DOI: 10.5281/zenodo.18656374
title: SAC_Head_Morphometric_Dataset_v1.0

description: SAC_Head_Morphometric_Dataset_v1.0

Description

SAC_Head_Morphometric_Dataset_v1.0 contains the consolidated morphometric parameters derived from the reproducible geometric implementation of Bührig-type metrics applied to the head of the San Antonio Submarine Canyon (SAC) system, central Chile. The implemented morphometric framework follows the definitions proposed by:

Bührig, L. H., Colombera, L., Patacci, M., Mountney, N. P., & McCaffrey, W. D. (2022). A global analysis of controls on submarine-canyon geomorphology. Earth-Science Reviews, 233, 104150. https://doi.org/10.1016/j.earscirev.2022.104150

The dataset was generated through the SAC_Head_Buhrig_Metrics reproducible computational pipeline, applied to five tributary channels forming the canyon head:





MCh (Main Channel)




SACh (San Antonio Channel)




SDCh (Santo Domingo Channel)




ECh (Emily Channel)




CCh (Cartagena Channel)



The project architecture separates regional common data (DEM and canyon-edge cartography) from channel-specific geometries (thalwegs and cleaned transverse profiles).

The Digital Elevation Model (DEM) used for all calculations was generated from bathymetric point data provided by the Servicio Hidrográfico y Oceanográfico de la Armada de Chile (SHOA). The original data were distributed in CSV format containing geographic coordinates (WGS84 latitude and longitude) and depth values. These bathymetric points were interpolated using ordinary kriging to produce a continuous bathymetric surface. The interpolated surface was subsequently reprojected to WGS 1984 UTM Zone 18 South (EPSG:32718) and stored as a 32-bit floating-point GeoTIFF raster. This DEM constitutes the three-dimensional geometric base from which all transverse and longitudinal metrics were derived.

The workflow was implemented in Python 3.12.5 under a deterministic and fully traceable computational architecture. The pipeline sequentially performs:





Extraction of key geometric points (P1–P4)




Calculation of maximum width (Wmax)




Calculation of maximum depth (Dmax)




Computation of three-dimensional lateral angles (B1, B2)




Definition of SWmax as the maximum of B1 and B2




Computation of the width-to-depth ratio (Wmax/Dmax)




Individual and batch graphical validation of all transverse profiles



Longitudinal metrics of the thalweg were also computed, including:





Real thalweg length (L, m)




Total vertical difference (Δz, m)




Average sinuosity index (SIav)




Mean longitudinal gradient (thGav, m/m)



The homogeneous application of this methodological framework to the five channels documents transverse and longitudinal geometric variability within the SAC head under a deterministic, reproducible, and Q1-standard morphometric protocol.

This dataset represents the consolidated numerical output of the pipeline documented in:

Viveros Velásquez, M. A. (2026). SAC_Head_Buhrig_Metrics (v1.0.1). Zenodo. https://doi.org/10.5281/zenodo.18645523

Viveros Velásquez, M. A. (2026). Manual for the Reproducible Geometric and Computational Implementation of Bührig-Type Metrics (Wmax, Dmax, SWmax, L, Δz, SIav, thGav): Application to the Head of the San Antonio Submarine Canyon System (v1.0). Zenodo. https://doi.org/10.5281/zenodo.18646670

and implemented in the associated GitHub repository.



Morphometric Summary Table

Head of the San Antonio Submarine Canyon System








Channel
Wmax (m)
Dmax (m)
Wmax/Dmax
B1 (°)
B2 (°)
SWmax (°)
L (m)
Δz (m)
SIav
thGav
n




MCh
8989
647
14
80
81
81
14254
376
1.19
0.03
23


SACh
2042
248
8
76
74
76
8897
318
1.55
0.04
12


SDCh
1522
178
9
76
78
78
5061
357
1.09
0.07
10


ECh
3798
399
10
76
76
76
6809
262
1.19
0.04
6


CCh
3576
275
13
78
83
83
4627
235
1.06
0.05
1








Metric Definitions

Wmax (m): Maximum transverse canyon width measured between morphological edges.Dmax (m): Maximum vertical depth between the thalweg (P1) and the horizontal reference defined by Wmax (P4).Wmax/Dmax (–): Dimensionless width-to-depth ratio describing transverse canyon shape.B1 (°): Three-dimensional internal angle of the left canyon flank.B2 (°): Three-dimensional internal angle of the right canyon flank.SWmax (°): Maximum lateral inclination, defined as max(B1, B2).L (m): Real thalweg length from apex to mouth.Δz (m): Total vertical difference along the thalweg.SIav (–): Average sinuosity index (real length divided by straight-line distance).thGav (m/m): Mean longitudinal gradient (Δz / L).n: Number of transverse profiles analyzed per channel.