Mineos.jl

Mineos.jl is a Julia wrapper around the Mineos programs to compute normal modes of the Earth and similar planets.

In Julia, simply do

julia> import Pkg; Pkg.add("Mineos")

The package relies on the SeisModels.jl package to create models for computation by Mineos. This will be installed if you follow the instructions above. However, to directly use the functionality of SeisModels.jl to create models, you need to add it to your environment using Pkg.add("SeisModels").

This is done using the eigenmodes function, which accepts a SeisModel.LinearLayeredModel. For example, to compute the frequency of ₀S₉ in PREM, ignoring toroidal modes and limiting the calculation to a maximum angular order of 9 and radial order of 0, you can do:

julia> using Mineos, SeisModels

julia> modes = eigenmodes(LinearLayeredModel(PREM), lmax=9, nmax=0, toroidal=false, ic_toroidal=false);

julia> modes[0,:S,9].frequency
1.578258

eiegenmodes returns a type (Mineos.Mode) which contains the following fields you can access:

• type: Type of oscillation, which is one of:
  • :spheroidal: Spheroidal mode
  • :toroidal: Toroidal mode
  • :ic_toroidal: Toroidal mode in the inner core
• n: Radial order
• l: Angular order
• phase_vel: Phase velocity of mode in km/s
• group_vel: Group velocity of mode in km/s
• frequency: Frequency of mode in mHz
• period: Period of mode in s
• Q: Attenuation of mode
• rayleigh_quotient: Rayleigh quotient of mode, which is the ratio of kinetic to potential energy minus one, which should be of order eps if the eigenfunction is accurate, where eps is the nominal error of the calculation integration scheme.

Note that you access mode _nX_l by modes[n,X,l], where n is the radial order, l is the angular order and X is :S for spheroidal or radial modes, :T for toroidal modes and :C for inner core toroidal modes. (See that X is a Symbol and therefore needs the : before the character.)

See the help for eigenmodes for a full list of keyword arguments.

The eigenfrequencies function is similar to eigenmodes, but only returns eigenfrequencies for each mode in mHz.

The retrieval of eigenfunctions and calculation of synthetic seismogramss are not yet implemented, but are planned for the future. Pull requests adding this functionality are welcome.

If you find a problem with this Julia wrapper of Mineos, then please open an issue with as much description as possible to recreate the error.

If you would like to contribute code which implements new functionality or fixes bugs in Mineos.jl, please submit a pull request or get in touch.