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

A novel method to map and quantitatively describe very gentle folds (limb dip <5°) at cratonic cave sites was evaluated Snail Shell Nanna caves, central Tennessee, USA. Elevations from the global SRTM digital terrain model (DTM) were assigned points on late Ordovician geologic contacts, elevations of used interpolate 28 m cell size natural neighbor elevation models (DEM’s) contacts. The Forest Canopy Height Dataset subtracted AW3D30 surface (DSM) create a DTM, that DTM applied in same way. Comparison mean modal strikes interpolated surfaces with passage trend shows many passages are sub-parallel an anticline. WithiSn 500 SRTM- AW3D30-based have within 8° strike reference created high resolution (~0.76 10 cm RMSE) USA LiDAR DTM. This evaluation has potential reveal relationship between fold, one hand, passages, other, where contact varies by >35 area <12.4 km2 bedding is >0.9°.