Youngs et al. 1997

class openquake.hazardlib.gsim.youngs_1997.YoungsEtAl1997SInter

Implements GMPE developed by R.R Youngs, S-J, Chiou, W.J. Silva, J.R. Humphrey and published as “Strong Ground Motion Attenuation Relationships for Subduction Zone Earthquakes” (Seismological Research Letters Volume 68, No. 1, pages 58-73, 1997). This class implements the equations for ‘Subduction Interface’ (that’s why the class name ends with ‘SInter’). Mean value for SA at 4 s on rock (not originally supported) is obtained from mean value at 3 s divided by a factor equal to 0.399 (scaling factor computed in the context of the SHARE project obtained as average ratio between median values at 4 and 3 seconds as predicted by SHARE subduction GMPEs).

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

Coefficient table containing rock coefficients, taken from table 2, p. 67

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

Coefficient table containing soil coefficients, taken from table 2, p. 67

CONSTS = {'A2_rock': 1.414, 'A7_rock': 0.3846, 'A3_soil': 10, 'A6_soil': 0.00648, 'A7_soil': 0.3643, 'A4_rock': 1.7818, 'A5_rock': 0.554, 'A4_soil': 1.097, 'A5_soil': 0.617, 'A2_soil': 1.438, 'A1_soil': -0.6687, 'A1_rock': 0.2418, 'A3_rock': 10, 'A6_rock': 0.00607}

constants for mean value calculation, see table 2, page 67.

DEFINED_FOR_INTENSITY_MEASURE_COMPONENT = 'Average horizontal'

Supported intensity measure component is the average horizontal component

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

Supported intensity measure types are spectral acceleration, and peak ground acceleration, see table 2, page 67.

DEFINED_FOR_STANDARD_DEVIATION_TYPES = set(['Total'])

Supported standard deviation types is total, table 2, page 67.

DEFINED_FOR_TECTONIC_REGION_TYPE = 'Subduction Interface'

Supported tectonic region type is subduction interface

REQUIRES_DISTANCES = set(['rrup'])

Required distance measure is Rrup, see equations 1 and 2, page 59 and 66, respectively.

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

Required rupture parameters are magnitude and focal depth, see equations 1 and 2, pages 59 and 66, respectively.

REQUIRES_SITES_PARAMETERS = set(['vs30'])

Required site parameters is Vs30, used to distinguish between rock and soil sites, see paragraph ‘Strong Motion Data Base’, page 59.

ROCK_VS30 = 760

Vs30 value representing typical rock conditions in California.

get_mean_and_stddevs(sites, rup, dists, imt, stddev_types)

See superclass method for spec of input and result values.

class openquake.hazardlib.gsim.youngs_1997.YoungsEtAl1997SSlab

Implements GMPE developed by R.R Youngs, S-J, Chiou, W.J. Silva, J.R. Humphrey and published as “Strong Ground Motion Attenuation Relationships for Subduction Zone Earthquakes” (Seismological Research Letters Volume 68, No. 1, pages 58-73, 1997). This class implements the equations for ‘Subduction IntraSlab’ (that’s why the class name ends with ‘SSlab’). Mean value for SA at 4 s on rock (not originally supported) is obtained from mean value at 3 s divided by a factor equal to 0.399 (scaling factor computed in the context of the SHARE project obtained as average ratio between median values at 4 and 3 seconds as predicted by SHARE subduction GMPEs).

DEFINED_FOR_TECTONIC_REGION_TYPE = 'Subduction IntraSlab'

Supported tectonic region type is subduction intraslab

get_mean_and_stddevs(sites, rup, dists, imt, stddev_types)

See superclass method for spec of input and result values.

class openquake.hazardlib.gsim.youngs_1997.YoungsEtAl1997GSCSSlabBest

Implement modification to YoungsEtAl1997SSlab as defined by GSC (Geological Survey of Canada) for the 2010 Western Canada Model. Includes adjustement for firm ground. The model is associated to the ‘Best’ case, that is mean value unaffected.

get_mean_and_stddevs(sites, rup, dists, imt, stddev_types)

See superclass method for spec of input and result values.

class openquake.hazardlib.gsim.youngs_1997.YoungsEtAl1997GSCSSlabUpperLimit

Implement modification to YoungsEtAl1997SSlab as defined by GSC (Geological Survey of Canada) for the 2010 Western Canada Model. Includes adjustement for firm ground. The model is associated to the ‘Upper Limit’ case, that is mean value plus 0.7 natural logarithm.

get_mean_and_stddevs(sites, rup, dists, imt, stddev_types)

See superclass method for spec of input and result values.

class openquake.hazardlib.gsim.youngs_1997.YoungsEtAl1997GSCSSlabLowerLimit

Implement modification to YoungsEtAl1997SSlab as defined by GSC (Geological Survey of Canada) for the 2010 Western Canada Model. Includes adjustement for firm ground. The model is associated to the ‘Lower Limit’ case, that is mean value minus 0.7 natural logarithm.

get_mean_and_stddevs(sites, rup, dists, imt, stddev_types)

See superclass method for spec of input and result values.

class openquake.hazardlib.gsim.youngs_1997.YoungsEtAl1997SInterNSHMP2008

Extends YoungsEtAl1997SInter and fix rupture hypocenter depth at 20 km as defined by the National Seismic Hazard Mapping Project (NSHMP) for the 2008 US model.

The class implement the equation as coded in subroutine getGeom in hazSUBXnga.f Fortran code available at: http://earthquake.usgs.gov/hazards/products/conterminous/2008/software/

get_mean_and_stddevs(sites, rup, dists, imt, stddev_types)

See superclass method for spec of input and result values.

Call superclass method by passing new rupture context object with hypocentral depth set to 20 km