Acquiring coal reservoir stress parameter by hydraulic fracturing method

In-situ stress is one of important factors used to evaluate the coal reservoir.The fundamental principle of hydraulic fracturing method for measuring in-situ stress is briefly introduced in this paper.Based on three sets of typical in-situ stress data from well site, it focuses on how to acquire the closure pressure of coal reservoir by using time square root and bilogarithmic methods. The study results would be useful for coalbed gas reseachers.