Stress projection API#

Direct calls use Pa, NED tensor order [NN,NE,ND,EE,ED,DD] and degrees. These functions operate on supplied stress and do not need a Green’s-function library. See scientific conventions.

dyncfs.cfs_static.cal_coulomb_failure_stress(norm_stress, shear_stress, mu_f=0.4)#: norm_stress is tension-positive normal stress in Pa; shear_stress is signed shear in Pa; mu_f is dimensionless effective friction. Return shear_stress + mu_f * norm_stress, preserving NumPy broadcasting.

dyncfs.cfs_static.cal_coulomb_failure_stress_poroelasticity(norm_stress, shear_stress, mean_stress, mu_f=0.6, B_pore=0)#: Normal, shear and mean stresses are in Pa; mean_stress is tensor trace/3. Dimensionless mu_f and B_pore give shear + mu_f*(normal-B_pore*mean). Returns a scalar or broadcast array. Note its friction default is 0.6; the single-point wrappers default to 0.4.

dyncfs.cfs_static.cal_cfs_static_single_point_fix_fm(obs_fm, stress, mu_f=0.4, B_pore=0.0)#: obs_fm is [strike,dip,rake]; stress is a six-entry perturbation tensor. Return (n,d,sigma,tau,cfs): two (3,) NED unit vectors and three scalar stresses in Pa. mu_f and B_pore select the Coulomb formula.

dyncfs.cfs_static.cal_cfs_static_single_point_opt_rake(obs_strike, obs_dip, stress, tectonic_stress, mu_f=0.4, B_pore=0.0)#: obs_strike/obs_dip fix the plane. stress and tectonic_stress are six-entry NED tensors in Pa. Optimize rake using total traction, then resolve perturbation stress. Return (n,d,sigma,tau,cfs,rake), with vectors (3,), stresses in Pa and rake in degrees.

dyncfs.cfs_static.cal_cfs_static_single_point_opt_plane(stress, tectonic_stress_type, tectonic_stress, mu_f=0.4, B_pore=0.0)#: stress is the perturbation tensor in Pa. Type 1 uses a full tectonic_stress tensor in Pa; type 2 uses ordered principal-axis azimuth/plunge pairs in degrees. Invalid types raise ValueError. Return ([n1,d1,sigma1,tau1], [n2,d2,sigma2,tau2], cfs). The one CFS value is evaluated on plane 2. Units follow the other projection functions.

dyncfs.cfs_dynamic.cal_stress_vector_ned_dynamic(stress_ned, n)#: stress_ned has shape (T,6) in Pa and n is a three-component fixed NED normal. Return traction vectors (T,3) in Pa. This helper does no synthesis or disk I/O.

dyncfs.signal_process.correct_zero_frequency(data, srate, A0, f_c, tc1, tc2, ratio_interp=0)#: data is a 1D series, normally stress rate in Pa/s; srate is Hz; A0 is the desired integral (Pa for stress rate). f_c counts frequency bins, not Hz. tc1/tc2 are start/inclusive and stop/exclusive sample indices clipped to the data. Positive ratio_interp resamples before FFT; 0 disables it. Return a same-length corrected array without mutating input. Outside the corrected window the returned series is zero; a window shorter than two samples instead returns an unchanged copy.

dyncfs.utils.static_stress_ned2enz(stress_ned)#: Convert a stress array (6,) or (N,6) from NED to ENU component order, exchanging horizontal axes and reversing vertical-shear signs. Return a new same-shaped array with unchanged units.