Karst & Depressions
Two measured surfaces a sinkhole assessment would want as inputs — deliberately not a sinkhole probability. Measured in Florida, depression depth scores AUC 0.649 [0.58, 0.71]: 51% of verified sinkholes sit in a closed depression against 24% of confirmed non-sinkholes. Validation is Florida-only, and Florida is atypical karst (sand over carbonate). ⚠ The brightest terrain in the depth band is endorheic basins, not karst — interpret regionally, never globally.
What ships in the bundle
2 global 90 m (3 arcsec) GeoTIFFs (~6.7 GB total) plus the full documentation set. All files are Cloud-Optimized GeoTIFFs with internal tiling and overviews — fast for both bulk download and windowed reads.
Method
Inputs · GEDTM30 v1.2 bare-earth DEM (CC BY 4.0) + GLiM lithology (CC BY)
Training labels · Florida DEP Subsidence Incident Reports — validation only, never an input
Method · Priority-flood sink fill (Wang & Liu 2006) on GEDTM30 bare earth, filled to true pour points with a 256 px halo; GLiM lithology reclassed to a solubility ordinal
Documentation
Open — no account needed. The data below requires a free API key.
- README — entry point + quick start
- Methodology — how the model was built
- Model card — intended use, biases, limitations
- Data sources — input data citations
- Validation report — accuracy + known limitations
- Changelog — vintage evolution
- Licence — terms of use for this layer
- Citation — how to cite this dataset
- API usage — code snippets
- Bulk download — fetching the whole bundle
Download
Free for academic, research, and other non-commercial use. Account required.
# $PETREL_API_KEY = your API key (tlk.…) from the dashboard — free tier works.
# 1. Fetch 1-hour signed URLs for every file in the bundle:
curl -s -H "X-API-Key: $PETREL_API_KEY" \
https://api.petreldata.io/v1/layer/karst_depressions/v0.1/bundle > bundle.json
# 2. Download the full layer (~6.7 GB):
mkdir -p karst_depressions_v0.1
jq -r '.files[] | [.url, .name] | @tsv' bundle.json | \
while IFS=$'\t' read -r url name; do
curl -s "$url" -o "karst_depressions_v0.1/$name"
doneLicense & citation
License: CC-BY-NC-4.0. Free for academic, research, and other non-commercial use. For commercial licensing, contact petreldata.io@gmail.com.
Citation:
Petrel (2026). Petrel Karst & Depressions v0.1.
https://petreldata.io/layers/karst_depressions
CC-BY-NC-4.0Version history
- karst_depression_depth_90m.tif — depth below the sink-filled bare-earth surface (GEDTM30, filled to each depression's lowest pour point). Zero where the pixel drains. Validated in Florida against 103 verified sinkholes and 108 confirmed non-sinkholes: AUC 0.649 [0.58, 0.71], i.e. 51% of verified sinkholes sit in a closed depression against 27% of confirmed non-sinkholes.
- karst_solubility_90m.tif — GLiM bedrock dissolution class (0 insoluble, 1 possible, 2 carbonate, 3 evaporite). Shipped as context; it does not discriminate in Florida (AUC 0.520) because the surficial geology there is sand over carbonate.