# -*- coding: utf-8 -*-
# vim: tabstop=4 shiftwidth=4 softtabstop=4
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"""
Module :mod:`openquake.hazardlib.scalerel.thingbaijam2017` implements
:class:`ThingbaijamInterface`
:class:`ThingbaijamStrikeSlip`
:class:`ThingbaijamNormalFault`
:class:`ThingbaijamReverseFault`
"""
from numpy import log10
from openquake.hazardlib.scalerel.base import BaseMSRSigma, BaseASRSigma
[docs]class ThingbaijamInterface(BaseMSRSigma, BaseASRSigma):
"""
Thingbaijam, K. K. S., P. M. Mai, and K. Goda (2017). New Empirical
Earthquake Source-Scaling Laws. Bulletin of the Seismological Society of
America, 107(5), pp 2225-2946, doi: 10.1785/0120170017.
Implements moment magnitude-rupture area, rupture area-moment magnitude,
rupture length-magnitude, rupture width-magnitude scaling relations
for subduction interface.
"""
[docs] def get_std_dev_area(self, mag, rake):
"""Returns std for rupture area."""
return 0.150
[docs] def get_std_dev_mag(self, area, rake):
"""Returns std for magnitude."""
return 0.150
[docs] def get_std_dev_length(self, mag):
"""Returns std for rupture length."""
return 0.107
[docs] def get_std_dev_width(self, mag):
"""Returns std for rupture width."""
return 0.099
[docs]class ThingbaijamStrikeSlip(BaseMSRSigma, BaseASRSigma):
"""
Thingbaijam, K. K. S., P. M. Mai, and K. Goda (2017). New Empirical
Earthquake Source-Scaling Laws. Bulletin of the Seismological Society of
America, 107(5), pp 2225-2946, doi: 10.1785/0120170017.
Implements moment magnitude-rupture area, rupture area-moment magnitude,
rupture length-magnitude, rupture width-magnitude scaling relations
for strike-slip faulting.
"""
[docs] def get_std_dev_area(self, mag, rake):
"""Returns std for rupture area."""
return 0.184
[docs] def get_std_dev_mag(self, area, rake):
"""Returns std for magnitude."""
return 0.184
[docs] def get_std_dev_length(self, mag):
"""Returns std for rupture length."""
return 0.151
[docs] def get_std_dev_width(self, mag):
"""Returns std for rupture width."""
return 0.105
[docs]class ThingbaijamNormalFault(BaseMSRSigma, BaseASRSigma):
"""
Thingbaijam, K. K. S., P. M. Mai, and K. Goda (2017). New Empirical
Earthquake Source-Scaling Laws. Bulletin of the Seismological Society of
America, 107(5), pp 2225-2946, doi: 10.1785/0120170017.
Implements moment magnitude-rupture area, rupture area-moment magnitude,
rupture length-magnitude, rupture width-magnitude scaling relations
for normal faulting.
"""
[docs] def get_std_dev_area(self, mag, rake):
"""Returns std for rupture area."""
return 0.181
[docs] def get_std_dev_mag(self, area, rake):
"""Returns std for magnitude."""
return 0.181
[docs] def get_std_dev_length(self, mag):
"""Returns std for rupture length."""
return 0.128
[docs] def get_std_dev_width(self, mag):
"""Returns std for rupture width."""
return 0.128
[docs]class ThingbaijamReverseFault(BaseMSRSigma, BaseASRSigma):
"""
Thingbaijam, K. K. S., P. M. Mai, and K. Goda (2017). New Empirical
Earthquake Source-Scaling Laws. Bulletin of the Seismological Society of
America, 107(5), pp 2225-2946, doi: 10.1785/0120170017.
Implements moment magnitude-rupture area, rupture area-moment magnitude,
rupture length-magnitude, rupture width-magnitude scaling relations
for reverse faulting.
"""
[docs] def get_std_dev_area(self, mag, rake):
"""Returns std for rupture area."""
return 0.121
[docs] def get_std_dev_mag(self, area, rake):
"""Returns std for magnitude."""
return 0.121
[docs] def get_std_dev_length(self, mag):
"""Returns std for rupture length."""
return 0.083
[docs] def get_std_dev_width(self, mag):
"""Returns std for rupture width."""
return 0.087
#: Per-style crustal classes the dispatcher below delegates to.
_STYLE_CLASSES = {
"strike-slip": ThingbaijamStrikeSlip,
"normal": ThingbaijamNormalFault,
"reverse": ThingbaijamReverseFault,
}
#: Average-displacement (slip) coefficients ``log10(AD) = a + b*M`` for
#: crustal events, Thingbaijam et al. (2017) Table 2.
_SLIP = {
"strike-slip": (-4.032, 0.558, 0.227),
"reverse": (-3.156, 0.451, 0.149),
"normal": (-4.967, 0.693, 0.195),
}
[docs]class Thingbaijam2017(BaseMSRSigma, BaseASRSigma):
"""
Thingbaijam, K. K. S., P. M. Mai, and K. Goda (2017). New Empirical
Earthquake Source-Scaling Laws. Bulletin of the Seismological Society of
America, 107(5), pp 2225-2946, doi: 10.1785/0120170017.
Style-dispatching facade over the crustal ``ThingbaijamStrikeSlip`` /
``ThingbaijamNormalFault`` / ``ThingbaijamReverseFault`` relations, with
the additional average-displacement (slip) relation used by the PFD
models. Added for PR-2 of the oq-engine integration plan; it is the
canonical ``Thingbaijam2017`` name expected by the PFD logic tree and
reproduces the width rows ``MSR = 2`` of Mammarella et al. (2024)
Table 1 (see ``openquake/hazardlib/tests/scalerel/pfd_scalerel_test``).
"""
@staticmethod
def _style(rake):
"""Return the faulting-style key for a rake angle in degrees."""
if rake is None:
return "strike-slip"
if (-45 <= rake <= 45) or (rake >= 135) or (rake <= -135):
return "strike-slip"
return "reverse" if rake > 0 else "normal"
def _delegate(self, rake):
return _STYLE_CLASSES[self._style(rake)]()
[docs] def get_std_dev_area(self, mag, rake):
"""Returns std for rupture area."""
return self._delegate(rake).get_std_dev_area(mag, rake)
[docs] def get_std_dev_mag(self, area, rake):
"""Returns std for magnitude."""
return self._delegate(rake).get_std_dev_mag(area, rake)
[docs] def get_std_dev_length(self, mag, rake=None):
"""Returns std for rupture length."""
return self._delegate(rake).get_std_dev_length(mag)
[docs] def get_std_dev_width(self, mag, rake=None):
"""Returns std for rupture width."""
return self._delegate(rake).get_std_dev_width(mag)
[docs] def get_average_displacement(self, mag, style, return_sigma=False):
"""Return median average displacement (m) from moment magnitude."""
a, b, sigma = _SLIP[style]
ad = 10.0 ** (a + b * float(mag))
if return_sigma:
return ad, sigma
return ad
