Geophysics operators
61 operators in the geophysics category of the live registry. Each is a named formula you can compose inside a state contract or call directly through POST /api/zeq/compute. KO42 is always on; add up to three more per call (total ≤ 4), per the 7-step protocol.
| Operator | Description | Equation |
|---|---|---|
GP1 | Gravitational acceleration at distance r from a point mass, derived from Newton's universal law of gravitation. | g = \frac{GM}{r^2} |
GP10 | Moment magnitude with 1.287 Hz kinematic modulation for Zeq-enhanced seismic magnitude estimation. | M_w = \frac{2}{3}(\log_{10}M_0 - 9.1) \cdot [1 + \alpha \sin(2\pi \cdot 1.287t)] |
GP11 | Fourier's law of heat conduction stating that heat flux is proportional to the negative temperature gradient scaled by thermal conductivity. | q = -k\nabla T |
GP12 | Geothermal gradient expressing the rate of temperature increase with depth as the ratio of heat flux to thermal conductivity. | \frac{\partial T}{\partial z} = \frac{q}{k} |
GP13 | Thermal density variation approximation relating density change to temperature departure from a reference state through the thermal expansion coefficient. | \rho = \rho_0(1 + \alpha\Delta T) |
GP14 | Hydrostatic pressure equation giving the pressure at depth in a fluid column from density, gravitational acceleration, and height. | P = \rho g h |
GP15 | Poisson's equation for gravitational potential relating its Laplacian to the local mass density scaled by the gravitational constant. | \nabla^2 U = -4\pi G\rho |
GP16 | Geoid height computed as the ratio of the disturbing potential to normal gravity, measuring the geoid-ellipsoid separation. | N = \frac{U}{g} |
GP17 | North-south component of the deflection of the vertical, measuring the angular difference between the geoid normal and the ellipsoid normal. | \xi = \frac{1}{R}\frac{\partial N}{\partial\phi} |
GP18 | East-west component of the deflection of the vertical, measuring the angular deviation of the plumb line from the geodetic normal. | \eta = \frac{1}{R\cos\phi}\frac{\partial N}{\partial\lambda} |
GP19 | Rayleigh number indicating the onset of thermal convection as the ratio of buoyancy-driven to diffusion-restrained transport in a fluid layer. | Ra = \frac{g\alpha\Delta T d^3}{\nu\kappa} |
GP2 | Gravity anomaly defined as the difference between observed and reference gravitational acceleration, revealing subsurface density variations. | \Delta g = g_{obs} - g_{ref} |
GP20 | Peclet number comparing advective to diffusive heat transport, governing whether convection or conduction dominates thermal transfer. | Pe = \frac{vL}{\kappa} |
GP3 | Period of a physical (compound) pendulum determined by the moment of inertia, mass, and distance from pivot to center of gravity. | T = 2\pi\sqrt{\frac{I}{mgh}} |
GP4 | Magnetic field relation in matter combining the applied field and magnetization through the permeability of free space. | B = \mu_0(H + M) |
GP5 | Zeq-modified Ampere's law incorporating a 1.287 Hz sinusoidal modulation into the current density for geomagnetic field modeling. | \nabla \times \vec{B} = \mu_0 \vec{J} \cdot [1 + \alpha \sin(2\pi \cdot 1.287t)] |
GP6 | Gauss's law for electric displacement relating the divergence of the D-field to the free charge density in a dielectric medium. | \nabla \cdot \vec{D} = \rho_f |
GP7 | P-wave velocity with 1.287 Hz kinematic modulation for Zeq geophysical wave propagation analysis. | v_P = \sqrt{\frac{K + 4\mu/3}{\rho}} \cdot [1 + \alpha \sin(2\pi \cdot 1.287t)] |
GP8 | S-wave velocity with 1.287 Hz kinematic modulation for Zeq geophysical shear wave propagation analysis. | v_S = \sqrt{\frac{\mu}{\rho}} \cdot [1 + \alpha \sin(2\pi \cdot 1.287t)] |
GP9 | Local magnitude scale computing earthquake size from the logarithm of maximum seismogram amplitude with distance corrections. | M_L = \log_{10}A - \log_{10}A_0 |
GPO1 | Plate tectonic velocity describing the rate and direction of lithospheric plate motion relative to a fixed reference frame. | \vec{v}{plate} = \vec{\omega} \times \vec{r} + \vec{v}{mantle} + \vec{v}{slab_pull} + \vec{v}{ridge_push} |
GPO10 | Subduction zone thermal structure modeling the temperature field of a descending slab from plate age, velocity, and dip angle. | v_{slab} = \sqrt{\frac{\Delta \rho g \sin\theta}{\rho \eta}} L \cdot \eta_{rheology} \cdot f_{age} |
GPO11 | Continental rift valley extension rate relating crustal thinning to far-field tectonic stress and lithospheric rheology. | \frac{\partial u}{\partial t} = \frac{\partial}{\partial x}\left(D\frac{\partial u}{\partial x}\right) + \dot{\epsilon}_0 + \alpha \Delta T + \beta \nabla^2 u |
GPO12 | Hotspot track model predicting the age-distance progression of volcanic islands from plate motion over a stationary mantle plume. | \frac{d\vec{x}{volcano}}{dt} = \vec{v}{plate} - \vec{v}{plume} + \vec{v}{mantle_wind} + \vec{\eta}_{deflection} |
GPO2 | Mantle convection equation coupling thermal buoyancy with viscous flow to model large-scale circulation in the Earth's mantle. | \frac{D\vec{v}}{Dt} = -\frac{1}{\rho}\nabla p + \nu\nabla^2\vec{v} + \alpha g \Delta T \hat{r} + \vec{F}_{compositional} |
GPO3 | Terrestrial heat flow measured as the product of thermal conductivity and the vertical temperature gradient through the lithosphere. | q = -k\nabla T + \rho c_p \vec{v} T + q_{radioactive} + q_{adiabatic} |
GPO4 | Isostatic equilibrium principle balancing crustal loads against buoyant support from the underlying mantle to determine topographic compensation. | \rho_c h_c = \rho_m h_m, \quad \Delta h = \frac{\rho_m - \rho_l}{\rho_m} h_l |
GPO5 | Fault mechanics relating shear stress, normal stress, and friction coefficient to predict slip initiation on geological faults. | \tau = \tau_0 + \mu(\sigma_n - p) + A \ln\left(\frac{V}{V_0}\right) + B \ln\left(\frac{V_0 \theta}{D_c}\right) |
GPO6 | Earthquake scaling law relating rupture dimensions, stress drop, and seismic moment for estimating expected ground motion. | M_0 = \mu A D, \quad M_w = \frac{2}{3}\log_{10} M_0 - 6.07 |
GPO7 | Seismic wave propagation equation describing how elastic waves travel through heterogeneous Earth materials with velocity and attenuation. | \rho \frac{\partial^2 u_i}{\partial t^2} = \frac{\partial \sigma_{ij}}{\partial x_j} + f_i, \quad \sigma_{ij} = C_{ijkl} \epsilon_{kl} |
GPO8 | Volcanic eruption dynamics modeling magma ascent rate from chamber overpressure, conduit geometry, and magma viscosity. | Q = \frac{\pi \Delta P r^4}{8\mu L} \cdot f(\phi) \cdot g(Re), \quad \Delta P = \rho g \Delta h - \Delta P_{viscous} |
GPO9 | Magma chamber pressure evolution from the balance of magma influx, volatile exsolution, and elastic wall rock deformation. | \frac{dV}{dt} = Q_{in} - Q_{out} - \frac{dV_{crystallization}}{dt} + \beta V \Delta T |
MET1 | Hydrostatic equation relating the vertical pressure gradient to the product of air density and gravitational acceleration in the atmosphere. | \frac{dp}{dz} = -\rho g |
MET10 | Potential vorticity combining absolute vorticity and static stability into a conserved quantity for adiabatic, frictionless flow. | \zeta = \frac{\partial v}{\partial x} - \frac{\partial u}{\partial y} |
MET11 | Omega equation diagnosing vertical velocity in pressure coordinates from differential vorticity advection and thermal advection. | \frac{d\zeta}{dt} = -(\zeta + f)\nabla \cdot \vec{v} |
MET12 | Convective Available Potential Energy integrating buoyancy of a lifted parcel over depth to assess thunderstorm potential. | PV = \frac{\zeta + f}{\rho}\frac{\partial\theta}{\partial z} |
MET13 | Atmospheric kinetic energy per unit mass computed from wind speed squared, used in storm intensity and energy budget analyses. | \omega = \frac{dp}{dt} |
MET14 | Atmospheric moisture flux convergence driving precipitation, computed from the divergence of the vertically integrated water vapor transport. | CAPE = \int_{LFC}^{EL} g\frac{T_p - T_e}{T_e} dz |
MET15 | Atmospheric radiation balance determining net radiative heating from the difference between absorbed shortwave and emitted longwave radiation. | K = \frac{1}{2}(u^2 + v^2) |
MET2 | Barometric formula predicting exponential pressure decrease with altitude in an isothermal atmosphere using the scale height. | P = P_0 e^{-z/H} |
MET3 | Environmental lapse rate giving the rate of temperature decrease with altitude in the troposphere under standard conditions. | \Gamma = -\frac{dT}{dz} = 9.8 \text{ K/km} |
MET4 | Potential temperature converting measured temperature to the value it would have if adiabatically brought to a reference pressure level. | \Gamma_s = \Gamma\frac{1 + L_v r_s / R_d T}{1 + L_v^2 r_s / c_p R_v T^2} |
MET5 | Clausius-Clapeyron equation describing the exponential increase of saturation vapor pressure with temperature for phase equilibria. | \theta = T\left(\frac{P_0}{P}\right)^{R/c_p} |
MET6 | Relative humidity expressed as the ratio of actual water vapor pressure to the saturation vapor pressure at the same temperature. | e_s = 6.11 \exp\left(\frac{17.27 T}{T + 237.3}\right) |
MET7 | Geostrophic wind speed resulting from the balance between the pressure gradient force and the Coriolis force in large-scale flow. | RH = \frac{e}{e_s} \times 100\% |
MET8 | Ageostrophic wind component representing the departure from geostrophic balance that drives vertical motion and frontogenesis. | \vec{v}_g = -\frac{1}{\rho f}\hat{k} \times \nabla P |
MET9 | Relative vorticity measuring the local spin of air parcels about a vertical axis from the horizontal wind field derivatives. | \vec{v}_a = \vec{v} - \vec{v}_g |
OC10 | Richardson number comparing buoyancy-driven stability to velocity shear, predicting the onset of turbulent mixing in stratified flows. | Ri = \frac{N^2}{(\partial u/\partial z)^2} |
OC11 | Brunt-Vaisala frequency measuring the natural oscillation frequency of a vertically displaced fluid parcel in a stably stratified ocean. | N = \sqrt{-\frac{g}{\rho}\frac{\partial\rho}{\partial z}} |
OC12 | Seawater equation of state relating density to temperature, salinity, and pressure for computing ocean buoyancy and circulation. | \rho = \rho(S, T, P) |
OC13 | Streamfunction for incompressible flow defining velocity components such that mass conservation is automatically satisfied. | \Psi = \int \vec{u} \cdot d\vec{A} |
OC14 | Volume transport through an ocean section computed by integrating current velocity over the cross-sectional area. | Q = \int\int \vec{u} \cdot \hat{n} dA |
OC15 | Tidal harmonic analysis decomposing sea level variations into constituent sinusoidal components with known astronomical frequencies. | \eta_{tide} = \sum_i H_i\cos(\omega_i t + \phi_i) |
OC2 | Deep-water surface gravity wave phase speed depending on wavelength and gravitational acceleration through the dispersion relation. | c = \sqrt{\frac{g\lambda}{2\pi}\tanh\frac{2\pi H}{\lambda}} |
OC3 | Wave breaking height criterion estimating the maximum stable wave height as a fraction of the local water depth. | H_b = 0.78 H_s |
OC4 | Shallow water wave equations governing long-wave propagation where wave speed depends on the square root of depth times gravity. | \frac{\partial\eta}{\partial t} + \nabla \cdot (H\vec{u}) = 0 |
OC5 | Ekman transport giving the net horizontal mass transport in the wind-driven ocean surface layer directed perpendicular to the wind stress. | \vec{u}_E = \frac{\vec{\tau}}{\rho f D_E} |
OC6 | Ekman layer depth estimating the thickness of the wind-driven surface layer from vertical eddy viscosity and the Coriolis parameter. | D_E = \sqrt{\frac{2A_v}{f}} |
OC7 | Coriolis parameter as a function of latitude, quantifying the deflective effect of Earth's rotation on moving fluid parcels. | f = 2\Omega\sin\phi |
OC8 | Geostrophic current velocity derived from the balance between the horizontal pressure gradient and the Coriolis force in the ocean. | \vec{u}_g = \frac{1}{\rho f}\hat{k} \times \nabla P |
OC9 | Rossby number comparing inertial to Coriolis forces, indicating whether rotation or advection dominates the flow dynamics. | Ro = \frac{U}{fL} |
Compute with one of these
curl -sS -X POST https://zeqsdk.com/api/zeq/compute \
-H "Authorization: Bearer $ZEQ_KEY" \
-H "Content-Type: application/json" \
-d '{"operators":["GP1"],"inputs":{}}'
The response carries the bare physics value, its unit and uncertainty, the generated master equation, and a signed envelope you can verify on any node.
See also
- The solvers — how an operator becomes a physical answer
- Operator selection — how a query picks operators
- All categories — the full reference index