Surfer can import and export Esri floating point grid files in Esri Spatial Analyst .FLT, .HDR format.
The Esri Binary Float Grid format consists of 2 files: a binary .FLT image file and ASCII .HDR header file with the same file name but different file extension. For example, Test.FLT and Test.HDR.
Loading .FLT Files
Esri Float Grid .FLT files can be loaded to create a grid based map (i.e. Home | New Map | Contour) with the Open Grid dialog, or when using the functions in the Grid menu.
Import Options Dialog
No import options dialog is displayed.
Import Automation Options
No import options are available.
Use the Grids | Edit | Convert command in the plot document, or File | Save As in the Grid Editor to export .FLT files. Alternatively, the Esri .FLT file format is available when prompted to save a grid file.
Export Options Dialog
When the input grid is georeferenced, see Spatial References. By default, an Esri .PRJ file is created automatically when exporting this Esri file type.
Export Automation Options