# Relationship history for MSHA mine 4606667

Current hierarchy: **Occidental Petroleum Corp → Island Creek Coal Company → Perry Fork No 1**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Occidental Petroleum Corp → Perry Fork No 1; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Black Hawk Resources Inc → Perry Fork No 1; 1983-05-01 to 1987-04-23; source msha-controller-operator-history
- **controller_controls_mine:** Compton Lucky D → Perry Fork No 1; 1983-05-01 to 1987-04-23; source msha-controller-operator-history
- **controller_controls_operator:** Compton Lucky D → Black Hawk Resources Inc; 1983-05-01 to 1987-04-23; source msha-controller-operator-history
- **operator_operates_mine:** Island Creek Coal Company → Perry Fork No 1; 1987-04-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Occidental Petroleum Corp → Island Creek Coal Company; 1987-04-24 to current/open; source msha-controller-operator-history