Disclaimer

FracSTAT is a research and analysis tool developed by, and for, the structural geology and rock-mechanics community. This page sets out, in plain terms, the limits of what the software and this documentation can responsibly claim to do.

On this page

1. No Warranty

As stated in the software's MIT License, FracSTAT is provided "as is," without warranty of any kind, express or implied — including, without limitation, any warranty of merchantability, fitness for a particular purpose, or non-infringement. The authors make no guarantee that the software is free of bugs, that any specific calculation is numerically exact in every edge case, or that any given release is fit for any specific project's requirements.

2. Not a Substitute for Professional Judgment

FracSTAT computes geometric statistics (length, orientation, connectivity, intensity), stress-resolution metrics (slip tendency, dilation tendency, fracture susceptibility, Mohr–Coulomb failure state), and uncertainty-quantification outputs from the data and stress assumptions a user supplies. Every output described throughout this documentation — for example the tendency and failure-state metrics explained on the Method Tab page, or the distribution-fitting results on the CDF Tab page — is conditional on the input geometry and stress model actually entered, and is intended as a decision-support aid, not a decision by itself. Interpretation of any result requires the judgment of a qualified structural geologist, geotechnical engineer, or geomechanics specialist familiar with the specific field area, dataset, and intended application.

3. Accuracy of Calculations and Statistics

Wherever practical, this documentation reproduces the exact formulas FracSTAT implements (for example, the Mohr–Coulomb stress-resolution equations, the Mauldon circular-scanline intensity/density estimators, and the maximum-likelihood distribution-fitting procedure used on the CDF tab) so that results can, in principle, be independently verified by hand or with separate software. Numerical results nonetheless depend on floating-point arithmetic, on the specific numerical tolerances and clamping rules documented in each tab's own page (e.g. the segment-intersection tolerances described on the Connectivity Tab page), and on any third-party library FracSTAT depends on (NumPy, SciPy, the powerlaw package, and others). Users performing safety- or economically-significant work are encouraged to cross-check key results against an independent calculation.

4. Dependence on Input Data Quality

Every statistic FracSTAT reports is only as reliable as the digitized trace map, Excel/CSV table, or calibrated photograph supplied to it. Digitization resolution, sampling-area edge-truncation and censoring effects, scale-calibration accuracy, and dip-override data quality (all discussed in their respective tab pages, e.g. the edge-censoring discussion on the Histogram Tab page) directly propagate into every downstream statistic, plot, and export. FracSTAT does not, and cannot, independently verify the geological accuracy of data a user chooses to load.

5. Safety-Critical and Regulatory Use

FracSTAT is not certified, warranted, or represented as suitable for any specific regulatory submission, safety case, reservoir-development decision, or engineering design without independent professional review. Any use of FracSTAT's outputs to inform decisions with safety, financial, or regulatory consequences — including but not limited to slope-stability assessments, injection-induced seismicity screening, or reservoir development planning — remains the sole responsibility of the practitioner and organization making that decision.

6. Accuracy of This Documentation

This documentation is maintained alongside the software and describes FracSTAT's behaviour to the best of the authors' knowledge at the time of writing. Because FracSTAT is under active development, a specific control, default value, or algorithmic detail described here may occasionally lag behind, or run ahead of, the exact behaviour of the version of FracSTAT you are running. When in doubt, the source code linked from the License page is the authoritative reference.

This site links to third-party resources — including Python's own download page, GitHub, and embedded YouTube/Google Drive videos on the Video Tutorials page. FracSTAT's authors do not control, and are not responsible for, the content, availability, or accuracy of any external site or service linked from these pages.

8. Limitation of Liability

To the fullest extent permitted by law, and consistent with the MIT License under which FracSTAT is distributed, the authors and their affiliated institutions (listed on the Introduction page) shall not be liable for any claim, damages, or other liability arising from, out of, or in connection with the software, this documentation, or the use of either.