FE tool - python fault source computation

[Ben Wyss]

Once the fault info is parsed (bug 863286), using Python, some fields transformations will need to take place, more details to come...

[John Tarter (toh2)]

12.10.11 Equations for calculated fault source attributes
An excel spreadsheet example has also been sent by email.

Length (units = km)
Preferred (Lpref) = automatically measured
Minimum (Lmin) = Lpref – (Lpref x 0.1)
Maximum (Lmax) = Lpref + (Lpref x 0.1)

Width (units = km)
Preferred (Wpref) = (LSDpref – USDpref) / Sin(Dippref)
Minimum (Wmin) = (LSDmin – USDmax) / Sin(Dipmax)
Maximum (Wmax) = (LSDmax – USDmin) / Sin(Dipmin)

LSD = Lower Seismogenic Depth (km)
USD = Upper Seismogenic Depth (km)
Dip = Dip (radians) = Dip (degrees) x Pi / 180
Sin = sine angle

Area (units = km2)
Preferred (Apref) = Lpref x Wpref
Minimum (Amin) = Lmin x Wmin
Maximum (Amax) = Lmax x Lmin

Maximum Magnitude (Data Dictionary Appendix A)
Preferred (Mwpref) = from chosen magnitude scaling relationship1 using Lpref, Wpref, and/or Apref
Minimum (Mwmin) = from chosen magnitude scaling relationship1 using Lmin, Wmin, and/or Amin
Maximum (Mwmax) = from chosen magnitude scaling relationship1 using Lmax, Wmax, and/or Amax

1 Complete list of magnitude scaling relationships (laws) not complete, but include the following three in v1.0:

New Zealand – oblique slip
Mwpref = 4.18 + 2/3logWpref + 4/3logLpref
Mwmin = 4.18 + 2/3logWmin+ 4/3logLmin
Mwmax = 4.18 + 2/3logWmax + 4/3logLmax

Hanks and Bakun (2008) – A ≤ 537 km2
Mwpref = 3.98 + logApref
Mwmin = 3.98 + logAmin
Mwmax = 3.98 + logAmax

Hanks and Bakun (2008) – A > 537 km2
Mwpref = 3.07 + 4/3logApref
Mwmin = 3.07 + 4/3logAmin
Mwmax = 3.07 + 4/3logAmax

Recurrence Interval (units = years) (Data Dictionary Appendix B)
Preferred (RIpref) = Dpref x 1000 / SRpref
Minimum (RImin) = Dmin x 1000 / SRmax
Maximum (RImax) = Dmax x 1000 / SRmin

D = displacement (m)
SR = net slip rate (mm/yr)

Dpref = (Mopref / (300000000000 x Apref x 10000000000)) x 0.01
Dmin= (Momin / (300000000000 x Amin x 10000000000)) x 0.01
Dmax= (Momax / (300000000000 x Amax x 10000000000)) x 0.01

Mopref = 10^(16.05+(1.5 x Mwpref))
Momin = 10^(16.05+(1.5 x Mwmin))
Momax = 10^(16.05+(1.5 x Mwmax))

Data completeness factor (number between 1 and 4)
= (USDdcf + LSDdcf + Dipdcf + DipDirdcf + SlipTypedcf + (5 x SRdcf) + AsSlipdcf) / 11

USDdcf = upper seismogenic depth data completeness factor
LSDdcf = lower seismogenic depth data completeness factor
Dipdcf = dip data completeness factor
DipDirdcf = dip direction data completeness factor
SlipTypedcf = slip type data completeness factor
SRdcf = net slip rate data completeness factor
AsSlipdcf = aseismic-slip data completeness factor

[Anton Gritsay (angri)]

Pull request: https://bugs.launchpad.net/openquake/+bug/863288