IN-SITU STRESS FIELD AND GEOLOGICAL TECTONIC ANALYSIS AT HUANGDAO WATER-SEALED UNDERGROUND OIL CARVEN SITE

The initial in-situ stress field has significant influence on the stability of surrounding rock of underground carven. Nevertheless, the in-situ stress field result obtained by a single method is usually not of high reliability because of the complexity of geological conditions. This paper takes the Huangdao underground water-sealed cavern as example and analyzes its regional tectonic background and near-field faults. The in-situ stress field is tested by hydraulic fracturing method. The maximum principal stress is obtained. Its directions are is mainly oriented NWW.Its advantage direction is N73W. The stress field of study area is analyzed by geological structure analysis method. The impact of regional tectonic history on present tectonic stress field of study area is discussed. It is found that the maximum principal stress direction is NW～NNW.The maximum principal stress directions obtained by construction analysis and hydraulic fracturing method are roughly NW.But there is a certain bias. The main reason is probably due to the fact that the geological structure of research area is complicated and affected by the boundary conditions of tectonic deformation. Thus, the derived local stress field is deflected. The results suggest that the comprehensive evaluation of regional geological structure analysis and in-situ stress test should be used for stress field analysis. The result has a certain reference value for the comprehensive determination of stress field.