Sadigh et. al. 1997

class openquake.hazardlib.gsim.sadigh_1997.SadighEtAl1997[source]

Implements GMPE developed by Sadigh, K., C. -Y. Chang, J. A. Egan, F. Makdisi, and R. R. Youngs (1997) and published as “Attenuation relationships for shallow crustal earthquakes based on California strong motion data”, Seismological Research Letters, 68(1), 180-189.

COEFFS_ROCK_HIMAG = <openquake.hazardlib.gsim.base.CoeffsTable object>

Coefficients tables for rock sites (table 2), for magnitude values above NEAR_FIELD_SATURATION_MAG.

COEFFS_ROCK_LOWMAG = <openquake.hazardlib.gsim.base.CoeffsTable object>

Coefficients tables for rock sites (table 2), for magnitude values of NEAR_FIELD_SATURATION_MAG and below. Damping for spectral acceleration here and in other SA-tables is 5%, see “introduction” section.

COEFFS_ROCK_STDDERR = <openquake.hazardlib.gsim.base.CoeffsTable object>

Coefficient tables for standard error on rock sites (table 3).

COEFFS_SOIL = <openquake.hazardlib.gsim.base.CoeffsTable object>

Coefficient tables for deep soil sites (table 4).

COEFFS_SOIL_IMT_INDEPENDENT = {'c4lowmag': 2.1863, 'c4himag': 0.3825, 'c1ss': -2.17, 'c2': 1.0, 'c3': 1.7, 'c1r': -1.92, 'c5himag': 0.5882, 'c5lowmag': 0.32}

IMT-independent coefficients for deep soil sites (table 4).


Supported intensity measure component is the geometric mean of attr:~openquake.hazardlib.const.IMC.AVERAGE_HORIZONTAL, : see

DEFINED_FOR_INTENSITY_MEASURE_TYPES = set([<class 'openquake.hazardlib.imt.SA'>, <class 'openquake.hazardlib.imt.PGA'>])

Supported intensity measure types are spectral acceleration, and peak ground acceleration, see page 180.


Supported standard deviation type is only total, see table 3.


Supported tectonic region type is active shallow crust, since data consists of California earthquakes mainly.


Magnitude value to separate coefficients table because of near field saturation effect is 6.5. See page 184.

REQUIRES_DISTANCES = set(['rrup'])

Required distance measure is RRup (eq. 1).

REQUIRES_RUPTURE_PARAMETERS = set(['rake', 'mag'])

Required rupture parameters are magnitude and rake (eq. 1).


Required site parameter is only Vs30 (used to distinguish rock and deep soil).

ROCK_VS30 = 750

If site vs30 is more than 750 m/s – treat the soil as rock. See page 180.

get_mean_and_stddevs(sites, rup, dists, imt, stddev_types)[source]

See superclass method for spec of input and result values.