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Abstract To ensure mining safety，in-situ stress measurement in Linglong gold mine is carried out in two periods. The first period measurement is performed in the shallow position and the second period measurement is performed in the deep position. The measurement process and results are introduced. In order to increase reliability and accuracy of the measurement，a series of new techniques including complete temperature compensation technique and improved hollow inclusion strain devices are used in the measurement. Through in-situ measurement，3D geostresses at 18 points，which are distributed in 7 levels，are determined. Based on the measuring results，comprehensive study of distributing law of the in-situ stress field in the mine is completed. Some conclusions are drawn as fallows：(1) The in-situ stress in Linglong gold mine is dominated by horizontal tectonic stress field rather than the gravity stress field. The magnitude ratio of maximum horizontal principal stress to gravity stress in the mine is 2.26 in average. (2) The maximum horizontal principal stress is oriented in NW direction which is approximately coincided with the orientation of the maximum principal stress of tectonic stress field. (3) The vertical principal stress is basically equal to or a little larger than the gravity. (4) Despite the rock nature in deep position is changed；and the distribution law of in-situ stress state is not remarkably changed in deep position compared with that in shallow position. (5) The maximum horizontal principal stress，minor horizontal principal stress and vertical principal stress are almost linearly increased with depth.
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Received: 21 August 2009
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