Check for existing data before trying to plot to avoid warnings

u4py/plotting/plots.py

@@ -670,6 +670,7 @@ def geology_map(
                 suffix=f"_{row[1].group:05}",
                 out_folder=shp_path,
             )
+        if fault_data:
             fault_data.plot(ax=ax, color="k")
 
         # Formatting and other stuff