pygmt.Figure.meca

Figure.meca(spec, scale, convention=None, component='full', longitude=None, latitude=None, depth=None, plot_longitude=None, plot_latitude=None, event_name=None, *, region=None, projection=None, offset=None, frame=None, no_clip=None, verbose=None, xshift=None, yshift=None, panel=None, perspective=None, transparency=None, **kwargs)

Plot focal mechanisms.

Full option list at https://docs.generic-mapping-tools.org/latest/supplements/seis/meca.html

Aliases:

• A = offset

• B = frame

• J = projection

• N = no_clip

• R = region

• V = verbose

• X = xshift

• Y = yshift

• c = panel

• p = perspective

• t = transparency

Parameters

• spec (str, 1D array, 2D array, dict, or pd.DataFrame) –

  Data that contains focal mechanism parameters.

  spec can be specified in either of the following types:

  • str: a file name containing focal mechanism parameters as columns. The meanings of each column is:

    • Columns 1 and 2: event longitude and latitude

    • Column 3: event depth (in km)

    • Columns 4 to 3+n: focal mechanism parameters. The number of columns n depends on the choice of convection, which will be described below.

    • Columns 4+n and 5+n: longitude, latitude at which to place beachball. Using 0 0 will plot the beachball at the longitude, latitude given in columns 1 and 2. [optional and requires offset=True to take effect].

    • Text string to appear near the beach ball [optional].

  • 1D array: focal mechanism parameters of a single event. The meanings of columns are the same as above.

  • 2D array: focal mechanim parameters of multiple events. The meanings of columns are the same as above.

  • dict or pd.DataFrame: The dict keys or pd.DataFrame column names determine the focal mechanims convention. For different conventions, the following combination of keys are allowed:

    • "aki": strike, dip, rake, magnitude

    • "gcmt": strike1, dip1, rake1, strike2, dip2, rake2, mantissa, exponent

    • "mt": mrr, mtt, mff, mrt, mrf, mtf, exponent

    • "partial": strike1, dip1, strike2, fault_type, magnitude

    • "principal_axis": t_value, t_azimuth, t_plunge, n_value, n_azimuth, n_plunge, p_value, p_azimuth, p_plunge, exponent

    A dict may contain values for a single focal mechanism or lists of values for multiple focal mechanisms.

    Both dict and pd.DataFrame may optionally contain keys/column names: latitude, longitude, depth, plot_longitude, plot_latitude, and/or event_name.

    For spec in either a str, a 1D array or a 2D array, the convention parameter is required so we know how to interpret the columns. For spec in a dict or a pd.DataFrame, convention is not needed and is ignored if specified.

• scale (str) – Adjusts the scaling of the radius of the beachball, which is proportional to the magnitude. scale defines the size for magnitude = 5 (i.e. scalar seismic moment M0 = 4.0E23 dynes-cm).

• convention (str) –

  Focal mechanism convention. Choose from: - "aki" (Aki & Richards) - "gcmt" (global CMT) - "mt" (seismic moment tensor) - "partial" (partial focal mechanism) - "principal_axis" (principal axis).

  Ignored if spec is a dictionary or pd.DataFrame.

• component (str) –

  The component of the seismic moment tensor to plot.

  • "full": the full seismic moment tensor

  • "dc": the closest double couple defined from the moment tensor (zero trace and zero determinant)

  • "deviatoric": deviatoric part of the moment tensor (zero trace)

• longitude (int, float, list, or 1d numpy array) – Longitude(s) of event location. Must be the same length as the number of events. Will override the longitude values in spec if spec is a dict or pd.DataFrame.

• latitude (int, float, list, or 1d numpy array) – Latitude(s) of event location. Must be the same length as the number of events. Will override the latitude values in spec if spec is a dict or pd.DataFrame.

• depth (int, float, list, or 1d numpy array) – Depth(s) of event location in kilometers. Must be the same length as the number of events. Will override the depth values in spec if spec is a dict or pd.DataFrame.

• plot_longitude (int, float, list, or 1d numpy array) – Longitude(s) at which to place beachball. Must be the same length as the number of events. Will override the plot_longitude values in spec if spec is a dict or pd.DataFrame.

• plot_latitude (int, float, list, or 1d numpy array) – Latitude(s) at which to place beachball. List must be the same length as the number of events. Will override the plot_latitude values in spec if spec is a dict or pd.DataFrame.

• event_name (str or list of str, or 1d numpy array) – Text strings (e.g., event names) to appear near the beach ball. List must be the same length as the number of events. Will override the event_name values in spec if spec is a dict or pd.DataFrame.

• offset (bool or str) – [+ppen][+ssize]. Offsets beachballs to the longitude, latitude specified in the last two columns of the input file or array, or by ``plot_longitude`` and ``plot_latitude`` if provided. A small circle is plotted at the initial location and a line connects the beachball to the circle. Use **+s*size to set the diameter of the circle [Default is no circle]. Use +ppen to set the line pen attributes [Default is 0.25p].

• no_clip (bool) – Does NOT skip symbols that fall outside frame boundary specified by region [Default is False, i.e. plot symbols inside map frame only].

• projection (str) – projcode[projparams/]width. Select map projection.

• region (str or list) – xmin/xmax/ymin/ymax[+r][+uunit]. Specify the region of interest.

• frame (bool or str or list) – Set map boundary frame and axes attributes.

• verbose (bool or str) –

  Select verbosity level [Default is w], which modulates the messages written to stderr. Choose among 7 levels of verbosity:

  • q - Quiet, not even fatal error messages are produced

  • e - Error messages only

  • w - Warnings [Default]

  • t - Timings (report runtimes for time-intensive algorithms);

  • i - Informational messages (same as verbose=True)

  • c - Compatibility warnings

  • d - Debugging messages

• xshift (str) – [a|c|f|r][xshift]. Shift plot origin in x-direction.

• yshift (str) – [a|c|f|r][yshift]. Shift plot origin in y-direction. Full documentation is at https://docs.generic-mapping-tools.org/latest/gmt.html#xy-full.

• panel (bool or int or list) – [row,col|index]. Select a specific subplot panel. Only allowed when in subplot mode. Use panel=True to advance to the next panel in the selected order. Instead of row,col you may also give a scalar value index which depends on the order you set via autolabel when the subplot was defined. Note: row, col, and index all start at 0.

• perspective (list or str) – [x|y|z]azim[/elev[/zlevel]][+wlon0/lat0[/z0]][+vx0/y0]. Select perspective view and set the azimuth and elevation angle of the viewpoint. Default is [180, 90]. Full documentation is at https://docs.generic-mapping-tools.org/latest/gmt.html#perspective-full.

• transparency (int or float) – Set transparency level, in [0-100] percent range. Default is 0, i.e., opaque. Only visible when PDF or raster format output is selected. Only the PNG format selection adds a transparency layer in the image (for further processing).

Examples using pygmt.Figure.meca

Focal mechanisms

Focal mechanisms