# Relationship history for MSHA mine 2602224

Current hierarchy: **Halliburton Company → Brown & Root Inc → Corona Gold Project (Santa Fe Mines)**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Halliburton Company → Corona Gold Project (Santa Fe Mines); 1978-03-09 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Brown & Root Inc → Corona Gold Project (Santa Fe Mines); 1993-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Halliburton Company → Brown & Root Inc; 1993-02-01 to current/open; source msha-controller-operator-history