Investigation of Fracture Conductivity Under In Situ Conditions as a Function of Frac- and Formation Parameters
Because of their low permeability, deep-lying gas fields are often developed by the fracturing technique. Essential for the economy of this measure is a high fracture conductivity which persists over a long period.
The objective of the project was the investigation of the various factors influencing the fracture conductivity under reservoir conditions. Besides the breaking strength of proppants, which is decisive for the conductivity attainable at high confining pressure, the long-term stability, the embedment and the transport of fragments, which results in plugging, were examined.
With the proppants Superprop and Carboprop HC, fracture conductivity exhibits only a slight dependence on the closure pressure. Transport of fragments and embedment play no important role. With resin-coated proppants, conductivity is not improved appreciably. The resin-coating doesn’t resist reservoir conditions. After only one week, aquathermolytic products were detected.