pyrocko.dataset.crustdb

Access to the USGS Global Crustal Database.

The USGS Global Crustal Database provides empirical velocity measurements of the earth for statistical analysis.

Citation

Mooney, W. D., Laske, G., & Masters, T. G. (1998). CRUST 5.1: A global crustal model at 5x5. Journal of Geophysical Research: Solid Earth, 103(B1), 727-747.

Classes

CrustDB([database_file, parent])	CrustDB is a container for VelocityProfile and provides functions for spatial selection, querying, processing and visualising data from the Global Crustal Database.
VelocityProfile(*args, **kwargs)	Undocumented.

class VelocityProfile(*args, **kwargs)

Bases: Object

Undocumented.

♦ uid

int, optional

Unique ID of measurement

♦ lat

float

Latitude [deg]

♦ lon

float

Longitude [deg]

♦ elevation

float, default: nan

Elevation [m]

♦ vp

numpy.ndarray (pyrocko.guts_array.Array)

P Wave velocities [m/s]

♦ vs

numpy.ndarray (pyrocko.guts_array.Array)

S Wave velocities [m/s]

♦ d

numpy.ndarray (pyrocko.guts_array.Array)

Interface depth, top [m]

♦ h

numpy.ndarray (pyrocko.guts_array.Array)

Interface thickness [m]

♦ heatflow

float, optional

Heatflow [W/m^2]

♦ geographical_location

str, optional

Geographic Location

♦ geological_province

str, optional

Geological Province

♦ geological_age

str, optional

Geological Age

♦ measurement_method

int, optional

Measurement method

♦ publication_reference

str, optional

Publication Reference

interpolateProfile(depths, phase='p', stepped=True)

Get a continuous velocity function at arbitrary depth.

Parameters:

• depth (numpy.ndarray) – Depths to interpolate

• phase (str) – P or S wave velocity, p or s

• stepped (bool) – Use a stepped velocity function or gradient

Returns:

velocities at requested depths

Return type:

numpy.ndarray

plot(axes=None)

Plot the velocity profile, see pyrocko.cake.

Parameters:

axes (matplotlib.axes.Axes) – Axes to plot into.

getLayeredModel()

Get a layered model, see pyrocko.cake.LayeredModel.

iterLayers()

Iterator yielding a pyrocko.cake.Material for each layer.

class CrustDB(database_file=None, parent=None)

Bases: object

CrustDB is a container for VelocityProfile and provides functions for spatial selection, querying, processing and visualising data from the Global Crustal Database.

velocityMatrix(depth_range=(0, 60000.0), ddepth=100.0, phase='p')

Create a regular sampled velocity matrix.

Parameters:

• depth_range (tuple) – Depth range, (dmin, dmax), defaults to (0, 6000.)

• ddepth (float) – Stepping in [m], defaults to 100.

• phase (str) – Phase to calculate p or s, defaults to p

Returns:

Sample depths, veloctiy matrix

Return type:

tuple, (sample_depth, numpy.ndarray)

rmsRank(ref_profile, depth_range=(0, 3500.0), ddepth=100.0, phase='p')

Correlates ref_profile to each profile in the database.

Parameters:

• ref_profile (VelocityProfile) – Reference profile

• depth_range (tuple) – Depth range in [m], (dmin, dmax), defaults to (0, 35000.)

• ddepth (float) – Stepping in [m], defaults to 100.

• phase (str) – Phase to calculate p or s, defaults to p

Returns:

RMS factor length of N_profiles

Return type:

numpy.ndarray

histogram2d(depth_range=(0.0, 60000.0), vel_range=None, ddepth=100.0, dvbin=100.0, ddbin=2000.0, phase='p')

Create a 2D Histogram of all the velocity profiles.

Check numpy.histogram2d() for more information.

Parameters:

• depth_range (tuple) – Depth range in [m], (dmin, dmax), defaults to (0., 60000.)

• vel_range (tuple) – Depth range, (vmin, vmax), defaults to (5500., 8500.)

• ddepth (float) – Stepping in [km], defaults to 100.

• dvbin (float) – Bin size in velocity dimension [m/s], defaults to 100.

• dvbin – Bin size in depth dimension [m], defaults to 2000.

• phase (str) – Phase to calculate p or s, defaults to p

Returns:

numpy.histogram2d()

Return type:

tuple

meanVelocity(depth_range=(0.0, 60000.0), ddepth=100.0, phase='p')

Get mean and standard deviation of velocity profile.

Parameters:

• depth_range (tuple) – Depth range in [m], (dmin, dmax), defaults to (0., 60000.)

• ddepth (float) – Stepping in [m], defaults to 100.

• phase (str) – Phase to calculate p or s, defaults to p

Returns:

depth vector, mean velocities, standard deviations

Return type:

tuple of numpy.ndarray

modeVelocity(depth_range=(0.0, 60000.0), ddepth=100.0, phase='p')

Get mode velocity profile and standard deviation.

Parameters:

• depth_range (tuple) – Depth range in [m], (dmin, dmax), defaults to (0., 60000.)

• ddepth (float) – Stepping in [m], defaults to 100.

• phase (str) – Phase to calculate p or s, defaults to p

Returns:

depth vector, mode velocity, number of counts at each depth

Return type:

tuple of numpy.ndarray

medianVelocity(depth_range=(0.0, 60000.0), ddepth=100.0, phase='p')

Median velocity profile plus std variation.

Parameters:

• depth_range (tuple) – Depth range in [m], (dmin, dmax), defaults to (0., 60000.)

• ddepth (float) – Stepping in [m], defaults to 100.

• phase (str) – Phase to calculate p or s, defaults to p

Returns:

depth vector, median velocities, standard deviations

Return type:

tuple of numpy.ndarray

plotHistogram(vel_range=None, bins=36, phase='vp', axes=None)

Plot 1D histogram of seismic velocities in the container.

Parameters:

• vel_range (tuple) – Velocity range, defaults to (5.5, 8.5)

• bins (int) – bins, defaults to 30 (see numpy.histogram())

• phase (str) – Property to plot out of ['vp', 'vs'], defaults to ‘vp’

• figure (matplotlib.figure.Figure) – Figure to plot in, defaults to None

plot(depth_range=(0, 60000.0), ddepth=100.0, ddbin=2000.0, vel_range=None, dvbin=100.0, percent=False, plot_mode=True, plot_median=True, plot_mean=False, show_cbar=True, aspect=0.02, phase='p', axes=None)

Plot a two 2D Histogram of seismic velocities.

Parameters:

• depth_range (tuple) – Depth range, (dmin, dmax), defaults to (0, 60)

• vel_range (tuple) – Velocity range, (vmin, vmax)

• ddepth (float) – Stepping in [m], defaults to .1

• dvbin (float) – Bin size in velocity dimension [m/s], defaults to .1

• dvbin – Bin size in depth dimension [m], defaults to 2000.

• phase (str) – Phase to calculate p or s, defaults to p

• plot_mode (bool) – Plot the Mode

• plot_mean (bool) – Plot the Mean

• plot_median (bool) – Plot the Median

• axes (matplotlib.axes.Axes) – Axes to plot into, defaults to None

plotVelocitySurface(v_max, d_min=0.0, d_max=6000.0, axes=None)

Plot a triangulated a depth surface exceeding velocity.

exceedVelocity(v_max, d_min=0, d_max=60)

Returns the last depth v_max has not been exceeded.

Parameters:

• v_max – maximal velocity

• dz (float) – depth is sampled in dz steps

• d_max (int) – maximum depth

• d_min (int) – minimum depth

Returns:

Lat, Lon, Depth and uid where v_max is exceeded

Return type:

list of numpy.ndarray

selectRegion(west, east, south, north)

Select profiles within a region by geographic corner coordinates.

Parameters:

• west (float) – west corner

• east (float) – east corner

• south (float) – south corner

• north (float) – north corner

Returns:

Selected profiles

Return type:

CrustDB

selectPolygon(poly)

Select profiles within a polygon.

The algorithm is called the Ray Casting Method

Parameters:

poly – Latitude Longitude pairs of the polygon

Returns:

Selected profiles

Return type:

CrustDB

selectLocation(lat, lon, radius=10)

Select profiles at a geographic location within a radius.

Parameters:

• lat (float) – Latitude in [deg]

• lon (float) – Longitude in [deg]

• radius (float) – Radius in [deg]

Returns:

Selected profiles

Return type:

CrustDB

selectMinLayers(nlayers)

Select profiles with more than nlayers.

Parameters:

nlayers (int) – Minimum number of layers

Returns:

Selected profiles

Return type:

CrustDB

selectMaxLayers(nlayers)

Select profiles with more than nlayers.

Parameters:

nlayers (int) – Maximum number of layers

Returns:

Selected profiles

Return type:

CrustDB

selectMinDepth(depth)

Select profiles describing layers deeper than depth.

Parameters:

depth (float) – Minumum depth in [m]

Returns:

Selected profiles

Return type:

CrustDB

selectMaxDepth(depth)

Select profiles describing layers shallower than depth.

Parameters:

depth (float) – Maximum depth in [m]

Returns:

Selected profiles

Return type:

CrustDB

selectVp()

Select profiles describing P wave velocity.

:returns Selected profiles :rtype: CrustDB

selectVs()

Select profiles describing P wave velocity.

Returns:

Selected profiles

Return type:

CrustDB

exportCSV(filename=None)

Export as CSV file.

Parameters:

filename (str) – Export filename

exportYAML(filename=None)

Export as YAML file.

Parameters:

filename (str) – Export filename