Probabilistic Sediment Stability Pipeline for IODP Multi-Expedition Analysis
ProboSed is a Python pipeline for extracting Fabric Preservation Index (FPI) scores and process flags from IODP Visual Core Description PDFs, and for running stochastic slope stability models calibrated from those scores. It supports cross-margin comparison across passive and convergent margin settings using data from IODP Expeditions 308, 386, and 405.
Slope displacement
Slope failure is defined as a first-passage problem:
where the failure threshold
| FPI | Label | Physical meaning | Failure threshold |
|---|---|---|---|
| 3 | Intact | Primary fabric fully preserved | 2.00 |
| 2 | Partially preserved | Minor disruption, fabric recognizable | 1.33 |
| 1 | Fabric destroyed | Scaly/shear surfaces, original fabric lost | 0.67 |
| 0 | Structureless | No fabric, homogeneous or fluidized | 0.00 |
Process flag: T = Tectonic · G = Gravitational · D = Depositional · F = Fluid escape · U = Undetermined
MTD-context rule: fault terms appearing within mass-transport context are downgraded T -> G. Faults within MTDs are soft-sediment features, not tectonic structures.
| Parameter | Value | Physical basis |
|---|---|---|
| 0.6 | Frontal prism |
|
| 1.0 | Moderate restoring force; 1.5–2.0 for seismically strengthened sediment (Exp 386) | |
| 0.5 |
|
|
slip_mag |
3.0 | Scaled from ~50 m coseismic slip at C0019 décollement (Fulton et al. 2013) |
ProboSed/
├── notebooks/
│ ├── ProboSed_VCD_FPI_Catalog.ipynb
│ ├── ProboSed_Stochastic_Slope_Stability_Model.ipynb
│ ├── ProboSed_Parameter_Sensitivity_Analysis.ipynb
│ ├── ProboSed_Porewater_Geochemistry_Profiles.ipynb
│ ├── ProboSed_MTD_Physical_Property_Quantification.ipynb
│ ├── ProboSed_XRF_Geochemical_Lithology_Profile.ipynb
│ ├── ProboSed_LWD_Physical_Property_Analysis.ipynb
│ ├── ProboSed_Failure_Probability_vs_Depth.ipynb
│ ├── ProboSed_Core_Image_Patch_Extractor.ipynb
│ ├── ProboSed_Block_Size_Distribution_Imagery.ipynb
│ ├── ProboSed_Block_Size_Distribution.ipynb
│ ├── ProboSed_Core_Image_Texture_Analysis.ipynb
│ ├── ProboSed_VCD_Labeler.ipynb
│ ├── ProboSed_Stochastic_Forcing_Model.ipynb
│ ├── ProboSed_XCT_Density_Integration.ipynb
│ ├── ProboSed_Resistivity_Image_Panels.ipynb
│ ├── ProboSed_Structural_Mask_vs_Stress.ipynb
│ ├── ProboSed_Sediment_Stability_Pipeline.ipynb
│ └── ProboSed_Pipeline_Summary_Figures.ipynb
│
├── slope/
│ ├── __init__.py
│ ├── stability.py Core physics -- OU model, Lyapunov, sensitivity
│ ├── toy_model.py Standalone simulation script
│ └── sensitivity_run.py Sensitivity analysis script
│
├── core_ml/
│ ├── __init__.py
│ └── labeler.py JCORESMiner, StraterMiner, Exp386Miner, VCDLabeler
│ FPI_LEXICON, PROCESS_FLAG_LEXICON
│
├── geochem/
│ ├── __init__.py
│ └── geochem_analysis.py Porewater and headspace gas depth profiles
│
├── transport/
│ ├── __init__.py
│ └── agents.py Agent-based sediment transport ensemble
│
├── utils/
│ ├── __init__.py
│ └── patcher.py Core image patch extraction utility
│
├── requirements.txt
├── pyproject.toml
├── CITATION.cff
├── LICENSE
└── README.md
All notebooks are designed to run in Google Colab without local installation. Each notebook imports from the slope/, core_ml/, geochem/, transport/, and utils/ modules -- the .py files are the source of truth and the notebooks are interactive wrappers.
Run order for dissertation analysis: 01 → 02 → 03 → remaining notebooks in any order.
| Notebook | Purpose | Key outputs |
|---|---|---|
| VCD_FPI_Catalog | Parses VCD PDFs from Expeditions 308, 386, and 405 using OCR (tesseract) and three expedition-specific miners (StraterMiner, Exp386Miner, JCORESMiner). Assigns a two-axis classification: Fabric Preservation Index (FPI 0--3) and process flag (T/G/D/F/U) to each depth interval. Builds the multi-expedition deformation facies catalog. Run before all other notebooks. | fpi_catalog_all_expeditions.csv, fpi_catalog_exp308.csv, fpi_catalog_exp386.csv, fpi_catalog_exp405.csv, fpi_summary_stats.csv, deformation_facies_catalog.csv, FPI_expedition_comparison.pdf, FPI_depth_profiles.pdf |
| Stochastic_Slope_Stability_Model | Runs the coupled OU slope stability ensemble under slope-only and fault-coupled forcing. Cross-margin edition: derives sigma_q from public Vp data (PANGAEA MSCL for M0081; local CSV for Exp 308) and runs separate ensemble pairs for Expeditions 308 (passive), 386 (convergent), and 405 (convergent). Produces trajectory figures, cross-margin failure probability comparison, and Lyapunov exponent estimates. | slope_model_trajectories_crossmargin.png, slope_model_pfail_crossmargin.png, slope_model_lyapunov_crossmargin.png, slope_model_crossmargin_summary.csv |
| Parameter_Sensitivity_Analysis | One-at-a-time sensitivity analysis across physically motivated parameter ranges. Cross-margin edition: runs separately for each site's BASE parameters; uses FPI-anchored threshold values; per-site slope-only baselines replace hardcoded reference. Tests robustness of qualitative result across alpha, sigma_q, slip_mag, gamma, and theta for all three margins. | sensitivity_results_crossmargin.csv, sensitivity_robustness_crossmargin.csv, per-site sensitivity figures |
| Porewater_Geochemistry_Profiles | Five-panel porewater and headspace gas depth profiles for C0019J and C0019M. Overlays deformation intervals from the FPI catalog when the catalog CSV is available. | Three geochemistry figures |
| ProboSed_MTD_Physical_Property_Quantification | Statistical comparison (Mann-Whitney U) of resistivity, Vp, and porosity inside and outside FPI-derived deformation intervals. Validates that FPI captures real mechanical contrasts. | C0019J_MTD_statistics.csv, C0019J_MTD_properties.csv, depth profile and box plot figures |
| XRF_Geochemical_Lithology_Profile | Identifies the mafic geochemical discontinuity (SiO2 < 50 wt%) at 635.94 m CSF-A. Four-panel integrated physical and structural profile. | C0019J_XRF_profile.png, C0019J_integrated_profile.png |
| LWD_Physical_Property_Analysis | Loads the C0019H LWD LAS file and runs Mann-Whitney U comparisons of resistivity and Vp between deformed and intact intervals. | Statistical comparison table |
| Failure_Probability_vs_Depth | Monte Carlo failure probability versus depth using vane shear strength and MAD data. Quantile-based depth binning for sparse sampling. | Failure probability depth profile |
| Core_Image_Patch_Extractor | Sliding-window patch extraction from ruler-free core section photographs. Classifies patches using the FPI deformation catalog. | Patch archive, patch_manifest.csv |
| Block_Size_Distribution_Imagery | Block boundary detection from core photographs using brightness and lateral-variance signal. Power law fit to cumulative block size distribution. | C0019J_block_sizes_imagery.csv, distribution figures |
| Block_Size_Distribution | Block boundary detection from MSCL colorimetry L* profiles. Power law fit. | Block size distribution, power law fit |
| Core_Image_Texture_Analysis | GLCM texture metrics (contrast, correlation, energy, homogeneity), orientation statistics, and autocorrelation length from core image patches. | Texture metric depth profiles |
| VCD_Labeler | Interactive ipywidgets labeling interface for core image patches. Records fabric type, process flag, confidence, and notes. | C0019J_VCD_labels.csv |
| Stochastic_Forcing_Model | Two-component SDE model with optional SRCMOD Tohoku finite-fault slip-rate forcing. Compares response-only and seismically forced ensemble failure probabilities. | Ensemble figures, s_forcing.csv |
| XCT_Density_Integration | DICOM CT Hounsfield unit profiles per deformation interval from XCT scan data. | Density profiles by interval |
| Resistivity_Image_Panels | RAB resistivity image panel extraction for MTD-9 and MTD-10 from Hole C0019H. | Resistivity image panels |
| Structural_Mask_vs_Stress | Structural overprint flags versus Conin et al. JFAST/JTRACK borehole breakout stress data. | Structural-stress comparison figure |
| Sediment_Stability_Pipeline | Legacy -- retained for provenance only. Early VCD lexicon parser and geotechnical merge pipeline using the original single-axis stability score (0--3). Superseded by ProboSed_VCD_FPI_Catalog, which implements the two-axis FPI + process flag system. Do not use as part of the active analysis pipeline. | Stability depth profile (legacy) |
| Pipeline_Summary_Figures | Graphviz workflow diagram and two-panel mechanical regime depth profile. | Workflow diagram, regime figure |
ProboSed is designed for research in:
- Submarine landslides and mass-transport deposits
- Earthquake-triggered sediment transport at convergent margins
- Probabilistic slope stability modeling
- Marine sediment routing systems
- IODP core data integration with geophysical observations
Development uses core and logging data from the Japan Trench margin, IODP Expeditions 386 and 405, Site C0019.
Contributions are welcome. Please open an issue to discuss proposed changes before submitting a pull request.
MIT License — see LICENSE for details.
Development of ProboSed is part of doctoral research at The Ohio State University, School of Earth Sciences.
Advisors Dr. Brendan Crowell — Co-Advisor Dr. Jill Leonard-Pingel — Co-Advisor
Dissertation Committee Dr. Cole · Dr. Keep · Dr. Krissek
Field Science Dr. Christine Regalla — Co-Chief Scientist, IODP Expedition 405
Data This work uses data from the International Ocean Discovery Program (IODP), Expeditions 386 and 405, Japan Trench margin.
Chester, F.M., et al. (2013). Structure and composition of the plate-boundary slip zone for the 2011 Tohoku-oki earthquake. Science, 342(6163), 1208–1211.
Fulton, P.M., et al. (2013). Low coseismic friction on the Tohoku-oki fault determined from temperature measurements. Science, 342(6163), 1214–1217.
Valdez, R.D., et al. (2015). Data report: permeability and consolidation behavior of sediments from the northern Japan Trench subduction zone, IODP Site C0019. Proc. IODP, 343/343T.
Expedition 405 Scientists (2025). Site C0019. In Proc. IODP, 405.
Alstott, J., Bullmore, E., & Plenz, D. (2014). powerlaw: A Python package for analysis of heavy-tailed distributions. PLOS ONE, 9(1), e85777.
Haralick, R.M., Shanmugam, K., & Dinstein, I. (1973). Textural features for image classification. IEEE Transactions on Systems, Man, and Cybernetics, 3(6), 610–621.
If you use ProboSed, please cite:
Castillo, R. et al. (in prep). When Slip Happens: From Megathrust Rupture to Nonlinear Shallow Prism Reorganization in the 2011 Tohoku-Oki Earthquake. PhD dissertation, Ohio State University.
See also CITATION.cff for machine-readable citation metadata.