摘要
实测的浅层地温受地表温度周期性日变和年变的影响 ,使得正常浅层地温发生畸变。为了改正其影响 ,对实测的离散温度数据进行离散富里叶变换 ,将地表温度转化为富里叶级数形式 ,可以得到富里叶振幅谱和相位谱 ,进而获得地表温度变化对地下温度场的影响深度和程度的数学表达式。地表温度变化周期长 ,且地下介质热扩散率大 ,则地温受影响的深度和程度大 ;反之则小。
As geotemperature at the shallow layer is affected by daily and yearly periodic change of temperature on the earth′s surface, the normal geotemperature is likely to be distorted. To eliminate this effect, the authors transformedactual measuring discrete temperature data into Fourier form and got Fourier frequency and phase spectra. On such a basis, the mathematical expression for thedegree and the depth of the influence of the earth′s surface temperature was formulated in terms of amplitude. The longer the periodic variation of temperatureon the earth′s surface and the bigger the thermal diffusivity of the media, thegreater the depth and the degree of the influence.
出处
《地球学报》
EI
CAS
CSCD
北大核心
2004年第5期579-582,共4页
Acta Geoscientica Sinica
基金
中国地质调查局"大面积地温调查方法预研究"(项目编号 :2 0 0 12 0 12 0 0 85 )项目资助。
关键词
气候变化
浅层地温测量
富里叶级数
振幅
climatic change shallow layer geotemperature Fourier series amplitude period
