地理情報学と地球統計学: 概要

Gravity Data Transformation by Polynomial Fitting and Kriging Data Analysis of the Mamfe Basin (Cameroon)

Nguimbous-Kouoh JJ, Ndougsa-Mbarga T and Manguelle-Dicoum E

Thirty-six gravity Bouguer data were collected in the Mamfe sedimentary basin. Third-order polynomial filtering was applied to the data. Third-order regional and residual gravity data were plotted as boxplots to compare distributions of different gravity fields. Boxplots enable to observe outliers in the data. These values 
allowed for a more detailed study of the observed regional and residual anomaly values as they could have a significant impact on the results. Boxplots also found that the gravity data showed asymmetry. The kriging analysis procedure was initiated to describe the spatial variability of the different gravity data. The Gaussian
theoretical model was used to test anisotropy. The anisotropy test has shown that regional and residual gravity data exhibit geometric anisotropy and that spatial continuity is not necessarily the same in all directions. The unidirectional interpolated variograms were fitted with a tolerance of between 4° and 71° and a direction between -52° and 159°. 3D wireframe maps were created to map gravity fields in three-dimensional form and evaluate interpolated surfaces.