The downunder module provides a collection of high-level tools for 3D inversion of geophysical data using the finite element method. The tool kit is based on the escript module for numerical modeling which, through its python-based user interface, provides a convenient high-level interface to build complex inversions and at the same time to make efficient use of desktop computers and HPC facilities with thousands of cores.

Contributor: Lutz Gross, University of Queensland
e: l.gross@uq.edu.au

REDBACK is a software for efficient reduction of noise in finite-rotation datases for plate kinematic reconstructions. It has been developed at the Research School of Earth Sciences of the Australian National University, as part of the AuScope–AGOS Inversion Laboratory.

Contributors: Giampiero Iaffaldano, Rhys Hawkins, Thomas Bodin, University of California Berkeley and Malcolm Sambridge.
e: Giampiero Iaffaldano <giia@ign.ku.dk>

This is a Fortran90 or C callable software library for exhaustively searching a multidimensional (hyper) cube or hyper sphere in arbitrary numbers of dimensions in parallel. It can be used to perform enumerative search of a parameter space with either simple bounds on each parameter (leading to a hyper-cube) or bounds on the norm of the spatial position (leading to a hyper-sphere). It can also perform Monte Carlo integration of a supplied function using uniform random points generated in a series of nested hyper-cubes.

Contributor: Malcolm Sambridge
e: Malcolm.Sambridge@anu.edu.au

This library provides routines for running Reversible Jump Monte-Carlo Markov chains for 1-D and 2-D spatial regression problems. It also allows generalization to any spatial 1-D and 2-D problem through the users inclusion of a forward model. The routines here are used as the basis of problem specific applications such as Receiver function inversion and 2-D travel time tomography.

Contributors: Rhys Hawkins, Thomas Bodin, University of California Berkeley and Malcolm Sambridge
e: Malcolm.Sambridge@anu.edu.au

This is a Fortran90 source code for multi-dimensional optimization (derivative free) and probabilistic sampling. Parallel Tempering is a technique for accelerating convergence of Markov chains in multi-dimensional sampling. It can be used for Bayesian probabilistic sampling or optimization (misfit function fitting).

Contributor: Malcolm Sambridge
e: Malcolm.Sambridge@anu.edu.au

The iDAD software was developed as a GUI interface implementing the algorithms for Uranium series dating of bone in an open system.

Contributor: Malcolm Sambridge
e: Malcolm.Sambridge@anu.edu.au

The neighbourhood algorithm is a two-stage numerical procedure for non-linear geophysical inverse problems. It also has applications as a direct search technique for global optimization.

Contributor: Malcolm Sambridge
e: Malcolm.Sambridge@anu.edu.au

Change Point modelling on multiple data sets (with or without unknown errors)

Contributor: Kerry Gallagher, Université de Rennes.
e: kerry.gallagher@univ-rennes1.fr

Transdimensional inverse thermal history modeling for quantitative thermochronology using a Bayesian transdimensional Markov Chain Monte Carlo method.

Contributor: Kerry Gallagher, Université de Rennes.
e: kerry.gallagher@univ-rennes1.fr

For mixture modelling (identification of an unknown number component distributions in a set of measurements, typically represented as a histogram)

Contributor: Kerry Gallagher, Université de Rennes.
e: kerry.gallagher@univ-rennes1.fr

NN-QUICK is an X-interface for the natural neighbour subroutines written by Malcolm Sambridge and Jean Braun of the Research School of Earth Sciences at the Australian National University from May 1994 to Oct. 1995.

Contributor: Malcolm Sambridge
e: Malcolm.Sambridge@anu.edu.au

Python library and example program which implements techniques for estimating principal absorbances of geological materials from unpolarised spectroscopic measurements.

Contributors: Malcolm Sambridge (ANU) and Andrew Jackson (ETH).
e: Malcolm.Sambridge@anu.edu.au, Andrew.Jackson@erdw.ethz.ch

2D trans-dimensional inference with Voronoi cells and two alternative underlying parameterizations.

Contributors: Rhys Hawkins, Malcolm Sambridge (ANU), et.al.
e: Rhys.Hawkins@anu.edu.au

Attenuation Tomography of the outer layer of the Earths inner core using Spherical Voronoi cells in a shell to perform Trans-D tomography. The underlying code structure is equally applicable to any form of tomographic reconstruction in a spherical shell where the observation is a line integral over a known (seismic) raypath.

Contributors: Tanja Pejić, Rhys Hawkins, Malcolm Sambridge & Hrvoje Tkalčić
e: Rhys.Hawkins@anu.edu.au

This is software for inversion of seismic Receiver Functions for 1-D Shear wave velocity structure using Reversible jump Markov chain Monte Carlo algorithm. In this algorithm the number of layers in the model is unknown as are the interface depths between layers and the Vs wave velocity in each layer. The algorithm results in an ensemble of solutions and properties of the ensemble may be generated for inspection.

Contributors: Rhys Hawkins and Thomas Bodin, University of California Berkeley
e: Thomas.Bodin@berkeley.edu

This code computes 2D Travel Time Tomography using the Reversible Jump algorithm with a Voronoi cell parameterisation. The software inverts for the velocity profile over a 2D rectangular region defined by longitude/latitude coordinates based on observed travel times, for example, for Ambient noise tomography. It also estimates the error paremeter.

Contributors: Rhys Hawkins and Thomas Bodin, University of California Berkeley
e: Rhys.Hawkins@anu.edu.au

For seismic arrival time residual estimation and array beamforming.

Contributors: Nick Rawlinson, University of Cambridge and Brian Kennett
e: nr441@cam.ac.uk

3-D wavefront tracking for tracking phases comprising any number of reflection and transmission branches in complex layered media. Uses fast marching to compute traveltimes, and can also generate raypaths and Frechet derivatives.

Contributor: Nick Rawlinson, University of Cambridge
e: nr441@cam.ac.uk

FMTOMO performs 3-D traveltime tomography to map a variety of traveltime datasets (e.g. local earthquake, teleseismic, reflection, wide-angle) as 3-D variations in seismic wavespeed and interface structure. It uses the fast marching method (FMM) for the forward step of traveltime prediction, and a subspace inversion scheme to adjust model parameters in order to satisfy data observations.

Contributor: Nick Rawlinson, University of Cambridge
e: nr441@cam.ac.uk

A spherical shell (surface wave) tomography code for mapping traveltime residuals as 2-D variations in wavespeed.

Contributor: Nick Rawlinson, University of Cambridge
e: nr441@cam.ac.uk

A teleseismic tomography code for mapping relative arrival time residuals as 3-D variations in wavespeed beneath a seismic array.

Contributor: Nick Rawlinson, University of Cambridge
e: nr441@cam.ac.uk

Tomographic model visualisation software. Tomoeye can also be used to visualize the distribution of any three-dimensional fields in the Earth

Contributors: Alexei Gorbatov and Ajay Limaye
e: Ajay.Limaye@anu.edu.au

TRABOX is an initial value and bounday vlaue (i.e. two-point) seismic ray tracing program in Cartesian co-ordinates

Contributor: Malcolm Sambridge
e: Malcolm.Sambridge@anu.edu.au

The Interactive Receiver Function Forward Modeller is an interactive Java program for joint interactive forward modelling of teleseismic receiver functions and surface wave dispersion.

Contributor: Hrvoje Tkalčić
e: hrvoje.tkalcic@anu.edu.au