digital models that characterize an entire reservoir.
Borehole Data Analysis: The Drilling Engineer’s Perspective
Borehole data analysis enables drilling engineers to compare actual petrophysical data such as mud logs, gamma ray, temperature, and pressure with the predicted data obtained from previous seismic surveys and reservoir simulations. Data from a new borehole can confirm current models regarding lithology, permeability, and porosity, or reveal variations or discontinuities in the reservoir. In the event of notable differences, engineers can modify their drilling strategy to optimize borehole location and completion methods.
Near real-time WITSML drill string data can be incorporated into an existing 3D earth model to visualize the drilling progress and borehole location in context of the surrounding geology and nearby wells. For example, when a fault is encountered, visualizing the borehole location relative to subsurface structures can help determine the appropriate drilling trajectory.
Data acquisition technologies are enabling drilling engineers to create a detailed, digital borehole model incorporating more than a dozen petrophysical data types combined with details regarding location, casings, cementing, perforations, and production metrics. With detailed models of individual boreholes and relevant information that provides a history of well development, drilling engineers can analyze and compare borehole data to identify attributes that contribute to or detract from optimal development and production.
Borehole Data Analysis: The Reservoir Engineer’s Perspective
The data obtained from newly-completed boreholes can also be used to refine existing geological, geophysical, and petrophysical models. Interpolation techniques can be applied to newly-obtained borehole data to calculate reservoir characteristics such as lithofacies distributions and sandstone permeability between boreholes. Back-interpolation of reservoir properties between spatially overlapping data can also facilitate a comparison of seismic fault data with similar data obtained from well logs.
By combining existing geologic models with newly-generated borehole datasets, reservoir engineers obtain a better understanding of the petrophysical properties, depositional environment, and reservoir geometry. More accurate reservoir models enhance every aspect of reservoir management, from updating production decline curves to the development of drilling and completion plans based on the performance of existing wells.
Maximize the Inherent Value of Borehole Data with CoViz 4D
Reservoir teams can obtain the maximum value from borehole data with the aid of CoViz 4D which integrates, analyzes, and visualizes diverse spatial and temporal datasets. CoViz 4D offers powerful capabilities to capture relevant borehole data, visualize it within the context of geologic, geophysical, and reservoir data, and interpolate newly-acquired borehole data using existing geologic models to generate a more accurate model of current reservoir characteristics.
CoViz 4D can accelerate decision time and improve decision quality related to borehole planning and drilling.
Enhanced borehole data analysis benefits both conventional and unconventional projects but is particularly beneficial for unconventionals where profit margins are thin and careful analysis of factors such as well costs, completion designs, and frac designs are critical in determining economic viability. CoViz 4D can accelerate decision time and improve decision quality related to borehole planning and drilling. And as additional borehole data are acquired, geological, geophysical, and petrophysical models are updated to more accurately depict current reservoir characteristics.