Source code for openquake.hazardlib.gsim.atkinson_boore_1995

# -*- coding: utf-8 -*-
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"""
Module exports :class:`AtkinsonBoore1995GSCBest`,
:class:`AtkinsonBoore1995GSCLowerLimit`,
:class:`AtkinsonBoore1995GSCUpperLimit`
"""
import numpy as np

from openquake.hazardlib.gsim.base import GMPE, CoeffsTable
from openquake.hazardlib import const
from openquake.hazardlib.imt import PGA, SA


[docs]class AtkinsonBoore1995GSCBest(GMPE): """ Implement equation used by the Geological Survey of Canada (GSC) for the 2010 Eastern Canada National Seismic Hazard Model. The equation fits the table values defined by Gail M. Atkinson and David M. Boore in "Ground-Motion Relations for Eastern North America", Bullettin of the Seismological Society of America, Vol. 85, No. 1, pp. 17-30, February 1995. Table of coefficients were provided by GSC and are associated to the 'Best' case (that is mean value unaffected). The class assumes magnitude to be in Mblg scale. The Atkinson 1993 conversion equation is used to obtain Mw values. """ #: Supported tectonic region type is stable continental, given #: that the equations have been derived for Eastern North America DEFINED_FOR_TECTONIC_REGION_TYPE = const.TRT.STABLE_CONTINENTAL #: Supported intensity measure types are spectral acceleration, #: and peak ground acceleration DEFINED_FOR_INTENSITY_MEASURE_TYPES = {PGA, SA} #: Supported intensity measure component is random horizontal #: :attr:`~openquake.hazardlib.const.IMC.RANDOM_HORIZONTAL`, #: see page 22 in Atkinson and Boore's manuscript DEFINED_FOR_INTENSITY_MEASURE_COMPONENT = const.IMC.RANDOM_HORIZONTAL #: Supported standard deviation type is total DEFINED_FOR_STANDARD_DEVIATION_TYPES = {const.StdDev.TOTAL} #: site params are not required REQUIRES_SITES_PARAMETERS = set() #: Required rupture parameter is magnitude REQUIRES_RUPTURE_PARAMETERS = {'mag'} #: Required distance measure is hypocentral distance #: see page 18 in Atkinson and Boore's manuscript REQUIRES_DISTANCES = {'rhypo'}
[docs] def compute(self, ctx, imts, mean, sig, tau, phi): """ See :meth:`superclass method <.base.GroundShakingIntensityModel.compute>` for spec of input and result values. """ for m, imt in enumerate(imts): C = self.COEFFS[imt] # clip rhypo at 10 (this is the minimum distance used in # deriving the equation), see page 22, this avoids singularity # in mean value equation rhypo = ctx.rhypo.copy() rhypo[rhypo < 10] = 10 # convert magnitude from Mblg to Mw mag = ctx.mag * 0.98 - 0.39 if ctx.mag <= 5.5 else \ 2.715 - 0.277 * ctx.mag + 0.127 * ctx.mag * ctx.mag # functional form as explained in 'Youngs_fit_to_AB95lookup.doc' f1 = np.minimum(np.log(rhypo), np.log(70.)) f2 = np.maximum(np.log(rhypo / 130.), 0) mean[m] = ( C['c1'] + C['c2'] * mag + C['c3'] * mag ** 2 + (C['c4'] + C['c5'] * mag) * f1 + (C['c6'] + C['c7'] * mag) * f2 + C['c8'] * rhypo) sig[m] = .69
#: coefficient table provided by GSC COEFFS = CoeffsTable(sa_damping=5, table="""\ IMT c1 c2 c3 c4 c5 c6 c7 c8 pga -1.329 1.272 -0.08240 -2.556 0.17220 -1.9600 0.17460 -0.0045350 0.1 -2.907 1.522 -0.08528 -2.052 0.12484 -1.4224 0.07965 -0.0043090 0.2 -5.487 1.932 -0.10290 -1.818 0.09797 -1.0760 0.06075 -0.0033250 0.3 -7.567 2.284 -0.11930 -1.734 0.08814 -0.9551 0.04392 -0.0025700 0.5 -9.476 2.503 -0.12310 -1.631 0.07610 -1.0490 0.06224 -0.0019590 1.0 -11.134 2.470 -0.10569 -1.520 0.06165 -0.9106 0.05248 -0.001497 2.0 -13.210 2.945 -0.15670 -1.864 0.11620 -0.7653 0.02729 -0.0009921 """)
[docs]class AtkinsonBoore1995GSCLowerLimit(AtkinsonBoore1995GSCBest): """ Implement equation used by the Geological Survey of Canada (GSC) for the 2010 Eastern Canada National Seismic Hazard Model. The equation fits the table values defined by Gail M. Atkinson and David M. Boore in "Ground-Motion Relations for Eastern North America", Bullettin of the Seismological Society of America, Vol. 85, No. 1, pp. 17-30, February 1995. Table of coefficients were provided by GSC and are associated to the 'Lower Limit' case (that is mean value decreased). """ #: coefficient table provided by GSC COEFFS = CoeffsTable(sa_damping=5, table="""\ IMT c1 c2 c3 c4 c5 c6 c7 c8 pga -2.204 1.272 -0.08240 -2.556 0.17220 -1.9600 0.17460 -0.0045350 0.1 -3.782 1.522 -0.08528 -2.052 0.12484 -1.4224 0.07965 -0.0043090 0.2 -6.224 1.932 -0.10290 -1.818 0.09797 -1.0760 0.06075 -0.0033250 0.3 -8.212 2.284 -0.11930 -1.734 0.08814 -0.9551 0.04392 -0.0025700 0.5 -10.029 2.503 -0.12310 -1.631 0.07610 -1.0490 0.06224 -0.0019590 1.0 -11.548 2.470 -0.10569 -1.520 0.06165 -0.9106 0.05248 -0.001497 """)
[docs]class AtkinsonBoore1995GSCUpperLimit(AtkinsonBoore1995GSCBest): """ Implement equation used by the Geological Survey of Canada (GSC) for the 2010 Eastern Canada National Seismic Hazard Model. The equation fits the table values defined by Gail M. Atkinson and David M. Boore in "Ground-Motion Relations for Eastern North America", Bullettin of the Seismological Society of America, Vol. 85, No. 1, pp. 17-30, February 1995. Table of coefficients were provided by GSC and are associated to the 'Upper Limit' case (that is mean value increased). """ #: coefficient table provided by GSC COEFFS = CoeffsTable(sa_damping=5, table="""\ IMT c1 c2 c3 c4 c5 c6 c7 c8 pga -1.030 1.272 -0.08240 -2.556 0.17220 -1.9600 0.17460 -0.0045350 0.1 -2.608 1.522 -0.08528 -2.052 0.12484 -1.4224 0.07965 -0.0043090 0.2 -4.911 1.932 -0.10290 -1.818 0.09797 -1.0760 0.06075 -0.0033250 0.3 -6.784 2.284 -0.11930 -1.734 0.08814 -0.9551 0.04392 -0.0025700 0.5 -8.509 2.503 -0.12310 -1.631 0.07610 -1.0490 0.06224 -0.0019590 1.0 -9.891 2.470 -0.10569 -1.520 0.06165 -0.9106 0.05248 -0.001497 """)