# Relationship history for MSHA mine 4604631

Current hierarchy: **Sanson Herschel → H & J Coal Company → 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Occidental Petroleum Corp → No 1; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Martin-Parsley Mining Company Inc → No 1; 1975-06-01 to 1977-03-06; source msha-controller-operator-history
- **controller_controls_mine:** Parsley Conley → No 1; 1975-06-01 to 1977-03-06; source msha-controller-operator-history
- **controller_controls_operator:** Parsley Conley → Martin-Parsley Mining Company Inc; 1975-06-01 to 1977-03-06; source msha-controller-operator-history
- **operator_operates_mine:** Island Creek Coal Company → No 1; 1977-03-07 to 1979-05-20; source msha-controller-operator-history
- **controller_controls_operator:** Occidental Petroleum Corp → Island Creek Coal Company; 1977-03-07 to 1979-05-20; source msha-controller-operator-history
- **operator_operates_mine:** H & J Coal Company → No 1; 1979-05-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Sanson Herschel → No 1; 1979-05-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sanson Herschel → H & J Coal Company; 1979-05-21 to current/open; source msha-controller-operator-history