Lithological control on regolith thickness across the Southern Granulite Terrain: an open multi-district compilation of CGWB NAQUIM exploratory-well lithologs

An open, provenance-tracked compilation of 1,929 Central Ground Water Board (CGWB) NAQUIMexploratory-well lithologs across the Southern Granulite Terrain of southern India (Kerala 510, TamilNadu 1,190, Karnataka 229), with depth to bedrock, harmonised lithology, coordinates and quality-controlflags. The wells are classified against a tectonic boundary traced from the published map of Das andRai (2019, Precambrian Research 332, 105394): 1,039 fall inside the terrain, and 717 (291 charnockite,426 gneiss-metasediment) meet the inclusion rules for a pre-registered test of lithological control ondepth to bedrock. The deposit includes the master table, the GLO-30 terrain-covariate join, the tracedboundary shapefile and its georeferenced source, a single-command reproduction script with a pinnedenvironment and a clean-run log, and the confirmatory results and manuscript tables. All spatial dataare in WGS 84 (EPSG:4326). This version enlarges the earlier compilation with the southern Tamil Nadu harvest and adds thetectonic-boundary classification and the terrain-restricted analysis. Keywords: Southern Granulite Terrain; depth to bedrock; regolith thickness; charnockite; gneiss;CGWB NAQUIM; exploratory wells; SoilGrids; Pelletier; open data; India.