Mini-frac / DFIT

A critical component of determining caprock integrity is the determination of in-situ stresses. Mini-fracs and DFIT’s are common and reliable techniques for indirectly measuring the formation’s minimum in-situ stress. During a mini-frac, test fluid is pumped in a short pulse into the reservoir to create a small fracture that cuts through near- wellbore damage to establish communication with the true formation.

Hydraulic fractures naturally follow the path of least resistance, thus propagating perpendicular to the formation’s minimum principal stress. After the fracture is opened, the pumps are shut down. As the downhole pressure declines, test fluid leaks off into the formation and the induced fracture closes. This pressure decline can be analyzed to determine when the fracture closes. The pressure at which a hydraulic fracture closes is equivalent to in-situ stress of the formation.

To detect when the fracture closure occurs, BGES believes that a single unique closure event should satisfy multiple diagnostic plots or methods. Therefore, a combination of analytical methods are used in concert to arrive at a consistent interpretation of fracture closure. This is also known as the “holistic fracture diagnostics” methodology.

Applications

SAGD, CSS, Water/polymer flood operations, where the Caprock’s minimum in-situ stress governs the maximum operating injection pressure to avoid fracturing the Caprock.
Shale oil/gas production – for fracture treatment design.

Features & Benefits

A mini-frac (or DFIT) is a cost-effective and reliable method to determine the formations’ minimum in-situ stress.
Via satellite systems, test data can be viewed in real-time through the internet as it is acquired in the field. A real-time closure confirmation is conducted before ending a test, ensuring that useful data is obtained.
BGES provides detailed engineering analyses on the data collected, with a transparent interpretation of test results in a comprehensive regulatory report to ensure the customer’s regulatory application is efficient and seamless.

Operations

Steady and constant injection of test fluid is accomplished through the use of our advanced DCS-controlled injection unit. In order to ensure the accuracy and quality of data obtained, multiple points of high-precision measurements are taken at the wellhead and downhole with backups.Test data can be monitored through satellite from anywhere in real-time.