Minecraft wiki entry for Custom_world_generation, associated text:  config: Configuration values for the carver.
 vertical_rotation:[needs testing] Creates the curves in the canyon as it continues.
Float provider[show]
 shape: The shape to use for the ravine.
 thickness:[needs testing] The width of the canyon.
Float provider[show]
 width_smoothness:[needs testing] Higher values seem to smooth canyon walls on the vertical axis. Must be positive.
 distance_factor:[needs testing]
Float provider[show]
 horizontal_radius_factor:[needs testing]
Float provider[show]
 vertical_radius_default_factor:[needs testing]
Float provider[show]
 vertical_radius_center_factor:[needs testing]
Float provider[show]