As part of drilling operations, geological and petrophysical information about subsurface formation is required to evaluate a reservoir. After samples of reservoir rock (core samples) have been collected, a detailed analysis and study is conducted to understand a number of reservoir characteristics, such as reservoir porosity (fluid-carrying capacity), permeability (ability of fluids to flow), hydrocarbon and water saturation and many more. Analyzing cores can take up to 2 years and requires a multidisciplinary skills set and experience, to provide accurate and detailed results.
Having this analysis, understanding and knowing reservoir properties is key to estimate hydrocarbon production and how variation in these properties will affect production and ultimate recovery.
Core analysis consist of Routine Core Analysis and Special Core Analysis (SCAL)
Routine Core Analysis
- Permeability (horizontal and vertical)
- Grain density
- Fluid saturation
- Lithological description
- Gamma log
Special Core Analysis (SCAL)
SCAL or SPCAN is a process of measuring and evaluating cores with mode advanced experiments, such as Electrical Properties, Capillary Pressure, Wettability and Flow Tests. The process differs from lab to lab, hence ensuring that data from each lab is consistent in vital. SCAL is a very subjective process, as such a third party expertise and recommendation is required to ensure that the interpretation of cores is accurate and unbiased. API RP40 document provides recommended practices for SCAL.
Supply & Demand Dynamics
Demand for core analysis is driven by exploration and appraisal activities around the world and to a small extent by field re-development. Around 95% of core analysis services are required during exploration and appraisal activities. Due to limited exploration activities in GCC, current oil price environment and preference to brownfield projects, core analysis would show very limited growth opportunities. In addition, GCC represents the smallest proportion in this segment, due to major discoveries being made in the last century.
Supply of core analysis services includes personnel and laboratory equipment. As a result of complexity of core analysis, knowledge of reservoirs and laboratory QA/QC procedures are of utmost importance to ensure accurate and detailed analysis. Due to cyclical nature of this segment, service providers try to keep capacities balanced and in times of high demand there is always a significant lead-time book a slot for analysis. In addition, most of the core laboratories providing the services are diversified into reservoir management and fluids analysis, to offset the highly cyclical nature of this segment, driven by exploration / appraisal activities and oil price.
Intertek, Core Lab and Kirk Petrophysics (ALS) have been market leaders for years. There are a number of other players available with various specialized expertise and geographic locations.
Total Cost of Ownership
Experience, track record and reputation of a core analysis laboratory, probably the most important factor and far outweighs the costs.