Data Quality of In-Situ Stresses by Hydraulic Fracturing Method

Applicability of High-Compliance System and Evaluation of Maximum Stress Based on the Results in Granite

Abstract

Japan Atomic Energy Agency has been conducting in-situ stress measurements by hydraulic fracturing method to aiming establish a firm scientific basis for safe geological disposal. Hydraulic fracturing method has many results, but including many errors in data as International Society for Rock Mechanics suggested. This report describes results compared with the data obtained by ordinary system and that of new type of system. Based on the results of 57 hydraulic fracturing tests in Granite at the maximum depth of 1000m, rate of low-quality data obtained by ordinary system was 35%. The quality of data obtained by new type of system improved comparing with the ordinary system, as data of flow rate was measures in borehole. Maximum horizontal stresses calculated using ordinary equation overestimate about 23%.