trend surface與一般等高線不同在於trand surface analysis可以得到殘餘值，通常趨勢面紙能得到區域的趨勢資料，但是若把觀測值減去趨勢面得到的估計值時就會得到殘餘值，從殘餘值可以看出局部異常現象，舉例來說，殘餘值常被利用來尋找礦脈。-The the the trend surface contour difference is that the trand surface analysis can get the residual value, the usual trend of glossy paper to get the regional trend data, but will if the observed value minus the estimated value of the trend surface residual value from the residual value can seen that the local anomalies, for example, the residual value is often used to find veins.