earthscopestraintools.event_processing module

earthscopestraintools.event_processing.calc_hypocentral_dist(eq_latitude, eq_longitude, eq_depth, station_latitude, station_longitude)

Function calculates hypocentral distance (km) between lat,long and earthquake. Note that the distance calculation does not account for Earth’s curvature with depth, and should be used for regional earthquakes only.

Parameters:

  • eq_latitude (float) – latitude of earthquake

  • eq_longitude (float) – longitude of earthquake

  • eq_depth (float) – depth of earthquake

  • station_latitude (float) – latitude of station

  • station_longitude (float) – longitude of station

Returns:

hypocentral distance in km

Return type:

int

earthscopestraintools.event_processing.calculate_magnitude(dynamic_strain_df, hypocentral_distance, site_term, longitude_term)

Calculates a magnitude estimate based on Barbour et al 2021.

Parameters:

  • dynamic_strain_df (pandas.DataFrame) – dataframe containing dynamic strain during an event

  • hypocentral_distance (float) – distance from station to event hypocenter, in km

  • site_term (float) – site term from Barbour et al 2021

  • longitude_term (float) – longitude term from Barbour et al 2021

Returns:

dataframe containing a dynamic strain based magnitude estimate as a function of time

Return type:

pandas.DataFrame

earthscopestraintools.event_processing.calculate_p_s_arrival(eq_latitude, eq_longitude, eq_time, station_latitude, station_longitude)

Function calculates arrival times for P and S waves at a given lat and long

Parameters:

  • eq_latitude (float) – latitude of earthquake

  • eq_longitude (float) – longitude of earthquake

  • eq_time (datetime.datetime) – time of earthquake

  • station_latitude (float) – latitude of station

  • station_longitude (float) – longitude of station

Returns:

p_arrival, s_arrival

Return type:

datetime.datetime

earthscopestraintools.event_processing.dynamic_strain(df, gauge_weights=[1, 1, 1, 1])

Calculates dynamic strain as RMS of gauge strains

Parameters:

  • df (pandas.DataFrame) – dataframe containing gauge strains as columns and time as an index

  • gauge_weights (list, optional) – list of which gauges to include, defaults to [1, 1, 1, 1]

Returns:

dataframe containing a single column of dynamic strain, time as an index

Return type:

pandas.DataFrame

earthscopestraintools.event_processing.get_stations_in_radius(latitude, longitude, depth, radius, print_it=False)

determine list of stations within a given radius from an event, using lat/long in gtsm metadata summary table

Parameters:

  • latitude (float) – event latitude

  • longitude (float) – event longitude

  • depth (float) – event depth

  • radius (float) – radius from event, in km

  • print_it (bool, optional) – option to print list of stations within radius, and calculated distances from event, defaults to False

Returns:

list of four character station codes for stations within the given radius

Return type:

list

earthscopestraintools.event_processing.magnitude_plot(dynamic_strain_df: DataFrame, magnitude_df: DataFrame, eq_time: datetime, eq_mag: datetime, title: str | None = None, save_as: str | None = None)

plot dynamic strain and associated magnitude estimate on the same plot

Parameters:

  • dynamic_strain_df (pd.DataFrame) – dataframe containing dynamic strain during an event

  • magnitude_df (pd.DataFrame) – dataframe containing strain-based magnitude estimate during an event

  • eq_time (datetime.datetime) – event origin time

  • eq_mag (datetime.datetime) – published event magnitude from COMCAT

  • title (str, optional) – plot title, defaults to None

  • save_as (str, optional) – filename to save plot, defaults to None

earthscopestraintools.event_processing.plot_coseismic_offset(df, title: str = '', remove_9s: bool = True, zero: bool = False, detrend: bool | None = None, ymin: float | None = None, ymax: float | None = None, plot_type: str = 'scatter', units: str | None = None, eq_time: datetime | None = None, coseismic_offset: bool = False, color='black', save_as: str | None = None)

plot strain data from an event

Parameters:

  • df (pandas.DataFrame) – strain data including an event signal

  • title (str, optional) – plot title, defaults to “”

  • remove_9s (bool, optional) – option to remove gap fill values, defaults to True

  • zero (bool, optional) – option to zero the data against the first valid index, defaults to False

  • detrend (bool, optional) – option to linearly detrend data, will use pre-event data only if eq_time is provided, defaults to None

  • ymin (float, optional) – y-axis minimum for plot, defaults to None

  • ymax (float, optional) – y-axis maximum for plot, defaults to None

  • plot_type (str, optional) – matplotlib plot type. option of [‘scatter’,’line’], defaults to “scatter”

  • units (str, optional) – units to display on y-axis, defaults to None

  • eq_time (datetime.datetime, optional) – origin time of event, defaults to None

  • coseismic_offset (bool, optional) – option to calculate and display the coseismic offset as a difference of the mean of the first quintile and last quintile of data, defaults to False

  • color (str, optional) – matplotlib color option, defaults to “black”

  • save_as (str, optional) – filename to save plot, defaults to None

earthscopestraintools.event_processing.pre_event_trend_correction(df, eq_time)

calculate a linear trend correction based on any data provided prior to event start time

Parameters:

  • df (pandas.DataFrame) – dataframe containing strain data

  • eq_time (datetime.datetime) – time of event

Returns:

dataframe containing a linear trend correction

Return type:

pandas.DataFrame