Focal mechanisms

The pygmt.Figure.meca method can plot focal mechanisms, or beachballs. We can specify the focal mechanism nodal planes or moment tensor components as a dict using the spec parameter (or they can be specified as a 1d or 2d array, or within a specified file). The size of plotted beachballs can be specified using the scale parameter.

Out:

<IPython.core.display.Image object>

import pygmt

fig = pygmt.Figure()

# generate a basemap near Washington state showing coastlines, land, and water
fig.coast(
    region=[-125, -122, 47, 49],
    projection="M6c",
    land="grey",
    water="lightblue",
    shorelines=True,
    frame="a",
)

# store focal mechanisms parameters in a dict
focal_mechanism = dict(strike=330, dip=30, rake=90, magnitude=3)

# pass the focal mechanism data to meca in addition to the scale and event
# location
fig.meca(focal_mechanism, scale="1c", longitude=-124.3, latitude=48.1, depth=12.0)

fig.show()