Stereonet3D (previously OSXStereonet) plots lines and planes in spherical, equal angle or equal area, projections. The program can produce various types of plots such as scatter plots, great or small circle plots, arc segments, contour diagrams, rose diagrams, stereonets from any view direction, plots of latitude-longitude data (e.g. coastlines), afull screen 3D view of the spherical projection and data, and a Map/Satellite view of data with lat-long information.
In addition, the program can perform various operations, including calculating poles to planes, rotating planes and lines, constraining lines to lie on their respective planes, angle between lines or planes, cylindrical best fit, conical best fit, and mean vector. Data with lat-long information can be exported to Google Earth.
Stereonet3D runs only on OSX 10.9 (Mavericks). It is available on the Mac App Store for 4.99 USD. To test the program's Map view and export to kml, here is one file with strike/dip data from the Big Elk anticline in SE Idaho (right click to download and open it with the program's File -> Load Dataset from txt menu).
Structural geology deals to a great extent with the operation of vectors and tensors. GeoCalc (previously OSXGeoCalc) is a calculator for vectors (lines, planes, and oriented drillcore data), and tensors (strain and stress).
Lines and planes can be visualized in a stereonet, and strain and stress in a Mohr diagram. Multiple computations can be executed using text files. Besides being a great tool to learn the fundamental concepts of vectors and tensors and their application in structural geology, GeoCalc is a powerful tool to perform batch operations on thousands of vectors or tensors stored in text files.
GeoCalc was made for structural geologists, but it can be used by anyone interested in vectors and tensors. GeoCalc runs on Mac OSX 10.7 or later. It is available on the Mac App Store for 2.99 USD.
SSPX is a program to calculate strain/strain rate from displacement/velocity data in two and three dimensions. SSPX is a full fledged inverse modelling program to calculate best fitting deformation tensors given displacement or velocity vectors.
SSPX works equally well on small deformation problems such as computing strain rates from GPS data, or large deformation problems such as computing finite strain in a highly deformed discrete element model (DEM). SSPX can process single files, or batch process a group of sequential files. SSPX was made for geologists, but it can be used by anyone interested in computing strain/strain rate from displacement/velocity data.
More information about SSPX can be found in Cardozo and Allmendinger (2009). SSPX runs on Mac OSX 10.7 or later. It is available on the Mac App Store for 4.99 USD.
Trishear3D is a program to run 3D, forward trishear models. The program is based on the pseudo-3D algorithm of Cristallini and Allmendinger (2001), and the true-3D algorithm of Cristallini et al. (2004). Trishear3D can model the geometry and finite strain of compressional and extensional fault propagation folds, fault bend folds, rollovers, and lateral propagating faults. More information about Trishear3D, its algorithms and implementation can be found in Cardozo (2008).
Geometry and strain data can be visualized in a 3D plot which can be sliced along any orientation and queried for strain. Geometry and strain are also displayed in tables which can be easily exported. Trishear3D is a great tool to investigate the effects of temporal and spatial variations of fault parameters on the 3D geometry and strain field of fault related folds.
Trishear3D runs on Mac OSX 10.7 or later. The program is freeware for non-profit purposes (for consulting please contact me).
The subsidence of a sedimentary basin can be attributed to three processes: tectonic subsidence, water and sediment loading, and sediment compaction. These three components of subsidence can be estimated from a stratigraphic section using a procedure called "backstripping" (Allen and Allen, 1990). Backstripping removes from each sedimentary layer the effects of sediment compaction and water and sediment loading; thus extracting from the stratigraphic section the tectonic subsidence curve.
Backstrip (previously OSXBackstrip) is a program to perform "1D Airy backstripping with exponential reduction of porosity". Stratigraphic units can be easily input in a table, and backstripping and tectonic subsidence plots and tables can be rapidly produced. Plots can be edited or saved for publication. Multiple documents (stratigraphic sections) can be backstripped and compared.
Backstrip runs on Mac OSX 10.7 or later. The program is freeware for non-profit purposes (for consulting please contact me).
The displacement profile of the surface of the earth under crustal loads (e.g. mountain chains) can be well reproduced by an elastic flexural model. In this model, the uppermost layer of the earth (i.e. the elastic lithosphere) responds to crustal loads as an elastic beam, floating in a weaker, fluid-like foundation (i.e. the astenospheric mantle, Turcotte and Schubert, 1982).
Flex2D (previously OSXFlex2D) is a program that implements the elastic flexural model in 2D for a plate of constant or variable elastic thickness. Crustal loads can be entered and plotted, and the profile of deformation produced by these loads can be computed and visualized in plots and tables. Plots can be edited or saved for publications. Multiple load profiles can be computed and compared.
Flex2D runs on Mac OSX 10.7 or later. The program is freeware for non-profit purposes (for consulting please contact me).