gplately.ridge_spreading_rate

gplately.ridge_spreading_rate(rotation_features_or_model, topology_features, time, threshold_sampling_distance_radians, spreading_feature_types=[<pygplates.pygplates.FeatureType object>], transform_segment_deviation_in_radians=1.2217304763960306, velocity_delta_time=1.0, anchor_plate_id=None, include_network_boundaries=False, output_obliquity_and_normal_and_left_right_plates=False)

Calculate spreading rate of ridge segments (and other statistics like spreading obqliquity, and ridge length/normals and left/right plates).

The transform segments of spreading features are ignored (unless transform_segment_deviation_in_radians is None).

Resolves topologies at time, tessellates all resolved spreading features to within threshold_sampling_distance_radians radians and returns a list of tuples where each tuple represents a tessellated point.

Parameters:

  • rotation_features_or_model (str/os.PathLike, or pygplates.FeatureCollection, or pygplates.Feature, or sequence of pygplates.Feature, or a sequence (eg, a list or tuple) of any combination of those four types, or pygplates.RotationModel) – A rotation model to calculate spreading rate. Can be provided as a rotation filename, or rotation feature collection, or rotation feature, or sequence of rotation features, or a sequence (eg, a list or tuple) of any combination of those four types.

  • topology_features (str/os.PathLike, or pygplates.FeatureCollection, or pygplates.Feature, or a sequence pygplates.Feature, or a sequence (eg, a list or tuple) of any combination of those four types) – Reconstructable topological features representing the spreading features.

  • time (float) – The reconstruction time (Ma) at which to calculate spreading rate.

  • threshold_sampling_distance_radians (float) – Threshold sampling distance along spreading features (in radians).

  • spreading_feature_types (pygplates.FeatureType or sequence of pygplates.FeatureType, default=pygplates.FeatureType.gpml_mid_ocean_ridge) – Only spreading features with a feature type contained in this list are considered. If None then all spreading features are considered.

  • transform_segment_deviation_in_radians (float, default=<implementation-defined>) – How much a segment can deviate from the stage pole before it’s considered a transform segment (in radians). The default value has been empirically determined to give the best results for typical models. If None then the full feature geometry is used (ie, it is not split into ridge and transform segments, with the transform segments getting ignored).

  • velocity_delta_time (float, default=1.0) – Delta time interval used to calculate spreading velocity. Defaults to 1 Myr.

  • anchor_plate_id (int, optional) – Anchor plate ID for reconstruction. If not specified then uses the default anchor plate of rotation_model if it’s a pygplates.RotationModel (otherwise uses zero).

  • include_network_boundaries (bool, default=False) – Whether to calculate spreading rate along network boundaries that are not also plate boundaries (defaults to False). If a deforming network shares a boundary with a plate then it’ll get included regardless of this option.

  • output_obliquity_and_normal_and_left_right_plates (bool, default=False) – Whether to also return spreading obliquity, normal azimuth and left/right plates.

Returns:

output_data – The results for all tessellated points sampled along spreading features. The size of the returned list is equal to the number of tessellated points. Each tuple in the list corresponds to a tessellated point and has the following tuple items (depending on output_obliquity_and_normal_and_left_right_plates):

If output_obliquity_and_normal_and_left_right_plates is False (the default):

  • longitude of tessellated point

  • latitude of tessellated point

  • spreading velocity magnitude (in cm/yr)

  • length of arc segment (in degrees) that tessellated point is on

If output_obliquity_and_normal_and_left_right_plates is True:

  • longitude of tessellated point

  • latitude of tessellated point

  • spreading velocity magnitude (in cm/yr)

  • spreading obliquity in degrees (deviation from normal line in range 0 to 90 degrees)

  • length of arc segment (in degrees) that tessellated point is on

  • azimuth of vector normal to the arc segment in degrees (clockwise starting at North, ie, 0 to 360 degrees)

  • left plate ID

  • right plate ID

Return type:

a list of tuples