DISCUSSION ON TECHNICAL PROBLEMS RELATED TO MEASUREMENT OF EARTH STRESS THROUGH HYDRAULIC FRACTURING

The scale of the minimal horizontal earth stress and the direction of the earth stress can be obtained from hydraulic fracturing. The value of the minimal horizontal earth stress equals approximately to the closure pressure of fracture formed through hydraulic fracturing. Yet, owing to the existence of the casing, the maximal horizontal earth stress can not be calculated from fracturing data of casing well. lf earth stress is tested in the course of drilling, the earth stress data can be obtained at the early stage of exploration,which is very helpful to the direction of the later exploration and development. This paper analyzes the factors influencing the accuracy of measuring the earth stress:the tested formation, the applied instruments, the operation plan, the analysis to the operatlng curves and so on. Further more, this paper puts forward proposals on how to further conduct well earth stress measurement.