Application of the global SRTM and AW3D30 digital elevation models to mapping folds at cave sites

International Journal of Speleology

卷:50

Albert Ogden¹  Mark Abolins¹ 

[1] Middle Tennessee State University;

关键词: cave map;    digital geologic map;    cratonic geology;    folds;    structural controls;    remote sensing;    spatial analysis;   

DOI  :  https://doi.org/10.5038/1827-806X.50.1.2338

来源: DOAJ

【 摘 要 】

A novel method to map and quantitatively describe very gentle folds (limb dip < 5o) at cratonic cave sites was evaluated at Snail Shell and Nanna Caves, central Tennessee, USA. Elevations from the global SRTM digital terrain model (DTM) were assigned to points on late Ordovician geologic contacts, and the elevations of the points were used to interpolate 28 m cell size natural neighbor digital elevation models (DEM’s) of the contacts. The global Forest Canopy Height Dataset was subtracted from the global 28 m cell size AW3D30 digital surface model (DSM) to create a DTM, and that DTM was applied in the same way. Comparison of mean and modal strikes of the interpolated surfaces with mean and modal cave passage trend show that many passages are sub-parallel to the trend of an anticline. Within 500 m of the caves, the SRTM- and AW3D30-based interpolated surfaces have mean strikes within 8o of the mean strike of an interpolated reference surface created with a high resolution (~0.76 m cell size and 10 cm RMSE) Tennessee, USA LiDAR DTM. This evaluation shows that the SRTM- and AW3D30-based method has the potential to reveal a relationship between the trend of a fold, on one hand, and cave passages, on the other, at sites where a geologic contact varies in elevation by > 35 m within an area of 2 and the mean dip of bedding is > 0.9o.

【 授权许可】

Unknown