Coal resource data for coalbed methane (CBM) assessment in Crawford County, Illinois and surrounding counties.
This repository contains drill hole data and analysis scripts for evaluating CBM potential in a 6-county study area in southeastern Illinois. The data supports a pre-drilling assessment before committing to a $920K drilling program.
Study Area Counties: Crawford, Clark, Lawrence, Jasper, Cumberland, Richland
Explore drill hole locations and coal seam data with interactive HTML maps:
| Map | Description |
|---|---|
| All Seams Combined | Overview of all coal seams |
| Herrin Coal | Herrin (No. 6) Coal drill holes |
| Springfield Coal | Springfield (No. 5) Coal drill holes |
| Danville Coal | Danville (No. 7) Coal drill holes |
| Colchester Coal | Colchester (No. 2) Coal drill holes |
| Seelyville Coal | Seelyville Coal drill holes |
Explore coal seams in 3D with depth-accurate subsurface rendering:
| View | Description |
|---|---|
| 3D Terrain View | Rotatable 3D view of all seams below surface |
| Cross-Section (E-W) | East-West vertical slice through the study area |
| Cross-Section (N-S) | North-South vertical slice |
| Cross-Section (NW-SE) | Diagonal transect |
| Seam | Thickness Map | Depth Map | Histogram |
|---|---|---|---|
| Herrin |  |
 |
 |
| Springfield |  |
 |
 |
| Danville |  |
 |
 |
| Colchester |  |
 |
 |
| Seelyville |  |
 |
 |
To regenerate visualizations:
# 2D maps and plots
python visualize_coal_data.py
# 3D visualizations
python visualize_3d.py
# 3D with custom settings
python visualize_3d.py --exag 20 # 20x vertical exaggeration
python visualize_3d.py --skip-3d # Only generate cross-sections
python visualize_3d.py --transect-start "-88.0,39.0" --transect-end "-87.5,39.0"# Generate summary statistics
python3 summarize_coal_data.py
# Filter datasets to study area (already done)
python3 filter_study_area.py| Dataset | Records | Coverage |
|---|---|---|
| Major Coals (statewide) | 58,463 | Danville, Herrin, Springfield |
| Major Coals (study area) | 2,854 | 6-county filtered |
| Minor Coals (statewide) | 12,604 | Colchester, Seelyville, etc. |
| Minor Coals (study area) | 2,419 | 6-county filtered |
| Crawford County | 826 | 414 major + 412 minor |
- Best CBM Target: Springfield Coal - 78% of Crawford County records in optimal 500-1000 ft depth range
- Herrin Coal (No. 6): Primary target, thickest seam with best data coverage
- Data Gap: No direct gas content measurements exist - core sampling required
coalgas/
├── README.md # This file
├── DATA_SOURCES.md # Complete data acquisition guide
├── filter_study_area.py # Script to filter data to 6 counties
├── summarize_coal_data.py # Generate summary statistics
├── visualize_coal_data.py # Generate 2D maps and plots
├── visualize_3d.py # Generate 3D terrain and cross-section views
├── examples/ # Sample data files (50 rows each)
├── visualizations/
│ ├── interactive/ # Interactive HTML maps (Folium)
│ └── static/ # PNG plots (thickness, depth, histograms)
├── data/
│ ├── csv/ # Processed CSV files (68 MB)
│ └── downloads/ # Source data files (132 MB)
└── thoughts/shared/
├── plans/ # Implementation plan
└── handoffs/ # Handoff documentation
| File | Records | Description |
|---|---|---|
all-coals-study-area-combined.csv |
2,854 | Main analysis file - merged major/minor coal data |
major-coals-all-study-area.csv |
2,854 | Danville, Herrin, Springfield for 6 counties |
minor-coals-all-study-area.csv |
2,419 | Colchester, Seelyville for 6 counties |
| File | Records | Description |
|---|---|---|
major-coals-all.csv |
58,463 | All Illinois major coal drill holes |
minor-coals-all.csv |
12,604 | All Illinois minor coal drill holes |
| File | Records | Content |
|---|---|---|
herrin-depth.csv |
3,904 | Herrin Coal depth contours |
herrin-thickness.csv |
853 | Herrin Coal thickness contours |
springfield-depth.csv |
3,089 | Springfield Coal depth contours |
springfield-thickness.csv |
702 | Springfield Coal thickness contours |
danville-depth.csv |
112 | Danville Coal depth contours |
danville-thickness.csv |
416 | Danville Coal thickness contours |
colchester-depth.csv |
261 | Colchester Coal depth contours |
colchester-thickness.csv |
302 | Colchester Coal thickness contours |
seelyville-depth.csv |
50 | Seelyville Coal depth contours |
seelyville-thickness.csv |
69 | Seelyville Coal thickness contours |
IDS - Unique drill hole identifier
COUNTY_NAME - County name (CRAWFORD, CLARK, etc.)
LONGITUDE - WGS84 longitude (decimal degrees)
LATITUDE - WGS84 latitude (decimal degrees)
SURFELV - Surface elevation (ft above sea level)
WELL_TYPE - Well classification
LOG_TYPE - Type of log data available
# Major coals (Danville, Herrin, Springfield)
TOP_DANVILLE, THICK_DANVILLE - Danville Coal elevation & thickness
TOP_HERRIN, THICK_HERRIN - Herrin Coal elevation & thickness
TOP_SPRING, THICK_SPRING - Springfield Coal elevation & thickness
# Minor coals (in minor-coals files)
TOP_COLCH, THICK_COLCH - Colchester Coal elevation & thickness
TOP_SEELY, THICK_SEELY - Seelyville Coal elevation & thickness
Note: TOP_* values are elevations (ft above sea level), not depths from surface. Calculate actual depth: SURFELV - TOP_*
Filters statewide drill hole data to the 6-county study area.
- Uses county name filtering (primary) or bounding box fallback
- Outputs
*-study-area.csvfiles - Uses only Python stdlib (
csvmodule) - no pandas required
Generates summary statistics for CBM assessment.
- Calculates depth/thickness ranges per seam
- Shows Crawford County-specific statistics
- Creates combined CSV merging major and minor coal data
- Outputs CBM potential assessment summary
Generates 3D coal seam visualizations.
- 3D terrain view (pydeck): Rotatable 3D map with drill holes as columns and seam intersections at depth
- Cross-section views (Plotly): Vertical slices showing surface profile and coal seam layers
- Configurable vertical exaggeration (default 10x)
- Custom transect lines supported via CLI arguments
- Outputs standalone HTML files with interactive controls
| Document | Description |
|---|---|
2025-01-04-crawford-county-cbm-data-acquisition.md |
Full implementation plan with verification steps |
2025-01-04-cbm-data-acquisition-handoff.md |
Handoff notes and context |
The examples/ directory contains sample files (50 rows each) for quick inspection:
| File | Description |
|---|---|
major-coals-sample.csv |
Sample major coals drill hole data |
minor-coals-sample.csv |
Sample minor coals drill hole data |
herrin-depth-sample.csv |
Sample Herrin Coal depth contours |
See DATA_SOURCES.md for complete download instructions and data documentation.
Quick Links:
- ILMINES Wiki: https://ilmineswiki.web.illinois.edu/
- Major Coals Dataset: 58,000+ drill holes
- Minor Coals Dataset: 12,000+ drill holes
- Coal Shapefiles: Illinois Coal Resource Shapefiles
Large binary files are excluded via .gitignore:
data/downloads/*.zip- Downloaded ZIP archives (132 MB)data/shapefiles/- Extracted shapefile data (176 MB)data/reference-pdfs/- PDF maps for visual reference
To regenerate these files, follow the download instructions in the implementation plan.
For coalbed methane, the "sweet spot" is typically 500-1000 ft from surface:
- Too shallow (<500 ft): Insufficient pressure to hold methane
- Too deep (>1000 ft): Reduced permeability, higher drilling costs
No direct gas content measurements exist for Crawford County. This cannot be resolved through public data - core sampling is required as Phase 1 of the drilling program.
ISGS Coal Section: ilmines@isgs.illinois.edu, 217-244-2414
Data sourced from public Illinois State Geological Survey resources.