温度是影响岩石孔隙流体核磁共振弛豫的因素之。选取一组饱和水的人造碳化硅、人造碳酸钙、储层贝瑞砂岩以及碳酸盐岩样品进行核磁共振实验(温度25~90℃),考察温度对弛豫速率的影响。结果表明,对于饱和水的砂岩和碳酸盐岩,温度对岩石核磁共振表面弛豫的影响不同。饱和水的人造碳化硅和储层贝瑞砂岩的核磁共振弛豫速率随温度升高而增大;饱和水的人造碳酸钙和储层碳酸盐岩的弛豫速率随温度升高而减小。因此,在利用室温下得到的实验测量结果对储层温度下的核磁共振测井数据进行刻度时,应考虑温度的影响。
Temperature is one of the factors which affect nuclear spin-relaxation in rocks. A series of water-saturated core samples including silica carbide, calcium carbonate, Berea sandstone and reservoir carbonate were selected to measure nuclear spin-relaxation from 25 ℃ to 90 ℃. The results show that temperature effects on nuclear magnetic resonance(NMR) surface relaxation between water-saturated sandstone and carbonate are different. The nuclear spin-relaxation rate( 1/T2 ) increases with temperature increasing for water-saturated silica carbide and reservoir Berea sandstone. Relaxation rate decreases with temperature increasing fnr water-saturated calcium carbonate and reservoir carbonate. The temperature effect should be taken into account while calibrating NMR logging data by using laboratory experiments performed at room temperature.