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Abstract The relative stress field was analyzed through a series of continuous observed borehole stress-strain data in Xinjiang region. The results show that the direction of principal compression in terms of relative field is orientated mainly in NS direction but has the feature of regional distribution. In the middle and western sections of the West Kunlun mountain it shows in the NS direction，while in the East Kunlun mountain it exhibits in the NNE direction. In the North Tianshan mountains and the Tarim Basin it also indicates in the NNE direction. In the west part of South Tianshan it ordinates in the NW direction；and while in the east part of south Tianshan mountains it is in the NE direction. The results further indicate that both the compression and shearing stresses are large but weak for tensile stress. The magnitude of stress tends to reduce from the west to the east and weak from the south to the north. For the magnitude of both the principal compression and the shearing stress the largest ones are dominant in the Kashi region，where the Pamir arc and the Tianshan mountain is intersected. For the magnitude of the principal tensile stress the largest one is observed in Shihezi region of the North Tianshan and the smallest one is exhibited in Urumqi region. Meanwhile，the difference of the stress variation is large and shows a nonuniform distribution. The angle between the direction of principal compression and the regional tectonic trend and the mountain extended line is large，which indicates that the tectonic and mountain in Xinjiang region is subjected to the action of compression force，which is perpendicular to the above tectonic lines.
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Received: 30 June 2011
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2012, Vol. 31 
