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02.1 Magnitude sensitivity for homogeneous model: test case 2#
This is an example of computing magnitude sensitivity for a homogeneous model.
Test case 2:
Geometry: simple station geometry with 4 surface stations in the form of a triangle with 1 station in the center
Velocity model: homogeneous, Vp = 3100 m/s, Vp/Vs = 1.73, Qp = 70, Qs = 50, rho = 2400 kg/m^3
Processing: magnitude sensitivity computation for all stations (for grid slices only).
Load all necessary packages#
Input#
Read geometry#
geometry_file_path = '../data/homo/test_02/TMPL_net_geometryA.txt'
geometry_df = pndmod.io.read_geometry(geometry_file_path)
print(geometry_df)
print(geometry_df.attrs)
Name Y X Z NoiseLevel
0 ST1 0.0 0.0 -0.0 1.000000e-07
1 ST2 -1470.5 2547.0 -0.0 1.000000e-07
2 ST3 -1470.5 -2547.0 -0.0 1.000000e-07
3 ST4 2941.0 0.0 -0.0 1.000000e-07
{'file_path': '../data/homo/test_02/TMPL_net_geometryA.txt', 'original_coord_units': 'm', 'coordinate_system': 'local', 'noise_type': 'velocity', 'noise_unit': 'm/s', '_is_combined': False}
Read velocity model#
velocity_file_path = '../data/homo/test_02/TMPL_velocity_model.txt'
velocity_df = pndmod.io.read_velocity(velocity_file_path)
print(velocity_df)
print(velocity_df.attrs)
Depth Vp VpVsRatio Qp Qs Rho Ep Dt Gm
0 40000 3100 1.73 70 50 2400 0.0 0.0 0.0
{'model_type': 'homo', 'model_anisotropy': 'isotropic', 'parameter_descriptions': {'Depth': 'Depth', 'Vp': 'P-wave velocity', 'Vs': 'S-wave velocity', 'VpVsRatio': 'Vp/Vs', 'Qp': 'P-wave quality factor', 'Qs': 'S-wave quality factor', 'Rho': 'density', 'Ep': 'Thomsen epsilon parameter', 'Dt': 'Thomsen delta parameter', 'Gm': 'Thomsen gamma parameter'}, 'parameter_units': {'Depth': 'm', 'Vp': 'm/s', 'Vs': 'm/s', 'VpVsRatio': '', 'Qp': '', 'Qs': '', 'Rho': 'kg/m^3', 'Ep': '', 'Dt': '', 'Gm': ''}}
Set imaging grid parameters#
# Imaging grid parameters
gx = np.arange(-4500, 4500 + 250, 250)
gy = np.arange(-3750, 4750 + 250, 250)
gz = np.arange(1500, 5000 + 250, 250)
# Generate grid points
grid_points = pndmod.utils.generate_grid(x=gx,y=gy,z=gz)
print("Number of grid points:",grid_points.shape[0])
print("grid_points.shape:",grid_points.shape)
Number of grid points: 19425
grid_points.shape: (19425, 3)
Plot geometry and imaging grid#
_ = pndvis.geometry.plot_stations_view(df=geometry_df, grid_points=grid_points, grid_marker_size = 1)
_ = pndvis.geometry.plot_stations_view(df=geometry_df, grid_points=grid_points, grid_marker_size = 1, view = 'xz')
_ = pndvis.geometry.plot_stations_view(df=geometry_df, grid_points=grid_points, grid_marker_size = 1, view = 'yz')
Prepare to compute magnitude sensitivity#
# Specify source parameters
frequency = 10 # Hz
# Minimum S/N for detection on individual channel
min_SNR_p = 2
min_SNR_s = 2
# Minimum stations on which an event must be detected
min_stations_p = 3
min_stations_s = 3
# Use free surface correction
#free_surface = False
free_surface = True
# Save parameters
params = pndmod.classes.DetectionParameters(
f_p=frequency,
f_s=frequency,
min_SNR_p=min_SNR_p,
min_SNR_s=min_SNR_s,
min_stations_p=min_stations_p,
min_stations_s=min_stations_s,
free_surface=free_surface
)
# Define slices to use
slice_X = 0
slice_Y = 0
slice_Z = 2000
# Get slice planes
X_plane_points, X_plane_indices = pndmod.utils.get_slice_coordinates(grid_points=grid_points,slice_dimension=0,slice_coordinate=slice_X)
Y_plane_points, Y_plane_indices = pndmod.utils.get_slice_coordinates(grid_points=grid_points,slice_dimension=1,slice_coordinate=slice_Y)
Z_plane_points, Z_plane_indices = pndmod.utils.get_slice_coordinates(grid_points=grid_points,slice_dimension=2,slice_coordinate=slice_Z)
Compute magnitude sensitivity#
# Compute magnitude sensitivity for P wave
print("Computing magnitude sensitivity for P wave...")
start_time = time()
X_slice_mag_sens_stations_p = pndmod.core.get_mag_sensitivity(grid_coords=X_plane_points,
geometry_df=geometry_df,
velocity_df=velocity_df,
params=params,
wave_mode='P')
Y_slice_mag_sens_stations_p = pndmod.core.get_mag_sensitivity(grid_coords=Y_plane_points,
geometry_df=geometry_df,
velocity_df=velocity_df,
params=params,
wave_mode='P')
Z_slice_mag_sens_stations_p = pndmod.core.get_mag_sensitivity(grid_coords=Z_plane_points,
geometry_df=geometry_df,
velocity_df=velocity_df,
params=params,
wave_mode='P')
end_time = time()
print(f"Computation time: {end_time - start_time} seconds")
# Compute magnitude sensitivity for S wave
print("Computing magnitude sensitivity for S wave...")
start_time = time()
X_slice_mag_sens_stations_s = pndmod.core.get_mag_sensitivity(grid_coords=X_plane_points,
geometry_df=geometry_df,
velocity_df=velocity_df,
params=params,
wave_mode='S')
Y_slice_mag_sens_stations_s = pndmod.core.get_mag_sensitivity(grid_coords=Y_plane_points,
geometry_df=geometry_df,
velocity_df=velocity_df,
params=params,
wave_mode='S')
Z_slice_mag_sens_stations_s = pndmod.core.get_mag_sensitivity(grid_coords=Z_plane_points,
geometry_df=geometry_df,
velocity_df=velocity_df,
params=params,
wave_mode='S')
end_time = time()
print(f"Computation time: {end_time - start_time} seconds")
# Compute magnitude sensitivity for the whole grid for P and S waves
print("Computing magnitude sensitivity for both P and S waves...")
start_time = time()
X_slice_mag_sens_stations_ps = pndmod.core.get_mag_sensitivity(grid_coords=X_plane_points,
geometry_df=geometry_df,
velocity_df=velocity_df,
params=params,
wave_mode='PS')
Y_slice_mag_sens_stations_ps = pndmod.core.get_mag_sensitivity(grid_coords=Y_plane_points,
geometry_df=geometry_df,
velocity_df=velocity_df,
params=params,
wave_mode='PS')
Z_slice_mag_sens_stations_ps = pndmod.core.get_mag_sensitivity(grid_coords=Z_plane_points,
geometry_df=geometry_df,
velocity_df=velocity_df,
params=params,
wave_mode='PS')
end_time = time()
print(f"Computation time: {end_time - start_time} seconds")
Computing magnitude sensitivity for P wave...
Computation time: 0.0036513805389404297 seconds
Computing magnitude sensitivity for S wave...
Computation time: 0.0035088062286376953 seconds
Computing magnitude sensitivity for both P and S waves...
Computation time: 0.0040013790130615234 seconds
Plot magnitude sensitivity#
Plot magnitude sensitivity for P wave#
clb_range = None
plt_levels = None
_ = pndvis.sensitivity.plot_sensitivity_slice(sens_data=X_slice_mag_sens_stations_p, yi=gy, zi=gz,
plot_title="Magnitude sensitivity at X=" + str(slice_X) + " m: YZ view, P-wave",
clb_title="$M_w$",
clb_range=clb_range,
plt_levels=plt_levels)
_ = pndvis.sensitivity.plot_sensitivity_slice(sens_data=Y_slice_mag_sens_stations_p, xi=gx, zi=gz,
plot_title="Magnitude sensitivity at Y=" + str(slice_Y) + " m: XZ view, P-wave",
clb_title="$M_w$",
clb_range=clb_range,
plt_levels=plt_levels)
_ = pndvis.sensitivity.plot_sensitivity_slice(sens_data=Z_slice_mag_sens_stations_p, xi=gx, yi=gy, geometry_df=geometry_df,
plot_title="Magnitude sensitivity at depth " + str(slice_Z) + " m: Map view, P-wave",
clb_title="$M_w$",
clb_range=clb_range,
plt_levels=plt_levels)
Plot magnitude sensitivity for S wave#
_ = pndvis.sensitivity.plot_sensitivity_slice(sens_data=X_slice_mag_sens_stations_s, yi=gy, zi=gz,
plot_title="Magnitude sensitivity at X=" + str(slice_X) + " m: YZ view, S-wave",
clb_title="$M_w$",
clb_range=clb_range,
plt_levels=plt_levels)
_ = pndvis.sensitivity.plot_sensitivity_slice(sens_data=Y_slice_mag_sens_stations_s, xi=gx, zi=gz,
plot_title="Magnitude sensitivity at Y=" + str(slice_Y) + " m: XZ view, S-wave",
clb_title="$M_w$",
clb_range=clb_range,
plt_levels=plt_levels)
_ = pndvis.sensitivity.plot_sensitivity_slice(sens_data=Z_slice_mag_sens_stations_s, xi=gx, yi=gy, geometry_df=geometry_df,
plot_title="Magnitude sensitivity at depth " + str(slice_Z) + " m: Map view, S-wave",
clb_title="$M_w$",
clb_range=clb_range,
plt_levels=plt_levels)
Plot magnitude sensitivity for P and S waves#
_ = pndvis.sensitivity.plot_sensitivity_slice(sens_data=X_slice_mag_sens_stations_ps, yi=gy, zi=gz,
plot_title="Magnitude sensitivity at X=" + str(slice_X) + " m: YZ view, P- and S-waves",
clb_title="$M_w$",
clb_range=clb_range,
plt_levels=plt_levels)
_ = pndvis.sensitivity.plot_sensitivity_slice(sens_data=Y_slice_mag_sens_stations_ps, xi=gx, zi=gz,
plot_title="Magnitude sensitivity at Y=" + str(slice_Y) + " m: XZ view, P- and S-waves",
clb_title="$M_w$",
clb_range=clb_range,
plt_levels=plt_levels)
_ = pndvis.sensitivity.plot_sensitivity_slice(sens_data=Z_slice_mag_sens_stations_ps, xi=gx, yi=gy, geometry_df=geometry_df,
plot_title="Magnitude sensitivity at depth " + str(slice_Z) + " m: Map view, P- and S-waves",
clb_title="$M_w$",
clb_range=clb_range,
plt_levels=plt_levels)
Total running time of the script: (0 minutes 1.883 seconds)