BGES offers a full suite of geomechanical testing and analysis for caprock integrity assessments. Test programs are designed to evaluate key properties including compressive, tensile and shear strengths, Young’s modulus, and permeability. Lab test data can be correlated and combined with other information collected, for example mini-frac results and logs, to confirm the caprock’s physical properties.

Triaxial analysis involves placing the test specimen in a pressure cell to simulate underground conditions. By applying loads, we determine physical properties and shear strength until failure. At BGES, our proprietary lab process includes meticulous core sample preparation and setup to replicate real oilfield conditions. Our expertise lies in testing caprock core for thermal production schemes like steam-assisted gravity drainage (SAGD) and cyclic steam stimulation (CSS), as well as subsurface storage operations like carbon capture, utilization, and storage (CCUS).

BGES operates one of the select few labs in North America to specialize in high-temperature triaxial tests, ensuring precise emulation of operational conditions for oil sands samples.

Additionally, our expertise ensures that samples are sheared appropriately, accounting for proper fluid drainage and precise pore pressure measurement. By testing full diameter cores, we obtain representative samples of heterogeneous caprocks, enabling a comprehensive evaluation of caprock integrity.

Our suite of Index tests includes the Atterberg limit index tests, which helps to determine liquid limit, plastic limit and plastic index, hydrometer analyses to determine grain size distribution, and the X-Ray Diffraction (XRD) Analyses to study the caprock’s mineralogy. Index testing combined with triaxial tests will provide better understanding of caprock integrity.

Caprock permeability plays a vital role in evaluating caprock integrity, making it a crucial parameter. It refers to the caprock’s ability to facilitate fluid flow, impacting fluid migration and containment effectiveness. In addition to standard triaxial tests, lab permeability testing is essential for evaluating the caprock’s sealing capacity. For a thermal production scheme, understanding the permeability of a caprock helps quantify steam losses and assess pore pressure changes within the caprock.

Measuring caprock permeability accurately can be challenging due to its typically low values and susceptibility to stress and temperature variations over time. At BGES, we have developed specialized permeability testing procedures tailored to thermal production and storage operations, enabling us to conduct various permeability measurements under different pore pressure and temperature conditions.

A capillary breakthrough test holds significant importance in evaluating the performance of a caprock as a barrier or upper seal. In low-permeability caprocks, the interconnected network of pores relies on interfacial tension for effective containment. Capillary pressure acts as a crucial factor in preventing the intrusion of steam, mobilized hydrocarbons, or stored fluids such as CO2 into the caprock. A caprock capillary breakthrough test enables us to determine the specific point at which capillary forces are surpassed, allowing fluid movement within and across the caprock formation. This test is part of a comprehensive assessment of caprock integrity to ensure safe and efficient operations.