Hello everyone,
I’m trying to model the flexure of the Juan Fernández Ridge using the GMT command grdflexure. Specifically, I am working on a section between Alejandro Selkirk Island and Robinson Crusoe Island.
However, I am having trouble interpreting the results produced by grdflexure The outputs seem unrealistic for the submarine seamounts located in this area. When I check the grids with grdinfo, some of the resulting values appear physically unreasonable for the expected flexural response.
I would also appreciate clarification about the difference between the -W and -Z options in grdflexure, since I am not completely sure when each one should be used and how they affect the final solution.
I’m attaching the code and figures below in case someone can help me identify what I might be doing wrong or suggest parameters/settings that I should revise.
Any help would be greatly appreciated!
#!/usr/bin/env bash
bati=../mallas/Hybrid_DJF_2.grd
Te6=16k #olivares 2025
rho_w=1035 #densidad agua de mar
rho_m=3330 #densidad del manto
rho_c=2800 #densidad de la carga
prof=3800 #profundidad media del fondo
#simulación
gmt grdflexure $bati -Gpruebacodigo.grd -D$rho_m/$rho_c/$rho_c/$rho_w -E$Te6 -W$prof -Z$prof -fg -V
pruebacodigo.grd: Title: Produced by grdflexure
pruebacodigo.grd: Command: gmt grdflexure ../mallas/Hybrid_DJF_2.grd -Gpruebacodigo.grd -D3330/2800/2800/1035 -E16k -W3800 -Z3800 -fg -V
pruebacodigo.grd: Remark:
pruebacodigo.grd: Gridline node registration used \[Geographic grid\]
pruebacodigo.grd: Grid file format: nf = GMT netCDF format (32-bit float), CF-1.7
pruebacodigo.grd: x_min: -81 x_max: -79 x_inc: 0.000277777777778 (1 sec) name: longitude n_columns: 7201
pruebacodigo.grd: y_min: -36 y_max: -31 y_inc: 0.000277777777778 (1 sec) name: latitude n_rows: 18001
pruebacodigo.grd: v_min: 6533.52246094 v_max: 8864.48242188 name: z
pruebacodigo.grd: scale_factor: 1 add_offset: 0
pruebacodigo.grd: format: netCDF-4 chunk_size: 129,129 shuffle: on deflation_level: 3
pruebacodigo.grd: Default CPT:
We also noticed that in some of the examples from the documentation, when we try to submerge the generated seamount, the output values increase dramatically as well.
echo 300 300 0 40 40 5000 | gmt grdseamount -R0/600/0/600+uk -I1000 -Gsmt.nc -Dk -E -F0.1 -Cg -V
grdseamount [INFORMATION]: Reading Data Table from Standard Input stream
grdseamount [INFORMATION]: Seamount 1 [g] area, volume, mean height: 5.02655e+09 5.83638e+12 1161.11
grdseamount [INFORMATION]: Cartesian input grid
grdseamount [INFORMATION]: Cartesian input grid
grdseamount [INFORMATION]: Evaluate seamount # 0 [g]
grdseamount [INFORMATION]: Writing grid to file smt.nc
gmt grdflexure smt.nc -Gflex.nc -E10k -D3300/2700/1035 -V
gmt grdinfo flex.nc
flex.nc: Title: Produced by grdflexure
flex.nc: Command: gmt grdflexure smt.nc -Gflex.nc -E10k -D3300/2700/1035 -V
flex.nc: Remark:
flex.nc: Gridline node registration used [Cartesian grid]
flex.nc: Grid file format: nf = GMT netCDF format (32-bit float), CF-1.7
flex.nc: x_min: 0 x_max: 600000 x_inc: 1000 name: x n_columns: 601
flex.nc: y_min: 0 y_max: 600000 y_inc: 1000 name: y n_rows: 601
flex.nc: v_min: -1650.26965332 v_max: 25.5098819733 name: z
flex.nc: scale_factor: 1 add_offset: 0
flex.nc: format: netCDF-4 chunk_size: 151,151 shuffle: on deflation_level: 3
flex.nc: Default CPT:
##########################################################################################
echo 300 300 0 40 40 5000 | gmt grdseamount -R0/600/0/600+uk -I1000 -Gsmt.nc -Dk -E -F0.1 -Cg -Z-6000 -V
grdseamount [INFORMATION]: Reading Data Table from Standard Input stream
grdseamount [INFORMATION]: Seamount 1 [g] area, volume, mean height: 5.02655e+09 5.83638e+12 1161.11
grdseamount [INFORMATION]: Cartesian input grid
grdseamount [INFORMATION]: Cartesian input grid
grdseamount [INFORMATION]: Evaluate seamount # 0 [g]000
grdseamount [INFORMATION]: Writing grid to file smt.nc
gmt grdflexure smt.nc -Gflex.nc -E10k -D3300/2700/1035 -W6000 -V
gmt grdinfo flex.nc
flex.nc: Title: Produced by grdflexure
flex.nc: Command: gmt grdflexure smt.nc -Gflex.nc -E10k -D3300/2700/1035 -W6000 -V
flex.nc: Remark:
flex.nc: Gridline node registration used [Cartesian grid]
flex.nc: Grid file format: nf = GMT netCDF format (32-bit float), CF-1.7
flex.nc: x_min: 0 x_max: 600000 x_inc: 1000 name: x n_columns: 601
flex.nc: y_min: 0 y_max: 600000 y_inc: 1000 name: y n_rows: 601
flex.nc: v_min: 10963.7597656 v_max: 16956.2636719 name: z
flex.nc: scale_factor: 1 add_offset: 0
flex.nc: format: netCDF-4 chunk_size: 151,151 shuffle: on deflation_level: 3
flex.nc: Default CPT: