structr is a free and open-source package for R that provides tools for structural geology. You can
analyze and visualize orientation data of structural geology (including, stereographic projections, contouring, fabric plots, and statistics),
do a cluster analysis of orientation data,
analyze stress (including visualization of the magnitudes of stress in the Mohr circle and extracting the maximum horizontal stress of a 3D stress tensor),
reconstruct the orientation of structures in oriented drill cores using the alpha, beta, and gamma angles,
calculate fault displacement components,
reconstruct orientation and magnitudes using fault-slip inversion (Paleostress analysis),
contour geologic fabric and finite strain data (Rf/ϕ) on the unit hyperboloid,
perform vorticity analysis using the Rigid Grain Net method, and
directly import your field data from StraboSpot.
The {structr} package is all about structures in 3D. For analyzing orientations in 2D (statistics, rose diagrams, etc.), check out the tectonicr package!
Installation
You can install the development version of structr from GitHub with:
# install.packages("devtools")
devtools::install_github("tobiste/structr")Example
This is a basic example which shows you how to import data and plot them on stereographic or equal-area projections.
library(structr)
library(ggplot2)
library(mapproj)
data(example_planes)
planes <- Plane(example_planes$dipdir, example_planes$dip)
fabric <- or_shape_params(planes)$Vollmer["D"]
ggstereo() +
geom_contourf_stereo(gg(planes)) +
geom_point(data = gg(planes), aes(x, y), color = "grey", shape = 21) +
scale_fill_viridis_d(option = "F") +
labs(
subtitle = "Example data",
title = "Density contour plot",
fill = "Multiples of\nvon Mises-Fisher\ndistribution",
caption = paste0("Equal area, lower hemisphere projection | N: ", nrow(planes), " | Fabric strength: ", round(fabric, 2))
)
Documentation
The detailed documentation can be found at https://tobiste.github.io/structr/
Author
Tobias Stephan (tstephan@lakeheadu.ca)
Feedback, issues, and contributions
I welcome feedback, suggestions, issues, and contributions! If you have found a bug, please file it here with minimal code to reproduce the issue.